Articles | Volume 16, issue 15
https://doi.org/10.5194/acp-16-10083-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-16-10083-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
11 Aug 2016
Research article |
| 11 Aug 2016
Changes in the width of the tropical belt due to simple radiative forcing changes in the GeoMIP simulations
Nicholas A. Davis
CORRESPONDING AUTHOR
Department of Atmospheric Science, Colorado State University, Fort Collins, CO, USA
Dian J. Seidel
NOAA Air Resources Laboratory, College Park, MD, USA
retired
Thomas Birner
Department of Atmospheric Science, Colorado State University, Fort Collins, CO, USA
Sean M. Davis
NOAA Earth System Research Laboratory, Boulder, CO, USA
Simone Tilmes
National Center for Atmospheric Research, Boulder, CO, USA
Related authors
Sean M. Davis, Nicholas Davis, Robert W. Portmann, Eric Ray, and Karen Rosenlof
Atmos. Chem. Phys., 23, 3347–3361, https://doi.org/10.5194/acp-23-3347-2023, https://doi.org/10.5194/acp-23-3347-2023, 2023
Short summary
Short summary
Ozone in the lower part of the stratosphere has not increased and has perhaps even continued to decline in recent decades. This study demonstrates that the amount of ozone in this region is highly sensitive to the amount of air upwelling into the stratosphere in the tropics and that simulations from a climate model nudged to historical meteorological fields often fail to accurately capture the variations in tropical upwelling that control short-term trends in lower-stratospheric ozone.
Nicholas A. Davis, Patrick Callaghan, Isla R. Simpson, and Simone Tilmes
Atmos. Chem. Phys., 22, 197–214, https://doi.org/10.5194/acp-22-197-2022, https://doi.org/10.5194/acp-22-197-2022, 2022
Short summary
Short summary
Specified dynamics schemes attempt to constrain the atmospheric circulation in a climate model to isolate the role of transport in chemical variability, evaluate model physics, and interpret field campaign observations. We show that the specified dynamics scheme in CESM2 erroneously suppresses convection and induces circulation errors that project onto errors in tracers, even using the most optimal settings. Development of a more sophisticated scheme is necessary for future progress.
Nicholas A. Davis, Sean M. Davis, Robert W. Portmann, Eric Ray, Karen H. Rosenlof, and Pengfei Yu
Geosci. Model Dev., 13, 717–734, https://doi.org/10.5194/gmd-13-717-2020, https://doi.org/10.5194/gmd-13-717-2020, 2020
Short summary
Short summary
Large-scale waves drive upward motion in the tropical stratosphere, with major impacts on stratospheric chemistry and climate. However, some of the modeling methods which attempt to simulate the past evolution of the stratosphere do not seem to be able to recreate important trends. We believe this is due to disagreements between the basic climate of the model and observations, but if the method is constructed more carefully, the disagreement becomes smaller and the trends become more realistic.
Zhihong Zhuo, Xinyue Wang, Yunqian Zhu, Ewa M. Bednarz, Eric Fleming, Peter R. Colarco, Shingo Watanabe, David Plummer, Georgiy Stenchikov, William Randel, Adam Bourassa, Valentina Aquila, Takashi Sekiya, Mark R. Schoeberl, Simone Tilmes, Wandi Yu, Jun Zhang, Paul J. Kushner, and Francesco S. R. Pausata
EGUsphere, https://doi.org/10.5194/egusphere-2025-1505, https://doi.org/10.5194/egusphere-2025-1505, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
The 2022 Hunga eruption caused unprecedented stratospheric water injection, triggering unique atmospheric impacts. This study combines observations and model simulations, projecting a stratospheric water vapor anomaly lasting 4–7 years, with significant temperature variations and ozone depletion in the upper atmosphere lasting 7–10 years. These findings offer critical insights into the role of stratospheric water vapor in shaping climate and atmospheric chemistry.
Shenglong Zhang, Jiao Chen, Jonathon S. Wright, Sean M. Davis, Jie Gao, Paul Konopka, Ninghui Li, Mengqian Lu, Susann Tegtmeier, Xiaolu Yan, Guang J. Zhang, and Nuanliang Zhu
EGUsphere, https://doi.org/10.5194/egusphere-2025-543, https://doi.org/10.5194/egusphere-2025-543, 2025
Short summary
Short summary
This study examines water vapor changes in the upper atmosphere above the Asian summer monsoon using satellite data and climate models. Three key patterns of variability were identified: year-to-year changes, and two shifting distributions driven by weather and monsoon dynamics. Despite uncertainties, modern models are improving in capturing these processes. This enhances understanding of water vapor’s role in the upper atmosphere.
Danny M. Leung, Jasper F. Kok, Longlei Li, David M. Lawrence, Natalie M. Mahowald, Simone Tilmes, and Erik Kluzek
Atmos. Chem. Phys., 25, 2311–2331, https://doi.org/10.5194/acp-25-2311-2025, https://doi.org/10.5194/acp-25-2311-2025, 2025
Short summary
Short summary
This study derives a gridded dust emission dataset for 1841–2000 by employing a combination of observed dust from core records and reanalyzed global dust cycle constraints. We evaluate the ability of global models to replicate the observed historical dust variability by using the emission dataset to force a historical simulation in an Earth system model. We show that prescribing our emissions forces the model to better match observations than other mechanistic models.
Jonathon S. Wright, Shenglong Zhang, Jiao Chen, Sean M. Davis, Paul Konopka, Mengqian Lu, Xiaolu Yan, and Guang J. Zhang
EGUsphere, https://doi.org/10.5194/egusphere-2025-135, https://doi.org/10.5194/egusphere-2025-135, 2025
Short summary
Short summary
Atmospheric reanalysis products reconstruct the past states of the atmosphere. These products are often used to study winds and temperatures in the upper-level monsoon circulation, but their ability to reproduce composition fields like water vapor and ozone has been questionable at best. Here we report clear signs of improvement in both consistency across reanalyses and agreement with satellite observations, outline limitations and suggest steps to further enhance the usefulness of these fields.
Mona Zolghadrshojaee, Susann Tegtmeier, Sean M. Davis, Robin Pilch Kedzierski, and Leopold Haimberger
EGUsphere, https://doi.org/10.5194/egusphere-2025-82, https://doi.org/10.5194/egusphere-2025-82, 2025
Short summary
Short summary
The tropical tropopause layer (TTL) is a crucial region where the troposphere transitions into the stratosphere, influencing air mass transport. This study examines temperature trends in the TTL and lower stratosphere using data from weather balloons, satellites, and reanalysis datasets. We found cooling trends in the TTL from 1980–2001, followed by warming from 2002–2023. These shifts are linked to changes in atmospheric circulation and impact water vapor transport into the stratosphere.
Prashant Chavan, Suvarna Fadnavis, Anton Laakso, Jean-Paul Vernier, Simone Tilmes, and Rolf Müller
EGUsphere, https://doi.org/10.5194/egusphere-2024-3825, https://doi.org/10.5194/egusphere-2024-3825, 2025
Short summary
Short summary
Our simulations with volcanoes, when compared without volcanoes, show that volcanic aerosol precursors enter the tropical stratosphere, propagating upward and enhancing sulphate aerosol and heating. This stratospheric heating caused by the volcanoes reduces the amplitude of the QBO and disrupts its phases. Since QBO also modulates tropical convection and weather, we suggest including volcanic emissions and the QBO in the weather prediction model for a better forecast.
Franziska Weyland, Peter Hoor, Daniel Kunkel, Thomas Birner, Felix Plöger, and Katharina Turhal
Atmos. Chem. Phys., 25, 1227–1252, https://doi.org/10.5194/acp-25-1227-2025, https://doi.org/10.5194/acp-25-1227-2025, 2025
Short summary
Short summary
The lowermost stratosphere (LMS) plays an important role in the Earth's climate, containing strong gradients of ozone and water vapor. Our results indicate that the thermodynamic structure of the LMS was changing between 1979–2019 in response to anthropogenic climate change and the recovery of stratospheric ozone, also indicating large-scale circulation changes. We find that both the upper and the lower LMS boundaries show an (upward) trend, which has implications for the LMS mass.
Rasul Baikhadzhaev, Felix Ploeger, Peter Preusse, Manfred Ern, and Thomas Birner
EGUsphere, https://doi.org/10.5194/egusphere-2024-4088, https://doi.org/10.5194/egusphere-2024-4088, 2025
Short summary
Short summary
Across four reanalyses, shallow branch of the stratospheric overturning circulation was found to be driven by the largest waves with wavenumbers 1 to 3, and deep branch of the circulation was found to be driven by smaller-scale waves. Yet, the height of the level separating the branches is depended on the reanalysis considered. Thus using the appropriate separation levels in model inter-comparisons could reduce the spread between models regarding climatology and trends in the circulation.
Katharina Turhal, Felix Plöger, Jan Clemens, Thomas Birner, Franziska Weyland, Paul Konopka, and Peter Hoor
Atmos. Chem. Phys., 24, 13653–13679, https://doi.org/10.5194/acp-24-13653-2024, https://doi.org/10.5194/acp-24-13653-2024, 2024
Short summary
Short summary
The tropopause separates the troposphere, where many greenhouse gases originate, from the stratosphere. This study examines a tropopause defined by potential vorticity – an analogue for angular momentum that changes sharply in the subtropics, creating a transport barrier. Between 1980 and 2017, this tropopause shifted poleward at lower altitudes and equatorward above, suggesting height-dependent changes in atmospheric circulation that may affect greenhouse gas distribution and global warming.
Simone Tilmes, Ewa M. Bednarz, Andrin Jörimann, Daniele Visioni, Douglas E. Kinnison, Gabriel Chiodo, and David Plummer
EGUsphere, https://doi.org/10.5194/egusphere-2024-3586, https://doi.org/10.5194/egusphere-2024-3586, 2024
Short summary
Short summary
This paper describes the details of a new multi-model intercomparison experiment to assess the effects of Stratospheric Aerosol Injections on stratospheric chemistry and dynamics and, therefore, ozone. In this experiment, all models will use the same prescribed stratospheric aerosol distribution and fixed sea-surface temperatures and sea ice. We discuss the advantages and differences of this more constrained experiment compared to previous more interactive model experiments.
Kimberlee Dubé, Susann Tegtmeier, Adam Bourassa, Daniel Zawada, Douglas Degenstein, William Randel, Sean Davis, Michael Schwartz, Nathaniel Livesey, and Anne Smith
Atmos. Chem. Phys., 24, 12925–12941, https://doi.org/10.5194/acp-24-12925-2024, https://doi.org/10.5194/acp-24-12925-2024, 2024
Short summary
Short summary
Greenhouse gas emissions that warm the troposphere also result in stratospheric cooling. The cooling rate is difficult to quantify above 35 km due to a deficit of long-term observational data with high vertical resolution in this region. We use satellite observations from several instruments, including a new temperature product from OSIRIS, to show that the upper stratosphere, from 35–60 km, cooled by 0.5 to 1 K per decade over 2005–2021 and by 0.6 K per decade over 1979–2021.
Yunqian Zhu, Hideharu Akiyoshi, Valentina Aquila, Elisabeth Asher, Ewa M. Bednarz, Slimane Bekki, Christoph Brühl, Amy H. Butler, Parker Case, Simon Chabrillat, Gabriel Chiodo, Margot Clyne, Lola Falletti, Peter R. Colarco, Eric Fleming, Andrin Jörimann, Mahesh Kovilakam, Gerbrand Koren, Ales Kuchar, Nicolas Lebas, Qing Liang, Cheng-Cheng Liu, Graham Mann, Michael Manyin, Marion Marchand, Olaf Morgenstern, Paul Newman, Luke D. Oman, Freja F. Østerstrøm, Yifeng Peng, David Plummer, Ilaria Quaglia, William Randel, Samuel Rémy, Takashi Sekiya, Stephen Steenrod, Timofei Sukhodolov, Simone Tilmes, Kostas Tsigaridis, Rei Ueyama, Daniele Visioni, Xinyue Wang, Shingo Watanabe, Yousuke Yamashita, Pengfei Yu, Wandi Yu, Jun Zhang, and Zhihong Zhuo
EGUsphere, https://doi.org/10.5194/egusphere-2024-3412, https://doi.org/10.5194/egusphere-2024-3412, 2024
Short summary
Short summary
To understand the climate impact of the 2022 Hunga volcanic eruption, we developed a climate model-observation comparison project. The paper describes the protocols and models that participate in the experiments. We designed several experiments to achieve our goal of this activity: 1. evaluate the climate model performance; 2. understand the Earth system responses to this eruption.
Philip Rupp, Jonas Spaeth, Hilla Afargan-Gerstman, Dominik Büeler, Michael Sprenger, and Thomas Birner
Weather Clim. Dynam., 5, 1287–1298, https://doi.org/10.5194/wcd-5-1287-2024, https://doi.org/10.5194/wcd-5-1287-2024, 2024
Short summary
Short summary
We quantify the occurrence of strong synoptic storms as contributing about 20 % to the uncertainty of subseasonal geopotential height forecasts over northern Europe. We further show that North Atlantic storms are less frequent, weaker and shifted southward following sudden stratospheric warming events, leading to a reduction in northern European forecast uncertainty.
Genevieve Rose Lorenzo, Luke D. Ziemba, Avelino F. Arellano, Mary C. Barth, Ewan C. Crosbie, Joshua P. DiGangi, Glenn S. Diskin, Richard Ferrare, Miguel Ricardo A. Hilario, Michael A. Shook, Simone Tilmes, Jian Wang, Qian Xiao, Jun Zhang, and Armin Sorooshian
EGUsphere, https://doi.org/10.5194/egusphere-2024-2604, https://doi.org/10.5194/egusphere-2024-2604, 2024
Short summary
Short summary
Novel aerosol hygroscopicity analysis of CAMP2Ex field campaign data show low aerosol hygroscopicity values in Southeast Asia. Organic carbon from smoke decreases hygroscopicity to levels more like those in continental than in polluted marine regions. Hygroscopicity changes at cloud level demonstrate how surface particles impact clouds in the region affecting model representation of aerosol and cloud interactions in similar polluted marine regions with high organic carbon emissions.
Masatomo Fujiwara, Patrick Martineau, Jonathon S. Wright, Marta Abalos, Petr Šácha, Yoshio Kawatani, Sean M. Davis, Thomas Birner, and Beatriz M. Monge-Sanz
Atmos. Chem. Phys., 24, 7873–7898, https://doi.org/10.5194/acp-24-7873-2024, https://doi.org/10.5194/acp-24-7873-2024, 2024
Short summary
Short summary
A climatology of the major variables and terms of the transformed Eulerian-mean (TEM) momentum and thermodynamic equations from four global atmospheric reanalyses is evaluated. The spread among reanalysis TEM momentum balance terms is around 10 % in Northern Hemisphere winter and up to 50 % in Southern Hemisphere winter. The largest uncertainties in the thermodynamic equation (about 50 %) are in the vertical advection, which does not show a structure consistent with the differences in heating.
Mona Zolghadrshojaee, Susann Tegtmeier, Sean M. Davis, and Robin Pilch Kedzierski
Atmos. Chem. Phys., 24, 7405–7419, https://doi.org/10.5194/acp-24-7405-2024, https://doi.org/10.5194/acp-24-7405-2024, 2024
Short summary
Short summary
Satellite data challenge the idea of an overall cooling trend in the tropical tropopause layer. From 2002 to 2022, a warming trend was observed, diverging from earlier findings. Tropopause height changes indicate dynamic processes alongside radiative effects. Upper-tropospheric warming contrasts with lower-stratosphere temperatures. The study highlights the complex interplay of factors shaping temperature trends.
Christina V. Brodowsky, Timofei Sukhodolov, Gabriel Chiodo, Valentina Aquila, Slimane Bekki, Sandip S. Dhomse, Michael Höpfner, Anton Laakso, Graham W. Mann, Ulrike Niemeier, Giovanni Pitari, Ilaria Quaglia, Eugene Rozanov, Anja Schmidt, Takashi Sekiya, Simone Tilmes, Claudia Timmreck, Sandro Vattioni, Daniele Visioni, Pengfei Yu, Yunqian Zhu, and Thomas Peter
Atmos. Chem. Phys., 24, 5513–5548, https://doi.org/10.5194/acp-24-5513-2024, https://doi.org/10.5194/acp-24-5513-2024, 2024
Short summary
Short summary
The aerosol layer is an essential part of the climate system. We characterize the sulfur budget in a volcanically quiescent (background) setting, with a special focus on the sulfate aerosol layer using, for the first time, a multi-model approach. The aim is to identify weak points in the representation of the atmospheric sulfur budget in an intercomparison of nine state-of-the-art coupled global circulation models.
Anton Laakso, Daniele Visioni, Ulrike Niemeier, Simone Tilmes, and Harri Kokkola
Earth Syst. Dynam., 15, 405–427, https://doi.org/10.5194/esd-15-405-2024, https://doi.org/10.5194/esd-15-405-2024, 2024
Short summary
Short summary
This study is the second in a two-part series in which we explore the dependency of the impacts of stratospheric sulfur injections on both the model employed and the strategy of injection utilized. The study uncovers uncertainties associated with these techniques to cool climate, highlighting how the simulated climate impacts are dependent on both the selected model and the magnitude of the injections. We also show that estimating precipitation impacts of aerosol injection is a complex task.
Daniele Visioni, Alan Robock, Jim Haywood, Matthew Henry, Simone Tilmes, Douglas G. MacMartin, Ben Kravitz, Sarah J. Doherty, John Moore, Chris Lennard, Shingo Watanabe, Helene Muri, Ulrike Niemeier, Olivier Boucher, Abu Syed, Temitope S. Egbebiyi, Roland Séférian, and Ilaria Quaglia
Geosci. Model Dev., 17, 2583–2596, https://doi.org/10.5194/gmd-17-2583-2024, https://doi.org/10.5194/gmd-17-2583-2024, 2024
Short summary
Short summary
This paper describes a new experimental protocol for the Geoengineering Model Intercomparison Project (GeoMIP). In it, we describe the details of a new simulation of sunlight reflection using the stratospheric aerosols that climate models are supposed to run, and we explain the reasons behind each choice we made when defining the protocol.
Danny M. Leung, Jasper F. Kok, Longlei Li, Natalie M. Mahowald, David M. Lawrence, Simone Tilmes, Erik Kluzek, Martina Klose, and Carlos Pérez García-Pando
Atmos. Chem. Phys., 24, 2287–2318, https://doi.org/10.5194/acp-24-2287-2024, https://doi.org/10.5194/acp-24-2287-2024, 2024
Short summary
Short summary
This study uses a premier Earth system model to evaluate a new desert dust emission scheme proposed in our companion paper. We show that our scheme accounts for more dust emission physics, hence matching better against observations than other existing dust emission schemes do. Our scheme's dust emissions also couple tightly with meteorology, hence likely improving the modeled dust sensitivity to climate change. We believe this work is vital for improving dust representation in climate models.
Felix Ploeger, Thomas Birner, Edward Charlesworth, Paul Konopka, and Rolf Müller
Atmos. Chem. Phys., 24, 2033–2043, https://doi.org/10.5194/acp-24-2033-2024, https://doi.org/10.5194/acp-24-2033-2024, 2024
Short summary
Short summary
We present a novel mechanism of how regional anomalies in water vapour concentrations in the upper troposphere and lower stratosphere impact regional atmospheric circulation systems. These impacts include a displaced upper-level Asian monsoon circulation and strengthened prevailing westerlies in the Pacific region. Current climate models have biases in simulating these regional water vapour anomalies and circulation impacts, but the biases can be avoided by improving the model transport.
Abolfazl Rezaei, Khalil Karami, Simone Tilmes, and John C. Moore
Earth Syst. Dynam., 15, 91–108, https://doi.org/10.5194/esd-15-91-2024, https://doi.org/10.5194/esd-15-91-2024, 2024
Short summary
Short summary
Water storage (WS) plays a profound role in the lives of people in the Middle East and North Africa as well as Mediterranean climate "hot spots". WS change by greenhouse gas (GHG) warming is simulated with and without stratospheric aerosol intervention (SAI). WS significantly increases in the Arabian Peninsula and decreases around the Mediterranean under GHG. While SAI partially ameliorates GHG impacts, projected WS increases in dry regions and decreases in wet areas relative to present climate.
Simone Tilmes, Michael J. Mills, Yunqian Zhu, Charles G. Bardeen, Francis Vitt, Pengfei Yu, David Fillmore, Xiaohong Liu, Brian Toon, and Terry Deshler
Geosci. Model Dev., 16, 6087–6125, https://doi.org/10.5194/gmd-16-6087-2023, https://doi.org/10.5194/gmd-16-6087-2023, 2023
Short summary
Short summary
We implemented an alternative aerosol scheme in the high- and low-top model versions of the Community Earth System Model Version 2 (CESM2) with a more detailed description of tropospheric and stratospheric aerosol size distributions than the existing aerosol model. This development enables the comparison of different aerosol schemes with different complexity in the same model framework. It identifies improvements compared to a range of observations in both the troposphere and stratosphere.
Wenfu Tang, Louisa K. Emmons, Helen M. Worden, Rajesh Kumar, Cenlin He, Benjamin Gaubert, Zhonghua Zheng, Simone Tilmes, Rebecca R. Buchholz, Sara-Eva Martinez-Alonso, Claire Granier, Antonin Soulie, Kathryn McKain, Bruce C. Daube, Jeff Peischl, Chelsea Thompson, and Pieternel Levelt
Geosci. Model Dev., 16, 6001–6028, https://doi.org/10.5194/gmd-16-6001-2023, https://doi.org/10.5194/gmd-16-6001-2023, 2023
Short summary
Short summary
The new MUSICAv0 model enables the study of atmospheric chemistry across all relevant scales. We develop a MUSICAv0 grid for Africa. We evaluate MUSICAv0 with observations and compare it with a previously used model – WRF-Chem. Overall, the performance of MUSICAv0 is comparable to WRF-Chem. Based on model–satellite discrepancies, we find that future field campaigns in an eastern African region (30°E–45°E, 5°S–5°N) could substantially improve the predictive skill of air quality models.
Yunqian Zhu, Robert W. Portmann, Douglas Kinnison, Owen Brian Toon, Luis Millán, Jun Zhang, Holger Vömel, Simone Tilmes, Charles G. Bardeen, Xinyue Wang, Stephanie Evan, William J. Randel, and Karen H. Rosenlof
Atmos. Chem. Phys., 23, 13355–13367, https://doi.org/10.5194/acp-23-13355-2023, https://doi.org/10.5194/acp-23-13355-2023, 2023
Short summary
Short summary
The 2022 Hunga Tonga eruption injected a large amount of water into the stratosphere. Ozone depletion was observed inside the volcanic plume. Chlorine and water vapor injected by this eruption exceeded the normal range, which made the ozone chemistry during this event occur at a higher temperature than polar ozone depletion. Unlike polar ozone chemistry where chlorine nitrate is more important, hypochlorous acid plays a large role in the in-plume chlorine balance and heterogeneous processes.
Seyed Vahid Mousavi, Khalil Karami, Simone Tilmes, Helene Muri, Lili Xia, and Abolfazl Rezaei
Atmos. Chem. Phys., 23, 10677–10695, https://doi.org/10.5194/acp-23-10677-2023, https://doi.org/10.5194/acp-23-10677-2023, 2023
Short summary
Short summary
Understanding atmospheric dust changes in the Middle East and North Africa (MENA) region under future climate scenarios is essential. By injecting sulfate aerosols into the stratosphere, stratospheric aerosol injection (SAI) geoengineering reflects some of the incoming sunlight back to space. This study shows that the MENA region would experience lower dust concentration under both SAI and RCP8.5 scenarios compared to the current climate (CTL) by the end of the century.
Frederik Harzer, Hella Garny, Felix Ploeger, Harald Bönisch, Peter Hoor, and Thomas Birner
Atmos. Chem. Phys., 23, 10661–10675, https://doi.org/10.5194/acp-23-10661-2023, https://doi.org/10.5194/acp-23-10661-2023, 2023
Short summary
Short summary
We study the statistical relation between year-by-year fluctuations in winter-mean ozone and the strength of the stratospheric polar vortex. In the latitude–pressure plane, regression analysis shows that anomalously weak polar vortex years are associated with three pronounced local ozone maxima over the polar cap relative to the winter climatology. These response maxima primarily reflect the non-trivial combination of different ozone transport processes with varying relative contributions.
Duseong S. Jo, Simone Tilmes, Louisa K. Emmons, Siyuan Wang, and Francis Vitt
Geosci. Model Dev., 16, 3893–3906, https://doi.org/10.5194/gmd-16-3893-2023, https://doi.org/10.5194/gmd-16-3893-2023, 2023
Short summary
Short summary
A new simple secondary organic aerosol (SOA) scheme has been developed for the Community Atmosphere Model (CAM) based on the complex SOA scheme in CAM with detailed chemistry (CAM-chem). The CAM with the new SOA scheme shows better agreements with CAM-chem in terms of aerosol concentrations and radiative fluxes, which ensures more consistent results between different compsets in the Community Earth System Model. The new SOA scheme also has technical advantages for future developments.
Abolfazl Rezaei, Khalil Karami, Simone Tilmes, and John C. Moore
Atmos. Chem. Phys., 23, 5835–5850, https://doi.org/10.5194/acp-23-5835-2023, https://doi.org/10.5194/acp-23-5835-2023, 2023
Short summary
Short summary
Teleconnection patterns are important characteristics of the climate system; well-known examples include the El Niño and La Niña events driven from the tropical Pacific. We examined how spatiotemporal patterns that arise in the Pacific and Atlantic oceans behave under stratospheric aerosol geoengineering and greenhouse gas (GHG)-induced warming. In general, geoengineering reverses trends; however, the changes in decadal oscillation for the AMO, NAO, and PDO imposed by GHG are not suppressed.
Wenfu Tang, Simone Tilmes, David M. Lawrence, Fang Li, Cenlin He, Louisa K. Emmons, Rebecca R. Buchholz, and Lili Xia
Atmos. Chem. Phys., 23, 5467–5486, https://doi.org/10.5194/acp-23-5467-2023, https://doi.org/10.5194/acp-23-5467-2023, 2023
Short summary
Short summary
Globally, total wildfire burned area is projected to increase over the 21st century under scenarios without geoengineering and decrease under the two geoengineering scenarios. Geoengineering reduces fire by decreasing surface temperature and wind speed and increasing relative humidity and soil water. However, geoengineering also yields reductions in precipitation, which offset some of the fire reduction.
Flossie Brown, Lauren Marshall, Peter H. Haynes, Rolando R. Garcia, Thomas Birner, and Anja Schmidt
Atmos. Chem. Phys., 23, 5335–5353, https://doi.org/10.5194/acp-23-5335-2023, https://doi.org/10.5194/acp-23-5335-2023, 2023
Short summary
Short summary
Large-magnitude volcanic eruptions have the potential to alter large-scale circulation patterns, such as the quasi-biennial oscillation (QBO). The QBO is an oscillation of the tropical stratospheric zonal winds between easterly and westerly directions. Using a climate model, we show that large-magnitude eruptions can delay the progression of the QBO, with a much longer delay when the shear is easterly than when it is westerly. Such delays may affect weather and transport of atmospheric gases.
Daniele Visioni, Ben Kravitz, Alan Robock, Simone Tilmes, Jim Haywood, Olivier Boucher, Mark Lawrence, Peter Irvine, Ulrike Niemeier, Lili Xia, Gabriel Chiodo, Chris Lennard, Shingo Watanabe, John C. Moore, and Helene Muri
Atmos. Chem. Phys., 23, 5149–5176, https://doi.org/10.5194/acp-23-5149-2023, https://doi.org/10.5194/acp-23-5149-2023, 2023
Short summary
Short summary
Geoengineering indicates methods aiming to reduce the temperature of the planet by means of reflecting back a part of the incoming radiation before it reaches the surface or allowing more of the planetary radiation to escape into space. It aims to produce modelling experiments that are easy to reproduce and compare with different climate models, in order to understand the potential impacts of these techniques. Here we assess its past successes and failures and talk about its future.
Khalil Karami, Rolando Garcia, Christoph Jacobi, Jadwiga H. Richter, and Simone Tilmes
Atmos. Chem. Phys., 23, 3799–3818, https://doi.org/10.5194/acp-23-3799-2023, https://doi.org/10.5194/acp-23-3799-2023, 2023
Short summary
Short summary
Alongside mitigation and adaptation efforts, stratospheric aerosol intervention (SAI) is increasingly considered a third pillar to combat dangerous climate change. We investigate the teleconnection between the quasi-biennial oscillation in the equatorial stratosphere and the Arctic stratospheric polar vortex under a warmer climate and an SAI scenario. We show that the Holton–Tan relationship weakens under both scenarios and discuss the physical mechanisms responsible for such changes.
Sean M. Davis, Nicholas Davis, Robert W. Portmann, Eric Ray, and Karen Rosenlof
Atmos. Chem. Phys., 23, 3347–3361, https://doi.org/10.5194/acp-23-3347-2023, https://doi.org/10.5194/acp-23-3347-2023, 2023
Short summary
Short summary
Ozone in the lower part of the stratosphere has not increased and has perhaps even continued to decline in recent decades. This study demonstrates that the amount of ozone in this region is highly sensitive to the amount of air upwelling into the stratosphere in the tropics and that simulations from a climate model nudged to historical meteorological fields often fail to accurately capture the variations in tropical upwelling that control short-term trends in lower-stratospheric ozone.
J. Douglas Goetz, Lars E. Kalnajs, Terry Deshler, Sean M. Davis, Martina Bramberger, and M. Joan Alexander
Atmos. Meas. Tech., 16, 791–807, https://doi.org/10.5194/amt-16-791-2023, https://doi.org/10.5194/amt-16-791-2023, 2023
Short summary
Short summary
An instrument for in situ continuous 2 km vertical profiles of temperature below high-altitude balloons was developed for high-temporal-resolution measurements within the upper troposphere and lower stratosphere using fiber-optic distributed temperature sensing. The mechanical, electrical, and temperature calibration systems were validated from a short mid-latitude constant-altitude balloon flight within the lower stratosphere. The instrument observed small-scale and inertial gravity waves.
Yangxin Chen, Duoying Ji, Qian Zhang, John C. Moore, Olivier Boucher, Andy Jones, Thibaut Lurton, Michael J. Mills, Ulrike Niemeier, Roland Séférian, and Simone Tilmes
Earth Syst. Dynam., 14, 55–79, https://doi.org/10.5194/esd-14-55-2023, https://doi.org/10.5194/esd-14-55-2023, 2023
Short summary
Short summary
Solar geoengineering has been proposed as a way of counteracting the warming effects of increasing greenhouse gases by reflecting solar radiation. This work shows that solar geoengineering can slow down the northern-high-latitude permafrost degradation but cannot preserve the permafrost ecosystem as that under a climate of the same warming level without solar geoengineering.
Felix Jäger, Philip Rupp, and Thomas Birner
Weather Clim. Dynam., 4, 49–60, https://doi.org/10.5194/wcd-4-49-2023, https://doi.org/10.5194/wcd-4-49-2023, 2023
Short summary
Short summary
Mid-latitude weather is dominated by the growth, breaking and decay of baroclinic waves and associated jet shifts. A way to study this process is via idealised life-cycle simulations, which are often classified as LC1 (anticyclonic breaking, poleward shift) or LC2 (cyclonic breaking, equatorward shift), depending on details of the initial state. We show that all systems exhibit predominantly anticyclonic character and poleward net shifts if multiple wave modes are allowed to grow simultaneously.
Sophie Godin-Beekmann, Niramson Azouz, Viktoria F. Sofieva, Daan Hubert, Irina Petropavlovskikh, Peter Effertz, Gérard Ancellet, Doug A. Degenstein, Daniel Zawada, Lucien Froidevaux, Stacey Frith, Jeannette Wild, Sean Davis, Wolfgang Steinbrecht, Thierry Leblanc, Richard Querel, Kleareti Tourpali, Robert Damadeo, Eliane Maillard Barras, René Stübi, Corinne Vigouroux, Carlo Arosio, Gerald Nedoluha, Ian Boyd, Roeland Van Malderen, Emmanuel Mahieu, Dan Smale, and Ralf Sussmann
Atmos. Chem. Phys., 22, 11657–11673, https://doi.org/10.5194/acp-22-11657-2022, https://doi.org/10.5194/acp-22-11657-2022, 2022
Short summary
Short summary
An updated evaluation up to 2020 of stratospheric ozone profile long-term trends at extrapolar latitudes based on satellite and ground-based records is presented. Ozone increase in the upper stratosphere is confirmed, with significant trends at most latitudes. In this altitude region, a very good agreement is found with trends derived from chemistry–climate model simulations. Observed and modelled trends diverge in the lower stratosphere, but the differences are non-significant.
Mari R. Tye, Katherine Dagon, Maria J. Molina, Jadwiga H. Richter, Daniele Visioni, Ben Kravitz, and Simone Tilmes
Earth Syst. Dynam., 13, 1233–1257, https://doi.org/10.5194/esd-13-1233-2022, https://doi.org/10.5194/esd-13-1233-2022, 2022
Short summary
Short summary
We examined the potential effect of stratospheric aerosol injection (SAI) on extreme temperature and precipitation. SAI may cause daytime temperatures to cool but nighttime to warm. Daytime cooling may occur in all seasons across the globe, with the largest decreases in summer. In contrast, nighttime warming may be greatest at high latitudes in winter. SAI may reduce the frequency and intensity of extreme rainfall. The combined changes may exacerbate drying over parts of the global south.
Jonas Spaeth and Thomas Birner
Weather Clim. Dynam., 3, 883–903, https://doi.org/10.5194/wcd-3-883-2022, https://doi.org/10.5194/wcd-3-883-2022, 2022
Short summary
Short summary
Past research has demonstrated robust stratosphere–troposphere dynamical coupling following stratospheric circulation extremes. Here, we use a large set of extended-range ensemble forecasts to robustly quantify the increased risk for tropospheric circulation extremes following stratospheric extreme events. In particular, we provide estimates of the fraction of tropospheric extremes that may be attributable to preceding stratospheric extremes.
Shlomi Ziskin Ziv, Chaim I. Garfinkel, Sean Davis, and Antara Banerjee
Atmos. Chem. Phys., 22, 7523–7538, https://doi.org/10.5194/acp-22-7523-2022, https://doi.org/10.5194/acp-22-7523-2022, 2022
Short summary
Short summary
Stratospheric water vapor is important for Earth's overall greenhouse effect and for ozone chemistry; however the factors governing its variability on interannual timescales are not fully known, and previous modeling studies have indicated that models struggle to capture this interannual variability. We demonstrate that nonlinear interactions are important for determining overall water vapor concentrations and also that models have improved in their ability to capture these connections.
Simone Tilmes, Daniele Visioni, Andy Jones, James Haywood, Roland Séférian, Pierre Nabat, Olivier Boucher, Ewa Monica Bednarz, and Ulrike Niemeier
Atmos. Chem. Phys., 22, 4557–4579, https://doi.org/10.5194/acp-22-4557-2022, https://doi.org/10.5194/acp-22-4557-2022, 2022
Short summary
Short summary
This study assesses the impacts of climate interventions, using stratospheric sulfate aerosol and solar dimming on stratospheric ozone, based on three Earth system models with interactive stratospheric chemistry. The climate interventions have been applied to a high emission (baseline) scenario in order to reach global surface temperatures of a medium emission scenario. We find significant increases and decreases in total column ozone, depending on regions and seasons.
Andy Jones, Jim M. Haywood, Adam A. Scaife, Olivier Boucher, Matthew Henry, Ben Kravitz, Thibaut Lurton, Pierre Nabat, Ulrike Niemeier, Roland Séférian, Simone Tilmes, and Daniele Visioni
Atmos. Chem. Phys., 22, 2999–3016, https://doi.org/10.5194/acp-22-2999-2022, https://doi.org/10.5194/acp-22-2999-2022, 2022
Short summary
Short summary
Simulations by six Earth-system models of geoengineering by introducing sulfuric acid aerosols into the tropical stratosphere are compared. A robust impact on the northern wintertime North Atlantic Oscillation is found, exacerbating precipitation reduction over parts of southern Europe. In contrast, the models show no consistency with regard to impacts on the Quasi-Biennial Oscillation, although results do indicate a risk that the oscillation could become locked into a permanent westerly phase.
Daniele Visioni, Simone Tilmes, Charles Bardeen, Michael Mills, Douglas G. MacMartin, Ben Kravitz, and Jadwiga H. Richter
Atmos. Chem. Phys., 22, 1739–1756, https://doi.org/10.5194/acp-22-1739-2022, https://doi.org/10.5194/acp-22-1739-2022, 2022
Short summary
Short summary
Aerosols are simulated in a simplified way in climate models: in the model analyzed here, they are represented in every grid as described by three simple logarithmic distributions, mixing all different species together. The size can evolve when new particles are formed, particles merge together to create a larger one or particles are deposited to the surface. This approximation normally works fairly well. Here we show however that when large amounts of sulfate are simulated, there are problems.
Nicholas A. Davis, Patrick Callaghan, Isla R. Simpson, and Simone Tilmes
Atmos. Chem. Phys., 22, 197–214, https://doi.org/10.5194/acp-22-197-2022, https://doi.org/10.5194/acp-22-197-2022, 2022
Short summary
Short summary
Specified dynamics schemes attempt to constrain the atmospheric circulation in a climate model to isolate the role of transport in chemical variability, evaluate model physics, and interpret field campaign observations. We show that the specified dynamics scheme in CESM2 erroneously suppresses convection and induces circulation errors that project onto errors in tracers, even using the most optimal settings. Development of a more sophisticated scheme is necessary for future progress.
Anton Laakso, Ulrike Niemeier, Daniele Visioni, Simone Tilmes, and Harri Kokkola
Atmos. Chem. Phys., 22, 93–118, https://doi.org/10.5194/acp-22-93-2022, https://doi.org/10.5194/acp-22-93-2022, 2022
Short summary
Short summary
The use of different spatio-temporal sulfur injection strategies with different magnitudes to create an artificial reflective aerosol layer to cool the climate is studied using sectional and modal aerosol schemes in a climate model. There are significant differences in the results depending on the aerosol microphysical module used. Different spatio-temporal injection strategies have a significant impact on the magnitude and zonal distribution of radiative forcing and atmospheric dynamics.
Thierno Doumbia, Claire Granier, Nellie Elguindi, Idir Bouarar, Sabine Darras, Guy Brasseur, Benjamin Gaubert, Yiming Liu, Xiaoqin Shi, Trissevgeni Stavrakou, Simone Tilmes, Forrest Lacey, Adrien Deroubaix, and Tao Wang
Earth Syst. Sci. Data, 13, 4191–4206, https://doi.org/10.5194/essd-13-4191-2021, https://doi.org/10.5194/essd-13-4191-2021, 2021
Short summary
Short summary
Most countries around the world have implemented control measures to combat the spread of the COVID-19 pandemic, resulting in significant changes in economic and personal activities. We developed the CONFORM (COvid-19 adjustmeNt Factors fOR eMissions) dataset to account for changes in emissions during lockdowns. This dataset was created with the intention of being directly applicable to existing global and regional inventories used in chemical transport models.
Daniele Visioni, Douglas G. MacMartin, Ben Kravitz, Olivier Boucher, Andy Jones, Thibaut Lurton, Michou Martine, Michael J. Mills, Pierre Nabat, Ulrike Niemeier, Roland Séférian, and Simone Tilmes
Atmos. Chem. Phys., 21, 10039–10063, https://doi.org/10.5194/acp-21-10039-2021, https://doi.org/10.5194/acp-21-10039-2021, 2021
Short summary
Short summary
A new set of simulations is used to investigate commonalities, differences and sources of uncertainty when simulating the injection of SO2 in the stratosphere in order to mitigate the effects of climate change (solar geoengineering). The models differ in how they simulate the aerosols and how they spread around the stratosphere, resulting in differences in projected regional impacts. Overall, however, the models agree that aerosols have the potential to mitigate the warming produced by GHGs.
Fernando Chouza, Thierry Leblanc, Mark Brewer, Patrick Wang, Sabino Piazzolla, Gabriele Pfister, Rajesh Kumar, Carl Drews, Simone Tilmes, Louisa Emmons, and Matthew Johnson
Atmos. Chem. Phys., 21, 6129–6153, https://doi.org/10.5194/acp-21-6129-2021, https://doi.org/10.5194/acp-21-6129-2021, 2021
Short summary
Short summary
The tropospheric ozone lidar at the JPL Table Mountain Facility (TMF) was used to investigate the impact of Los Angeles (LA) Basin pollution transport and stratospheric intrusions in the planetary boundary layer on the San Gabriel Mountains. The results of this study indicate a dominant role of the LA Basin pollution on days when high ozone levels were observed at TMF (March–October period).
Lars E. Kalnajs, Sean M. Davis, J. Douglas Goetz, Terry Deshler, Sergey Khaykin, Alex St. Clair, Albert Hertzog, Jerome Bordereau, and Alexey Lykov
Atmos. Meas. Tech., 14, 2635–2648, https://doi.org/10.5194/amt-14-2635-2021, https://doi.org/10.5194/amt-14-2635-2021, 2021
Short summary
Short summary
This work introduces a novel instrument system for high-resolution atmospheric profiling, which lowers and retracts a suspended instrument package beneath drifting long-duration balloons. During a 100 d circumtropical flight, the instrument collected over a hundred 2 km profiles of temperature, water vapor, clouds, and aerosol at 1 m resolution, yielding unprecedented geographic sampling and vertical resolution measurements of the tropical tropopause layer.
James Keeble, Birgit Hassler, Antara Banerjee, Ramiro Checa-Garcia, Gabriel Chiodo, Sean Davis, Veronika Eyring, Paul T. Griffiths, Olaf Morgenstern, Peer Nowack, Guang Zeng, Jiankai Zhang, Greg Bodeker, Susannah Burrows, Philip Cameron-Smith, David Cugnet, Christopher Danek, Makoto Deushi, Larry W. Horowitz, Anne Kubin, Lijuan Li, Gerrit Lohmann, Martine Michou, Michael J. Mills, Pierre Nabat, Dirk Olivié, Sungsu Park, Øyvind Seland, Jens Stoll, Karl-Hermann Wieners, and Tongwen Wu
Atmos. Chem. Phys., 21, 5015–5061, https://doi.org/10.5194/acp-21-5015-2021, https://doi.org/10.5194/acp-21-5015-2021, 2021
Short summary
Short summary
Stratospheric ozone and water vapour are key components of the Earth system; changes to both have important impacts on global and regional climate. We evaluate changes to these species from 1850 to 2100 in the new generation of CMIP6 models. There is good agreement between the multi-model mean and observations, although there is substantial variation between the individual models. The future evolution of both ozone and water vapour is strongly dependent on the assumed future emissions scenario.
Ben Kravitz, Douglas G. MacMartin, Daniele Visioni, Olivier Boucher, Jason N. S. Cole, Jim Haywood, Andy Jones, Thibaut Lurton, Pierre Nabat, Ulrike Niemeier, Alan Robock, Roland Séférian, and Simone Tilmes
Atmos. Chem. Phys., 21, 4231–4247, https://doi.org/10.5194/acp-21-4231-2021, https://doi.org/10.5194/acp-21-4231-2021, 2021
Short summary
Short summary
This study investigates multi-model response to idealized geoengineering (high CO2 with solar reduction) across two different generations of climate models. We find that, with the exception of a few cases, the results are unchanged between the different generations. This gives us confidence that broad conclusions about the response to idealized geoengineering are robust.
Paul T. Griffiths, Lee T. Murray, Guang Zeng, Youngsub Matthew Shin, N. Luke Abraham, Alexander T. Archibald, Makoto Deushi, Louisa K. Emmons, Ian E. Galbally, Birgit Hassler, Larry W. Horowitz, James Keeble, Jane Liu, Omid Moeini, Vaishali Naik, Fiona M. O'Connor, Naga Oshima, David Tarasick, Simone Tilmes, Steven T. Turnock, Oliver Wild, Paul J. Young, and Prodromos Zanis
Atmos. Chem. Phys., 21, 4187–4218, https://doi.org/10.5194/acp-21-4187-2021, https://doi.org/10.5194/acp-21-4187-2021, 2021
Short summary
Short summary
We analyse the CMIP6 Historical and future simulations for tropospheric ozone, a species which is important for many aspects of atmospheric chemistry. We show that the current generation of models agrees well with observations, being particularly successful in capturing trends in surface ozone and its vertical distribution in the troposphere. We analyse the factors that control ozone and show that they evolve over the period of the CMIP6 experiments.
Chaim I. Garfinkel, Ohad Harari, Shlomi Ziskin Ziv, Jian Rao, Olaf Morgenstern, Guang Zeng, Simone Tilmes, Douglas Kinnison, Fiona M. O'Connor, Neal Butchart, Makoto Deushi, Patrick Jöckel, Andrea Pozzer, and Sean Davis
Atmos. Chem. Phys., 21, 3725–3740, https://doi.org/10.5194/acp-21-3725-2021, https://doi.org/10.5194/acp-21-3725-2021, 2021
Short summary
Short summary
Water vapor is the dominant greenhouse gas in the atmosphere, and El Niño is the dominant mode of variability in the ocean–atmosphere system. The connection between El Niño and water vapor above ~ 17 km is unclear, with single-model studies reaching a range of conclusions. This study examines this connection in 12 different models. While there are substantial differences among the models, all models appear to capture the fundamental physical processes correctly.
Duseong S. Jo, Alma Hodzic, Louisa K. Emmons, Simone Tilmes, Rebecca H. Schwantes, Michael J. Mills, Pedro Campuzano-Jost, Weiwei Hu, Rahul A. Zaveri, Richard C. Easter, Balwinder Singh, Zheng Lu, Christiane Schulz, Johannes Schneider, John E. Shilling, Armin Wisthaler, and Jose L. Jimenez
Atmos. Chem. Phys., 21, 3395–3425, https://doi.org/10.5194/acp-21-3395-2021, https://doi.org/10.5194/acp-21-3395-2021, 2021
Short summary
Short summary
Secondary organic aerosol (SOA) is a major component of submicron particulate matter, but there are a lot of uncertainties in the future prediction of SOA. We used CESM 2.1 to investigate future IEPOX SOA concentration changes. The explicit chemistry predicted substantial changes in IEPOX SOA depending on the future scenario, but the parameterization predicted weak changes due to simplified chemistry, which shows the importance of correct physicochemical dependencies in future SOA prediction.
Sabine Robrecht, Bärbel Vogel, Simone Tilmes, and Rolf Müller
Atmos. Chem. Phys., 21, 2427–2455, https://doi.org/10.5194/acp-21-2427-2021, https://doi.org/10.5194/acp-21-2427-2021, 2021
Short summary
Short summary
Column ozone protects life on Earth from radiation damage. Stratospheric chlorine compounds cause immense ozone loss in polar winter. Whether similar loss processes can occur in the lower stratosphere above North America today or in future is a matter of debate. We show that these ozone loss processes are very unlikely today or in future independently of whether sulfate geoengineering is applied and that less than 0.1 % of column ozone would be destroyed by this process in any future scenario.
Philip Rupp and Thomas Birner
Weather Clim. Dynam., 2, 111–128, https://doi.org/10.5194/wcd-2-111-2021, https://doi.org/10.5194/wcd-2-111-2021, 2021
Short summary
Short summary
We use the simple framework of an idealised baroclinic life cycle to study the tropospheric eddy feedback to different stratospheric conditions and, hence, obtain insights into the fundamental processes of stratosphere–troposphere coupling – in particular, the processes involved in creating the robust equatorward shift in the tropospheric mid-latitude jet that has been observed following sudden stratospheric warming events.
Andy Jones, Jim M. Haywood, Anthony C. Jones, Simone Tilmes, Ben Kravitz, and Alan Robock
Atmos. Chem. Phys., 21, 1287–1304, https://doi.org/10.5194/acp-21-1287-2021, https://doi.org/10.5194/acp-21-1287-2021, 2021
Short summary
Short summary
Two different methods of simulating a geoengineering scenario are compared using data from two different Earth system models. One method is very idealised while the other includes details of a plausible mechanism. The results from both models agree that the idealised approach does not capture an impact found when detailed modelling is included, namely that geoengineering induces a positive phase of the North Atlantic Oscillation which leads to warmer, wetter winters in northern Europe.
Marc von Hobe, Felix Ploeger, Paul Konopka, Corinna Kloss, Alexey Ulanowski, Vladimir Yushkov, Fabrizio Ravegnani, C. Michael Volk, Laura L. Pan, Shawn B. Honomichl, Simone Tilmes, Douglas E. Kinnison, Rolando R. Garcia, and Jonathon S. Wright
Atmos. Chem. Phys., 21, 1267–1285, https://doi.org/10.5194/acp-21-1267-2021, https://doi.org/10.5194/acp-21-1267-2021, 2021
Short summary
Short summary
The Asian summer monsoon (ASM) is known to foster transport of polluted tropospheric air into the stratosphere. To test and amend our picture of ASM vertical transport, we analyse distributions of airborne trace gas observations up to 20 km altitude near the main ASM vertical conduit south of the Himalayas. We also show that a new high-resolution version of the global chemistry climate model WACCM is able to reproduce the observations well.
Gillian Thornhill, William Collins, Dirk Olivié, Ragnhild B. Skeie, Alex Archibald, Susanne Bauer, Ramiro Checa-Garcia, Stephanie Fiedler, Gerd Folberth, Ada Gjermundsen, Larry Horowitz, Jean-Francois Lamarque, Martine Michou, Jane Mulcahy, Pierre Nabat, Vaishali Naik, Fiona M. O'Connor, Fabien Paulot, Michael Schulz, Catherine E. Scott, Roland Séférian, Chris Smith, Toshihiko Takemura, Simone Tilmes, Kostas Tsigaridis, and James Weber
Atmos. Chem. Phys., 21, 1105–1126, https://doi.org/10.5194/acp-21-1105-2021, https://doi.org/10.5194/acp-21-1105-2021, 2021
Short summary
Short summary
We find that increased temperatures affect aerosols and reactive gases by changing natural emissions and their rates of removal from the atmosphere. Changing the composition of these species in the atmosphere affects the radiative budget of the climate system and therefore amplifies or dampens the climate response of climate models of the Earth system. This study found that the largest effect is a dampening of climate change as warmer temperatures increase the emissions of cooling aerosols.
Gillian D. Thornhill, William J. Collins, Ryan J. Kramer, Dirk Olivié, Ragnhild B. Skeie, Fiona M. O'Connor, Nathan Luke Abraham, Ramiro Checa-Garcia, Susanne E. Bauer, Makoto Deushi, Louisa K. Emmons, Piers M. Forster, Larry W. Horowitz, Ben Johnson, James Keeble, Jean-Francois Lamarque, Martine Michou, Michael J. Mills, Jane P. Mulcahy, Gunnar Myhre, Pierre Nabat, Vaishali Naik, Naga Oshima, Michael Schulz, Christopher J. Smith, Toshihiko Takemura, Simone Tilmes, Tongwen Wu, Guang Zeng, and Jie Zhang
Atmos. Chem. Phys., 21, 853–874, https://doi.org/10.5194/acp-21-853-2021, https://doi.org/10.5194/acp-21-853-2021, 2021
Short summary
Short summary
This paper is a study of how different constituents in the atmosphere, such as aerosols and gases like methane and ozone, affect the energy balance in the atmosphere. Different climate models were run using the same inputs to allow an easy comparison of the results and to understand where the models differ. We found the effect of aerosols is to reduce warming in the atmosphere, but this effect varies between models. Reactions between gases are also important in affecting climate.
Benjamin Gaubert, Louisa K. Emmons, Kevin Raeder, Simone Tilmes, Kazuyuki Miyazaki, Avelino F. Arellano Jr., Nellie Elguindi, Claire Granier, Wenfu Tang, Jérôme Barré, Helen M. Worden, Rebecca R. Buchholz, David P. Edwards, Philipp Franke, Jeffrey L. Anderson, Marielle Saunois, Jason Schroeder, Jung-Hun Woo, Isobel J. Simpson, Donald R. Blake, Simone Meinardi, Paul O. Wennberg, John Crounse, Alex Teng, Michelle Kim, Russell R. Dickerson, Hao He, Xinrong Ren, Sally E. Pusede, and Glenn S. Diskin
Atmos. Chem. Phys., 20, 14617–14647, https://doi.org/10.5194/acp-20-14617-2020, https://doi.org/10.5194/acp-20-14617-2020, 2020
Short summary
Short summary
This study investigates carbon monoxide pollution in East Asia during spring using a numerical model, satellite remote sensing, and aircraft measurements. We found an underestimation of emission sources. Correcting the emission bias can improve air quality forecasting of carbon monoxide and other species including ozone. Results also suggest that controlling VOC and CO emissions, in addition to widespread NOx controls, can improve ozone pollution over East Asia.
Steven T. Turnock, Robert J. Allen, Martin Andrews, Susanne E. Bauer, Makoto Deushi, Louisa Emmons, Peter Good, Larry Horowitz, Jasmin G. John, Martine Michou, Pierre Nabat, Vaishali Naik, David Neubauer, Fiona M. O'Connor, Dirk Olivié, Naga Oshima, Michael Schulz, Alistair Sellar, Sungbo Shim, Toshihiko Takemura, Simone Tilmes, Kostas Tsigaridis, Tongwen Wu, and Jie Zhang
Atmos. Chem. Phys., 20, 14547–14579, https://doi.org/10.5194/acp-20-14547-2020, https://doi.org/10.5194/acp-20-14547-2020, 2020
Short summary
Short summary
A first assessment is made of the historical and future changes in air pollutants from models participating in the 6th Coupled Model Intercomparison Project (CMIP6). Substantial benefits to future air quality can be achieved in future scenarios that implement measures to mitigate climate and involve reductions in air pollutant emissions, particularly methane. However, important differences are shown between models in the future regional projection of air pollutants under the same scenario.
Augustin Mortier, Jonas Gliß, Michael Schulz, Wenche Aas, Elisabeth Andrews, Huisheng Bian, Mian Chin, Paul Ginoux, Jenny Hand, Brent Holben, Hua Zhang, Zak Kipling, Alf Kirkevåg, Paolo Laj, Thibault Lurton, Gunnar Myhre, David Neubauer, Dirk Olivié, Knut von Salzen, Ragnhild Bieltvedt Skeie, Toshihiko Takemura, and Simone Tilmes
Atmos. Chem. Phys., 20, 13355–13378, https://doi.org/10.5194/acp-20-13355-2020, https://doi.org/10.5194/acp-20-13355-2020, 2020
Short summary
Short summary
We present a multiparameter analysis of the aerosol trends over the last 2 decades in the different regions of the world. In most of the regions, ground-based observations show a decrease in aerosol content in both the total atmospheric column and at the surface. The use of climate models, assessed against these observations, reveals however an increase in the total aerosol load, which is not seen with the sole use of observation due to partial coverage in space and time.
Yuanhong Zhao, Marielle Saunois, Philippe Bousquet, Xin Lin, Antoine Berchet, Michaela I. Hegglin, Josep G. Canadell, Robert B. Jackson, Makoto Deushi, Patrick Jöckel, Douglas Kinnison, Ole Kirner, Sarah Strode, Simone Tilmes, Edward J. Dlugokencky, and Bo Zheng
Atmos. Chem. Phys., 20, 13011–13022, https://doi.org/10.5194/acp-20-13011-2020, https://doi.org/10.5194/acp-20-13011-2020, 2020
Short summary
Short summary
Decadal trends and variations in OH are critical for understanding atmospheric CH4 evolution. We quantify the impacts of OH trends and variations on the CH4 budget by conducting CH4 inversions on a decadal scale with an ensemble of OH fields. We find the negative OH anomalies due to enhanced fires can reduce the optimized CH4 emissions by up to 10 Tg yr−1 during El Niño years and the positive OH trend from 1986 to 2010 results in a ∼ 23 Tg yr−1 additional increase in optimized CH4 emissions.
David S. Stevenson, Alcide Zhao, Vaishali Naik, Fiona M. O'Connor, Simone Tilmes, Guang Zeng, Lee T. Murray, William J. Collins, Paul T. Griffiths, Sungbo Shim, Larry W. Horowitz, Lori T. Sentman, and Louisa Emmons
Atmos. Chem. Phys., 20, 12905–12920, https://doi.org/10.5194/acp-20-12905-2020, https://doi.org/10.5194/acp-20-12905-2020, 2020
Short summary
Short summary
We present historical trends in atmospheric oxidizing capacity (OC) since 1850 from the latest generation of global climate models and compare these with estimates from measurements. OC controls levels of many key reactive gases, including methane (CH4). We find small model trends up to 1980, then increases of about 9 % up to 2014, disagreeing with (uncertain) measurement-based trends. Major drivers of OC trends are emissions of CH4, NOx, and CO; these will be important for future CH4 trends.
Hella Garny, Roland Walz, Matthias Nützel, and Thomas Birner
Geosci. Model Dev., 13, 5229–5257, https://doi.org/10.5194/gmd-13-5229-2020, https://doi.org/10.5194/gmd-13-5229-2020, 2020
Short summary
Short summary
Numerical models of Earth's climate system have been gaining more and more complexity over the last decades. Therefore, it is important to establish simplified models to improve process understanding. In our study, we present and document the development of a new simplified model setup within the framework of a complex climate model system that uses the same routines to calculate atmospheric dynamics as the complex model but is simplified in the representation of clouds and radiation.
Lina Boljka and Thomas Birner
Weather Clim. Dynam., 1, 555–575, https://doi.org/10.5194/wcd-1-555-2020, https://doi.org/10.5194/wcd-1-555-2020, 2020
Short summary
Short summary
This study addresses the origin and impacts of a source of large-scale atmospheric waves in the lower stratosphere, which have not been examined before. This wave source is caused by interactions of waves of smaller scales. Here we show that as it lies in the lower stratosphere, this wave source can precede extreme events in the stratosphere and that such events can then lead to a response of the tropospheric weather patterns several weeks later (potential for long-term forecasting).
Stephanie Evan, Jerome Brioude, Karen Rosenlof, Sean M. Davis, Holger Vömel, Damien Héron, Françoise Posny, Jean-Marc Metzger, Valentin Duflot, Guillaume Payen, Hélène Vérèmes, Philippe Keckhut, and Jean-Pierre Cammas
Atmos. Chem. Phys., 20, 10565–10586, https://doi.org/10.5194/acp-20-10565-2020, https://doi.org/10.5194/acp-20-10565-2020, 2020
Short summary
Short summary
The role of deep convection in the southwest Indian Ocean (the 3rd most active tropical cyclone basin) on the composition of the tropical tropopause layer (TTL) and the climate system is less understood due to scarce observations. Balloon-borne lidar and satellite measurements in the southwest Indian Ocean were used to study tropical cyclones' influence on TTL composition. This study compares the impact of a tropical storm and cyclone on the humidification of the TTL over the SW Indian Ocean.
Wenfu Tang, Benjamin Gaubert, Louisa Emmons, Yonghoon Choi, Joshua P. DiGangi, Glenn S. Diskin, Xiaomei Xu, Cenlin He, Helen Worden, Simone Tilmes, Rebecca Buchholz, Hannah S. Halliday, and Avelino F. Arellano
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-864, https://doi.org/10.5194/acp-2020-864, 2020
Revised manuscript not accepted
Short summary
Short summary
A specific demonstration of the potential use of correlative information from carbon monoxide to refine estimates of regional carbon dioxide emissions from fossil fuel combustion.
Matt Amos, Paul J. Young, J. Scott Hosking, Jean-François Lamarque, N. Luke Abraham, Hideharu Akiyoshi, Alexander T. Archibald, Slimane Bekki, Makoto Deushi, Patrick Jöckel, Douglas Kinnison, Ole Kirner, Markus Kunze, Marion Marchand, David A. Plummer, David Saint-Martin, Kengo Sudo, Simone Tilmes, and Yousuke Yamashita
Atmos. Chem. Phys., 20, 9961–9977, https://doi.org/10.5194/acp-20-9961-2020, https://doi.org/10.5194/acp-20-9961-2020, 2020
Short summary
Short summary
We present an updated projection of Antarctic ozone hole recovery using an ensemble of chemistry–climate models. To do so, we employ a method, more advanced and skilful than the current multi-model mean standard, which is applicable to other ensemble analyses. It calculates the performance and similarity of the models, which we then use to weight the model. Calculating model similarity allows us to account for models which are constructed from similar components.
Yangyang Xu, Lei Lin, Simone Tilmes, Katherine Dagon, Lili Xia, Chenrui Diao, Wei Cheng, Zhili Wang, Isla Simpson, and Lorna Burnell
Earth Syst. Dynam., 11, 673–695, https://doi.org/10.5194/esd-11-673-2020, https://doi.org/10.5194/esd-11-673-2020, 2020
Short summary
Short summary
Two geoengineering schemes to mitigate global warming, (a) capturing atmospheric CO2 and (b) injecting stratospheric sulfur gas, are compared. Based on two sets of large-ensemble model experiments, we show that sulfur injection will effectively mitigate projected terrestrial drying over the Americas, and the mitigation benefit will emerge more quickly than with carbon capture. Innovative means of sulfur injection should continue to be explored as one potential low-cost climate solution.
Ulrike Niemeier, Jadwiga H. Richter, and Simone Tilmes
Atmos. Chem. Phys., 20, 8975–8987, https://doi.org/10.5194/acp-20-8975-2020, https://doi.org/10.5194/acp-20-8975-2020, 2020
Short summary
Short summary
Artificial injections of SO2 into the tropical stratosphere show an impact on the quasi-biennial oscillation (QBO). Different numerical models show only qualitatively but not quantitatively consistent impacts. We show for two models that the response of the QBO is similar when a similar stratospheric heating rate is induced by SO2 injections of different amounts. The reason is very different vertical advection in the two models resulting in different aerosol burden and heating of the aerosols.
Simone Tilmes, Douglas G. MacMartin, Jan T. M. Lenaerts, Leo van Kampenhout, Laura Muntjewerf, Lili Xia, Cheryl S. Harrison, Kristen M. Krumhardt, Michael J. Mills, Ben Kravitz, and Alan Robock
Earth Syst. Dynam., 11, 579–601, https://doi.org/10.5194/esd-11-579-2020, https://doi.org/10.5194/esd-11-579-2020, 2020
Short summary
Short summary
This paper introduces new geoengineering model experiments as part of a larger model intercomparison effort, using reflective particles to block some of the incoming solar radiation to reach surface temperature targets. Outcomes of these applications are contrasted based on a high greenhouse gas emission pathway and a pathway with strong mitigation and negative emissions after 2040. We compare quantities that matter for societal and ecosystem impacts between the different scenarios.
Daniele Visioni, Giovanni Pitari, Vincenzo Rizi, Marco Iarlori, Irene Cionni, Ilaria Quaglia, Hideharu Akiyoshi, Slimane Bekki, Neal Butchart, Martin Chipperfield, Makoto Deushi, Sandip S. Dhomse, Rolando Garcia, Patrick Joeckel, Douglas Kinnison, Jean-François Lamarque, Marion Marchand, Martine Michou, Olaf Morgenstern, Tatsuya Nagashima, Fiona M. O'Connor, Luke D. Oman, David Plummer, Eugene Rozanov, David Saint-Martin, Robyn Schofield, John Scinocca, Andrea Stenke, Kane Stone, Kengo Sudo, Taichu Y. Tanaka, Simone Tilmes, Holger Tost, Yousuke Yamashita, and Guang Zeng
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-525, https://doi.org/10.5194/acp-2020-525, 2020
Preprint withdrawn
Short summary
Short summary
In this work we analyse the trend in ozone profiles taken at L'Aquila (Italy, 42.4° N) for seventeen years, between 2000 and 2016 and compare them against already available measured ozone trends. We try to understand and explain the observed trends at various heights in light of the simulations from seventeen different model, highlighting the contribution of changes in circulation and chemical ozone loss during this time period.
Monika E. Szeląg, Viktoria F. Sofieva, Doug Degenstein, Chris Roth, Sean Davis, and Lucien Froidevaux
Atmos. Chem. Phys., 20, 7035–7047, https://doi.org/10.5194/acp-20-7035-2020, https://doi.org/10.5194/acp-20-7035-2020, 2020
Short summary
Short summary
We analyze seasonal dependence of stratospheric ozone trends over 2000–2018. We demonstrate that the mid-latitude upper stratospheric ozone recovery maximizes during local winters and equinoxes. In the tropics, a very strong seasonal dependence of ozone trends is observed at all altitudes. We found hemispheric asymmetry of summertime ozone trend patterns below 35 km. The seasonal dependence of ozone trends and stratospheric temperature trends shows a clear inter-relation of the trend patterns.
Kevin M. Grise and Sean M. Davis
Atmos. Chem. Phys., 20, 5249–5268, https://doi.org/10.5194/acp-20-5249-2020, https://doi.org/10.5194/acp-20-5249-2020, 2020
Short summary
Short summary
As Earth's climate warms, the tropical overturning circulation (Hadley circulation) is projected to expand, potentially pushing subtropical dry zones further poleward. This study examines projections of the Hadley circulation from the latest generation of computer models and finds several notable differences from older models. For example, the Northern Hemisphere circulation has expanded northward at a greater rate in recent decades than would be expected from increasing greenhouse gases alone.
Alma Hodzic, Pedro Campuzano-Jost, Huisheng Bian, Mian Chin, Peter R. Colarco, Douglas A. Day, Karl D. Froyd, Bernd Heinold, Duseong S. Jo, Joseph M. Katich, John K. Kodros, Benjamin A. Nault, Jeffrey R. Pierce, Eric Ray, Jacob Schacht, Gregory P. Schill, Jason C. Schroder, Joshua P. Schwarz, Donna T. Sueper, Ina Tegen, Simone Tilmes, Kostas Tsigaridis, Pengfei Yu, and Jose L. Jimenez
Atmos. Chem. Phys., 20, 4607–4635, https://doi.org/10.5194/acp-20-4607-2020, https://doi.org/10.5194/acp-20-4607-2020, 2020
Short summary
Short summary
Organic aerosol (OA) is a key source of uncertainty in aerosol climate effects. We present the first pole-to-pole OA characterization during the NASA Atmospheric Tomography aircraft mission. OA has a strong seasonal and zonal variability, with the highest levels in summer and over fire-influenced regions and the lowest ones in the southern high latitudes. We show that global models predict the OA distribution well but not the relative contribution of OA emissions vs. chemical production.
Nicholas A. Davis, Sean M. Davis, Robert W. Portmann, Eric Ray, Karen H. Rosenlof, and Pengfei Yu
Geosci. Model Dev., 13, 717–734, https://doi.org/10.5194/gmd-13-717-2020, https://doi.org/10.5194/gmd-13-717-2020, 2020
Short summary
Short summary
Large-scale waves drive upward motion in the tropical stratosphere, with major impacts on stratospheric chemistry and climate. However, some of the modeling methods which attempt to simulate the past evolution of the stratosphere do not seem to be able to recreate important trends. We believe this is due to disagreements between the basic climate of the model and observations, but if the method is constructed more carefully, the disagreement becomes smaller and the trends become more realistic.
Julie M. Nicely, Bryan N. Duncan, Thomas F. Hanisco, Glenn M. Wolfe, Ross J. Salawitch, Makoto Deushi, Amund S. Haslerud, Patrick Jöckel, Béatrice Josse, Douglas E. Kinnison, Andrew Klekociuk, Michael E. Manyin, Virginie Marécal, Olaf Morgenstern, Lee T. Murray, Gunnar Myhre, Luke D. Oman, Giovanni Pitari, Andrea Pozzer, Ilaria Quaglia, Laura E. Revell, Eugene Rozanov, Andrea Stenke, Kane Stone, Susan Strahan, Simone Tilmes, Holger Tost, Daniel M. Westervelt, and Guang Zeng
Atmos. Chem. Phys., 20, 1341–1361, https://doi.org/10.5194/acp-20-1341-2020, https://doi.org/10.5194/acp-20-1341-2020, 2020
Short summary
Short summary
Differences in methane lifetime among global models are large and poorly understood. We use a neural network method and simulations from the Chemistry Climate Model Initiative to quantify the factors influencing methane lifetime spread among models and variations over time. UV photolysis, tropospheric ozone, and nitrogen oxides drive large model differences, while the same factors plus specific humidity contribute to a decreasing trend in methane lifetime between 1980 and 2015.
Susann Tegtmeier, James Anstey, Sean Davis, Rossana Dragani, Yayoi Harada, Ioana Ivanciu, Robin Pilch Kedzierski, Kirstin Krüger, Bernard Legras, Craig Long, James S. Wang, Krzysztof Wargan, and Jonathon S. Wright
Atmos. Chem. Phys., 20, 753–770, https://doi.org/10.5194/acp-20-753-2020, https://doi.org/10.5194/acp-20-753-2020, 2020
Short summary
Short summary
The tropical tropopause layer is an important atmospheric region right in between the troposphere and the stratosphere. We evaluate the representation of this layer in reanalyses data sets, which create a complete picture of the state of Earth's atmosphere using atmospheric modeling and available observations. The recent reanalyses show realistic temperatures in the tropical tropopause layer. However, where the temperature is lowest, the so-called cold point, the reanalyses are too cold.
Elizabeth Asher, Rebecca S. Hornbrook, Britton B. Stephens, Doug Kinnison, Eric J. Morgan, Ralph F. Keeling, Elliot L. Atlas, Sue M. Schauffler, Simone Tilmes, Eric A. Kort, Martin S. Hoecker-Martínez, Matt C. Long, Jean-François Lamarque, Alfonso Saiz-Lopez, Kathryn McKain, Colm Sweeney, Alan J. Hills, and Eric C. Apel
Atmos. Chem. Phys., 19, 14071–14090, https://doi.org/10.5194/acp-19-14071-2019, https://doi.org/10.5194/acp-19-14071-2019, 2019
Short summary
Short summary
Halogenated organic trace gases, which are a source of reactive halogens to the atmosphere, exert a disproportionately large influence on atmospheric chemistry and climate. This paper reports novel aircraft observations of halogenated compounds over the Southern Ocean in summer and evaluates hypothesized regional sources and emissions of these trace gases through their relationships to additional aircraft observations.
Yuanhong Zhao, Marielle Saunois, Philippe Bousquet, Xin Lin, Antoine Berchet, Michaela I. Hegglin, Josep G. Canadell, Robert B. Jackson, Didier A. Hauglustaine, Sophie Szopa, Ann R. Stavert, Nathan Luke Abraham, Alex T. Archibald, Slimane Bekki, Makoto Deushi, Patrick Jöckel, Béatrice Josse, Douglas Kinnison, Ole Kirner, Virginie Marécal, Fiona M. O'Connor, David A. Plummer, Laura E. Revell, Eugene Rozanov, Andrea Stenke, Sarah Strode, Simone Tilmes, Edward J. Dlugokencky, and Bo Zheng
Atmos. Chem. Phys., 19, 13701–13723, https://doi.org/10.5194/acp-19-13701-2019, https://doi.org/10.5194/acp-19-13701-2019, 2019
Short summary
Short summary
The role of hydroxyl radical changes in methane trends is debated, hindering our understanding of the methane cycle. This study quantifies how uncertainties in the hydroxyl radical may influence methane abundance in the atmosphere based on the inter-model comparison of hydroxyl radical fields and model simulations of CH4 abundance with different hydroxyl radical scenarios during 2000–2016. We show that hydroxyl radical changes could contribute up to 54 % of model-simulated methane biases.
Wenxiu Sun, Peter Hess, Gang Chen, and Simone Tilmes
Atmos. Chem. Phys., 19, 12917–12933, https://doi.org/10.5194/acp-19-12917-2019, https://doi.org/10.5194/acp-19-12917-2019, 2019
Short summary
Short summary
Using both observations and a chemistry climate–model we establish that in most locations changes in the waviness of the 500 hPa flow field, as measured by the local anticyclonic wave activity (AWA), explain a significant fraction of the interannual variability in surface ozone over the United States. In addition, we find that the change in AWA in a future climate (circa 2100) is predicted to cause a change in surface ozone ranging between –6 ppb and 6 ppb.
William T. Ball, Justin Alsing, Johannes Staehelin, Sean M. Davis, Lucien Froidevaux, and Thomas Peter
Atmos. Chem. Phys., 19, 12731–12748, https://doi.org/10.5194/acp-19-12731-2019, https://doi.org/10.5194/acp-19-12731-2019, 2019
Short summary
Short summary
We analyse long-term stratospheric ozone (60° S–60° N) trends over the 1985–2018 period. Previous work has suggested that lower stratosphere ozone declined over 1998–2016. We demonstrate that a large ozone upsurge in 2017 is likely related to QBO variability, but that lower stratospheric ozone trends likely remain lower in 2018 than in 1998. Tropical stratospheric ozone (30° S–30° N) shows highly probable decreases in both the lower stratosphere and in the integrated stratospheric ozone layer.
Ohad Harari, Chaim I. Garfinkel, Shlomi Ziskin Ziv, Olaf Morgenstern, Guang Zeng, Simone Tilmes, Douglas Kinnison, Makoto Deushi, Patrick Jöckel, Andrea Pozzer, Fiona M. O'Connor, and Sean Davis
Atmos. Chem. Phys., 19, 9253–9268, https://doi.org/10.5194/acp-19-9253-2019, https://doi.org/10.5194/acp-19-9253-2019, 2019
Short summary
Short summary
Ozone depletion in the Antarctic has been shown to influence surface conditions, but the effects of ozone depletion in the Arctic on surface climate are unclear. We show that Arctic ozone does influence surface climate in both polar regions and tropical regions, though the proximate cause of these surface impacts is not yet clear.
Huang Yang, Darryn W. Waugh, Clara Orbe, Guang Zeng, Olaf Morgenstern, Douglas E. Kinnison, Jean-Francois Lamarque, Simone Tilmes, David A. Plummer, Patrick Jöckel, Susan E. Strahan, Kane A. Stone, and Robyn Schofield
Atmos. Chem. Phys., 19, 5511–5528, https://doi.org/10.5194/acp-19-5511-2019, https://doi.org/10.5194/acp-19-5511-2019, 2019
Short summary
Short summary
We evaluate the performance of a suite of models in simulating the large-scale transport from the northern midlatitudes to the Arctic using a CO-like idealized tracer. We find a large multi-model spread of the Arctic concentration of this CO-like tracer that is well correlated with the differences in the location of the midlatitude jet as well as the northern Hadley Cell edge. Our results suggest the Hadley Cell is key and zonal-mean transport by surface meridional flow needs better constraint.
Laura E. Revell, Andrea Stenke, Fiona Tummon, Aryeh Feinberg, Eugene Rozanov, Thomas Peter, N. Luke Abraham, Hideharu Akiyoshi, Alexander T. Archibald, Neal Butchart, Makoto Deushi, Patrick Jöckel, Douglas Kinnison, Martine Michou, Olaf Morgenstern, Fiona M. O'Connor, Luke D. Oman, Giovanni Pitari, David A. Plummer, Robyn Schofield, Kane Stone, Simone Tilmes, Daniele Visioni, Yousuke Yamashita, and Guang Zeng
Atmos. Chem. Phys., 18, 16155–16172, https://doi.org/10.5194/acp-18-16155-2018, https://doi.org/10.5194/acp-18-16155-2018, 2018
Short summary
Short summary
Global models such as those participating in the Chemistry-Climate Model Initiative (CCMI) consistently simulate biases in tropospheric ozone compared with observations. We performed an advanced statistical analysis with one of the CCMI models to understand the cause of the bias. We found that emissions of ozone precursor gases are the dominant driver of the bias, implying either that the emissions are too large, or that the way in which the model handles emissions needs to be improved.
Xinyi Dong, Joshua S. Fu, Qingzhao Zhu, Jian Sun, Jiani Tan, Terry Keating, Takashi Sekiya, Kengo Sudo, Louisa Emmons, Simone Tilmes, Jan Eiof Jonson, Michael Schulz, Huisheng Bian, Mian Chin, Yanko Davila, Daven Henze, Toshihiko Takemura, Anna Maria Katarina Benedictow, and Kan Huang
Atmos. Chem. Phys., 18, 15581–15600, https://doi.org/10.5194/acp-18-15581-2018, https://doi.org/10.5194/acp-18-15581-2018, 2018
Short summary
Short summary
We have applied the HTAP phase II multi-model data to investigate the long-range transport impacts on surface concentration and column density of PM from Europe and Russia, Belarus, and Ukraine to eastern Asia, with a special focus on the long-range transport contribution during haze episodes in China. We found that long-range transport plays a more important role in elevating the background concentration of surface PM during the haze days.
Ori Adam, Kevin M. Grise, Paul Staten, Isla R. Simpson, Sean M. Davis, Nicholas A. Davis, Darryn W. Waugh, Thomas Birner, and Alison Ming
Geosci. Model Dev., 11, 4339–4357, https://doi.org/10.5194/gmd-11-4339-2018, https://doi.org/10.5194/gmd-11-4339-2018, 2018
Short summary
Short summary
Due to incoherent methodologies, estimates of tropical width variations differ significantly across studies. Here, methods for eight commonly-used metrics of the tropical width are implemented in the Tropical-width Diagnostics (TropD) code package. The method compilation and analysis provide tools and information which help reduce the methodological component of the uncertainty associated with calculations of the tropical width.
Daniele Visioni, Giovanni Pitari, Glauco di Genova, Simone Tilmes, and Irene Cionni
Atmos. Chem. Phys., 18, 14867–14887, https://doi.org/10.5194/acp-18-14867-2018, https://doi.org/10.5194/acp-18-14867-2018, 2018
Short summary
Short summary
Many side effects of sulfate geoengineering have to be analyzed before the world can even consider deploying this method of solar radiation management. In particular, we show that ice clouds in the upper troposphere are modified by a sulfate injection, producing a change that (by allowing for more planetary radiation to escape to space) would produce a further cooling. This might be important when considering the necessary amount of sulfate that needs to be injected to achieve a certain target.
Benjamin Brown-Steiner, Noelle E. Selin, Ronald Prinn, Simone Tilmes, Louisa Emmons, Jean-François Lamarque, and Philip Cameron-Smith
Geosci. Model Dev., 11, 4155–4174, https://doi.org/10.5194/gmd-11-4155-2018, https://doi.org/10.5194/gmd-11-4155-2018, 2018
Short summary
Short summary
We conduct three simulations of atmospheric chemistry using chemical mechanisms of different levels of complexity and compare their results to observations. We explore situations in which the simplified mechanisms match the output of the most complex mechanism, as well as when they diverge. We investigate how concurrent utilization of chemical mechanisms of different complexities can further our atmospheric-chemistry understanding at various scales and give some strategies for future research.
Mohamadou Diallo, Martin Riese, Thomas Birner, Paul Konopka, Rolf Müller, Michaela I. Hegglin, Michelle L. Santee, Mark Baldwin, Bernard Legras, and Felix Ploeger
Atmos. Chem. Phys., 18, 13055–13073, https://doi.org/10.5194/acp-18-13055-2018, https://doi.org/10.5194/acp-18-13055-2018, 2018
Short summary
Short summary
The unprecedented timing of an El Niño event aligned with the disrupted QBO in 2015–2016 caused a perturbation to the stratospheric circulation, affecting trace gases. This paper resolves the puzzling response of the lower stratospheric water vapor by showing that the QBO disruption reversed the lower stratosphere moistening triggered by the alignment of the El Niño event with a westerly QBO in early boreal winter.
Jiani Tan, Joshua S. Fu, Frank Dentener, Jian Sun, Louisa Emmons, Simone Tilmes, Johannes Flemming, Toshihiko Takemura, Huisheng Bian, Qingzhao Zhu, Cheng-En Yang, and Terry Keating
Atmos. Chem. Phys., 18, 12223–12240, https://doi.org/10.5194/acp-18-12223-2018, https://doi.org/10.5194/acp-18-12223-2018, 2018
Short summary
Short summary
Have contributions of hemispheric air pollution to deposition at global scale been overlooked in the past years? How do we assess the critical load for the acid deposition when we look for the demand of forest and crop? This study highlights the significant impact of hemispheric transport on deposition in coastal regions, open ocean and low-emission regions. Further research is proposed for improving ecosystem and human health in these regions, with regards to the enhanced hemispheric transport.
Pakawat Phalitnonkiat, Peter G. M. Hess, Mircea D. Grigoriu, Gennady Samorodnitsky, Wenxiu Sun, Ellie Beaudry, Simone Tilmes, Makato Deushi, Beatrice Josse, David Plummer, and Kengo Sudo
Atmos. Chem. Phys., 18, 11927–11948, https://doi.org/10.5194/acp-18-11927-2018, https://doi.org/10.5194/acp-18-11927-2018, 2018
Short summary
Short summary
The co-occurrence of heat waves and pollution events and the resulting high mortality rates emphasize the importance of the co-occurrence of pollution and temperature extremes. We analyze ozone and temperature extremes and their joint occurrence over the United States during the summer months (JJA) in measurement data and in model simulations of the present and future climates.
Birgit Hassler, Stefanie Kremser, Greg E. Bodeker, Jared Lewis, Kage Nesbit, Sean M. Davis, Martyn P. Chipperfield, Sandip S. Dhomse, and Martin Dameris
Earth Syst. Sci. Data, 10, 1473–1490, https://doi.org/10.5194/essd-10-1473-2018, https://doi.org/10.5194/essd-10-1473-2018, 2018
Steven T. Turnock, Oliver Wild, Frank J. Dentener, Yanko Davila, Louisa K. Emmons, Johannes Flemming, Gerd A. Folberth, Daven K. Henze, Jan E. Jonson, Terry J. Keating, Sudo Kengo, Meiyun Lin, Marianne Lund, Simone Tilmes, and Fiona M. O'Connor
Atmos. Chem. Phys., 18, 8953–8978, https://doi.org/10.5194/acp-18-8953-2018, https://doi.org/10.5194/acp-18-8953-2018, 2018
Short summary
Short summary
A simple parameterisation was developed in this study to provide a rapid assessment of the impacts and uncertainties associated with future emission control strategies by predicting changes to surface ozone air quality and near-term climate forcing of ozone. Future emissions scenarios based on currently implemented legislation are shown to worsen surface ozone air quality and enhance near-term climate warming, with changes in methane becoming increasingly important in the future.
Benjamin Brown-Steiner, Noelle E. Selin, Ronald G. Prinn, Erwan Monier, Simone Tilmes, Louisa Emmons, and Fernando Garcia-Menendez
Atmos. Chem. Phys., 18, 8373–8388, https://doi.org/10.5194/acp-18-8373-2018, https://doi.org/10.5194/acp-18-8373-2018, 2018
Short summary
Short summary
Detecting signals in observations and simulations of atmospheric chemistry is difficult due to the underlying variability in the chemistry, meteorology, and climatology. Here we examine the scale dependence of ozone variability and explore strategies for reducing or averaging this variability and thereby enhancing ozone signal detection capabilities. We find that 10–15 years of temporal averaging, and some level of spatial averaging, reduces the risk of overconfidence in ozone signals.
Sandip S. Dhomse, Douglas Kinnison, Martyn P. Chipperfield, Ross J. Salawitch, Irene Cionni, Michaela I. Hegglin, N. Luke Abraham, Hideharu Akiyoshi, Alex T. Archibald, Ewa M. Bednarz, Slimane Bekki, Peter Braesicke, Neal Butchart, Martin Dameris, Makoto Deushi, Stacey Frith, Steven C. Hardiman, Birgit Hassler, Larry W. Horowitz, Rong-Ming Hu, Patrick Jöckel, Beatrice Josse, Oliver Kirner, Stefanie Kremser, Ulrike Langematz, Jared Lewis, Marion Marchand, Meiyun Lin, Eva Mancini, Virginie Marécal, Martine Michou, Olaf Morgenstern, Fiona M. O'Connor, Luke Oman, Giovanni Pitari, David A. Plummer, John A. Pyle, Laura E. Revell, Eugene Rozanov, Robyn Schofield, Andrea Stenke, Kane Stone, Kengo Sudo, Simone Tilmes, Daniele Visioni, Yousuke Yamashita, and Guang Zeng
Atmos. Chem. Phys., 18, 8409–8438, https://doi.org/10.5194/acp-18-8409-2018, https://doi.org/10.5194/acp-18-8409-2018, 2018
Short summary
Short summary
We analyse simulations from the Chemistry-Climate Model Initiative (CCMI) to estimate the return dates of the stratospheric ozone layer from depletion by anthropogenic chlorine and bromine. The simulations from 20 models project that global column ozone will return to 1980 values in 2047 (uncertainty range 2042–2052). Return dates in other regions vary depending on factors related to climate change and importance of chlorine and bromine. Column ozone in the tropics may continue to decline.
Xiaokang Wu, Huang Yang, Darryn W. Waugh, Clara Orbe, Simone Tilmes, and Jean-Francois Lamarque
Atmos. Chem. Phys., 18, 7439–7452, https://doi.org/10.5194/acp-18-7439-2018, https://doi.org/10.5194/acp-18-7439-2018, 2018
Short summary
Short summary
The seasonal and interannual variability of transport times from northern mid-latitudes into the southern hemisphere is examined using simulations of
agetracers. The largest variability occurs near the surface close to the tropical convergence zones, but the peak is further south and there is a smaller tropical–extratropical contrast for tracers with more rapid loss. Hence the variability of trace gases in the southern extratropics will vary with their chemical lifetime.
Clara Orbe, Huang Yang, Darryn W. Waugh, Guang Zeng, Olaf Morgenstern, Douglas E. Kinnison, Jean-Francois Lamarque, Simone Tilmes, David A. Plummer, John F. Scinocca, Beatrice Josse, Virginie Marecal, Patrick Jöckel, Luke D. Oman, Susan E. Strahan, Makoto Deushi, Taichu Y. Tanaka, Kohei Yoshida, Hideharu Akiyoshi, Yousuke Yamashita, Andreas Stenke, Laura Revell, Timofei Sukhodolov, Eugene Rozanov, Giovanni Pitari, Daniele Visioni, Kane A. Stone, Robyn Schofield, and Antara Banerjee
Atmos. Chem. Phys., 18, 7217–7235, https://doi.org/10.5194/acp-18-7217-2018, https://doi.org/10.5194/acp-18-7217-2018, 2018
Short summary
Short summary
In this study we compare a few atmospheric transport properties among several numerical models that are used to study the influence of atmospheric chemistry on climate. We show that there are large differences among models in terms of the timescales that connect the Northern Hemisphere midlatitudes, where greenhouse gases and ozone-depleting substances are emitted, to the Southern Hemisphere. Our results may have important implications for how models represent atmospheric composition.
Jiani Tan, Joshua S. Fu, Frank Dentener, Jian Sun, Louisa Emmons, Simone Tilmes, Kengo Sudo, Johannes Flemming, Jan Eiof Jonson, Sylvie Gravel, Huisheng Bian, Yanko Davila, Daven K. Henze, Marianne T. Lund, Tom Kucsera, Toshihiko Takemura, and Terry Keating
Atmos. Chem. Phys., 18, 6847–6866, https://doi.org/10.5194/acp-18-6847-2018, https://doi.org/10.5194/acp-18-6847-2018, 2018
Short summary
Short summary
We study the distributions of sulfur and nitrogen deposition, which are associated with current environmental issues such as formation of acid rain and ecosystem eutrophication and result in widespread problems such as loss of environmental diversity, harming the crop yield and even food insecurity. According to our study, both the amount and distribution of sulfate and nitrogen deposition have changed significantly in the last decade, particularly in East Asia, South Asia and Southeast Asia.
Chaim I. Garfinkel, Amit Gordon, Luke D. Oman, Feng Li, Sean Davis, and Steven Pawson
Atmos. Chem. Phys., 18, 4597–4615, https://doi.org/10.5194/acp-18-4597-2018, https://doi.org/10.5194/acp-18-4597-2018, 2018
Short summary
Short summary
The impact of El Niño in the lower stratosphere is nonlinear in spring. While moderate El Niño events lead to cooling in this region,
strong El Niño events appear to lead to warming, and hence the water vapor response is nonlinear too. The net effect is that strong
El Nino events, such as in 1997/1998 and 2015/2016, lead to qualitatively different water vapor impacts as compared to moderate
El Nino events.
Lauren Marshall, Anja Schmidt, Matthew Toohey, Ken S. Carslaw, Graham W. Mann, Michael Sigl, Myriam Khodri, Claudia Timmreck, Davide Zanchettin, William T. Ball, Slimane Bekki, James S. A. Brooke, Sandip Dhomse, Colin Johnson, Jean-Francois Lamarque, Allegra N. LeGrande, Michael J. Mills, Ulrike Niemeier, James O. Pope, Virginie Poulain, Alan Robock, Eugene Rozanov, Andrea Stenke, Timofei Sukhodolov, Simone Tilmes, Kostas Tsigaridis, and Fiona Tummon
Atmos. Chem. Phys., 18, 2307–2328, https://doi.org/10.5194/acp-18-2307-2018, https://doi.org/10.5194/acp-18-2307-2018, 2018
Short summary
Short summary
We use four global aerosol models to compare the simulated sulfate deposition from the 1815 Mt. Tambora eruption to ice core records. Inter-model volcanic sulfate deposition differs considerably. Volcanic sulfate deposited on polar ice sheets is used to estimate the atmospheric sulfate burden and subsequently radiative forcing of historic eruptions. Our results suggest that deriving such relationships from model simulations may be associated with greater uncertainties than previously thought.
William T. Ball, Justin Alsing, Daniel J. Mortlock, Johannes Staehelin, Joanna D. Haigh, Thomas Peter, Fiona Tummon, Rene Stübi, Andrea Stenke, John Anderson, Adam Bourassa, Sean M. Davis, Doug Degenstein, Stacey Frith, Lucien Froidevaux, Chris Roth, Viktoria Sofieva, Ray Wang, Jeannette Wild, Pengfei Yu, Jerald R. Ziemke, and Eugene V. Rozanov
Atmos. Chem. Phys., 18, 1379–1394, https://doi.org/10.5194/acp-18-1379-2018, https://doi.org/10.5194/acp-18-1379-2018, 2018
Short summary
Short summary
Using a robust analysis, with artefact-corrected ozone data, we confirm upper stratospheric ozone is recovering following the Montreal Protocol, but that lower stratospheric ozone (50° S–50° N) has continued to decrease since 1998, and the ozone layer as a whole (60° S–60° N) may be lower today than in 1998. No change in total column ozone may be due to increasing tropospheric ozone. State-of-the-art models do not reproduce lower stratospheric ozone decreases.
Craig S. Long, Masatomo Fujiwara, Sean Davis, Daniel M. Mitchell, and Corwin J. Wright
Atmos. Chem. Phys., 17, 14593–14629, https://doi.org/10.5194/acp-17-14593-2017, https://doi.org/10.5194/acp-17-14593-2017, 2017
Short summary
Short summary
As part of the SPARC Reanalysis Intercomparison Project, we evaluate the temperature and wind structure of all the recent and past reanalyses with 2.5-degree monthly zonal mean data sets from 1979–2014. There is a distinct change in the temperature structure in the stratosphere in 1998. Zonal winds are in greater agreement than temperatures. All reanalyses have issues analysing the tropical stratospheric winds. Caution is advised for using reanalysis temperatures for trend detection.
Sean M. Davis, Michaela I. Hegglin, Masatomo Fujiwara, Rossana Dragani, Yayoi Harada, Chiaki Kobayashi, Craig Long, Gloria L. Manney, Eric R. Nash, Gerald L. Potter, Susann Tegtmeier, Tao Wang, Krzysztof Wargan, and Jonathon S. Wright
Atmos. Chem. Phys., 17, 12743–12778, https://doi.org/10.5194/acp-17-12743-2017, https://doi.org/10.5194/acp-17-12743-2017, 2017
Short summary
Short summary
Ozone and water vapor in the stratosphere are important gases that affect surface climate and absorb incoming solar ultraviolet radiation. These gases are represented in reanalyses, which create a complete picture of the state of Earth's atmosphere using limited observations. We evaluate reanalysis water vapor and ozone fidelity by intercomparing them, and comparing them to independent observations. Generally reanalyses do a good job at representing ozone, but have problems with water vapor.
Lili Xia, Peer J. Nowack, Simone Tilmes, and Alan Robock
Atmos. Chem. Phys., 17, 11913–11928, https://doi.org/10.5194/acp-17-11913-2017, https://doi.org/10.5194/acp-17-11913-2017, 2017
Short summary
Short summary
Ozone is a key air pollutant. We model two geoengineering schemes, stratospheric sulfur injection and solar irradiance reduction, to compare their impacts on atmospheric ozone concentrations. With the nearly identical global mean surface temperature reduction, solar dimming increases global average surface ozone concentration, while sulfate injection decreases it. This difference is due to different stratosphere–troposphere exchange of ozone and tropospheric ozone chemistry in the two scenarios.
Daniele Visioni, Giovanni Pitari, Valentina Aquila, Simone Tilmes, Irene Cionni, Glauco Di Genova, and Eva Mancini
Atmos. Chem. Phys., 17, 11209–11226, https://doi.org/10.5194/acp-17-11209-2017, https://doi.org/10.5194/acp-17-11209-2017, 2017
Short summary
Short summary
Sulfate geoengineering (SG), the sustained injection of SO2 in the lower stratosphere, is being discussed as a way to counterbalance surface warming, mimicking volcanic eruptions. In this paper, we analyse results from two models part of the GeoMIP project in order to understand the effect SG might have on the concentration and lifetime of methane, which acts in the atmosphere as a greenhouse gas. Understanding possible side effects of SG is a crucial step if its viability is to be assessed.
Wolfgang Steinbrecht, Lucien Froidevaux, Ryan Fuller, Ray Wang, John Anderson, Chris Roth, Adam Bourassa, Doug Degenstein, Robert Damadeo, Joe Zawodny, Stacey Frith, Richard McPeters, Pawan Bhartia, Jeannette Wild, Craig Long, Sean Davis, Karen Rosenlof, Viktoria Sofieva, Kaley Walker, Nabiz Rahpoe, Alexei Rozanov, Mark Weber, Alexandra Laeng, Thomas von Clarmann, Gabriele Stiller, Natalya Kramarova, Sophie Godin-Beekmann, Thierry Leblanc, Richard Querel, Daan Swart, Ian Boyd, Klemens Hocke, Niklaus Kämpfer, Eliane Maillard Barras, Lorena Moreira, Gerald Nedoluha, Corinne Vigouroux, Thomas Blumenstock, Matthias Schneider, Omaira García, Nicholas Jones, Emmanuel Mahieu, Dan Smale, Michael Kotkamp, John Robinson, Irina Petropavlovskikh, Neil Harris, Birgit Hassler, Daan Hubert, and Fiona Tummon
Atmos. Chem. Phys., 17, 10675–10690, https://doi.org/10.5194/acp-17-10675-2017, https://doi.org/10.5194/acp-17-10675-2017, 2017
Short summary
Short summary
Thanks to the 1987 Montreal Protocol and its amendments, ozone-depleting chlorine (and bromine) in the stratosphere has declined slowly since the late 1990s. Improved and extended long-term ozone profile observations from satellites and ground-based stations confirm that ozone is responding as expected and has increased by about 2 % per decade since 2000 in the upper stratosphere, around 40 km altitude. At lower altitudes, however, ozone has not changed significantly since 2000.
Maria A. Navarro, Alfonso Saiz-Lopez, Carlos A. Cuevas, Rafael P. Fernandez, Elliot Atlas, Xavier Rodriguez-Lloveras, Douglas Kinnison, Jean-Francois Lamarque, Simone Tilmes, Troy Thornberry, Andrew Rollins, James W. Elkins, Eric J. Hintsa, and Fred L. Moore
Atmos. Chem. Phys., 17, 9917–9930, https://doi.org/10.5194/acp-17-9917-2017, https://doi.org/10.5194/acp-17-9917-2017, 2017
Short summary
Short summary
Inorganic bromine (Bry) plays an important role in ozone layer depletion. Based on aircraft observations of organic bromine species and chemistry simulations, we model the Bry abundances over the Pacific tropical tropopause. Our results show BrO and Br as the dominant species during daytime hours, and BrCl and BrONO2 as the nighttime dominant species over the western and eastern Pacific, respectively. The difference in the partitioning is due to changes in the abundance of O3, NO2, and Cly.
Jeremiah P. Sjoberg, Thomas Birner, and Richard H. Johnson
Atmos. Chem. Phys., 17, 8971–8986, https://doi.org/10.5194/acp-17-8971-2017, https://doi.org/10.5194/acp-17-8971-2017, 2017
Short summary
Short summary
Observational estimates of tropical, large-scale fluxes of zonal momentum from troposphere to stratosphere remain challenging. We present an extended technique for estimating the daily amplitudes of these fluxes using data captured from balloon-borne radiosondes. Climatological analysis of our time series matches expectations of annual and interannual variability, indicating reliability in our estimates. Vertical resolution less than 1 km is found to be important for precise estimation.
Anne A. Glanville and Thomas Birner
Atmos. Chem. Phys., 17, 4337–4353, https://doi.org/10.5194/acp-17-4337-2017, https://doi.org/10.5194/acp-17-4337-2017, 2017
Short summary
Short summary
Nearly all air enters the stratosphere through the tropical tropopause, which exerts a control on stratospheric chemistry and climate. By combining satellite observations with a simple 1-D transport model, we study the roles of vertical and horizontal mixing in transport near the tropical tropopause. We find that vertical mixing may play a more significant role than previously assumed, which is potentially as important as slow vertical transport by the residual mass circulation.
Olaf Morgenstern, Michaela I. Hegglin, Eugene Rozanov, Fiona M. O'Connor, N. Luke Abraham, Hideharu Akiyoshi, Alexander T. Archibald, Slimane Bekki, Neal Butchart, Martyn P. Chipperfield, Makoto Deushi, Sandip S. Dhomse, Rolando R. Garcia, Steven C. Hardiman, Larry W. Horowitz, Patrick Jöckel, Beatrice Josse, Douglas Kinnison, Meiyun Lin, Eva Mancini, Michael E. Manyin, Marion Marchand, Virginie Marécal, Martine Michou, Luke D. Oman, Giovanni Pitari, David A. Plummer, Laura E. Revell, David Saint-Martin, Robyn Schofield, Andrea Stenke, Kane Stone, Kengo Sudo, Taichu Y. Tanaka, Simone Tilmes, Yousuke Yamashita, Kohei Yoshida, and Guang Zeng
Geosci. Model Dev., 10, 639–671, https://doi.org/10.5194/gmd-10-639-2017, https://doi.org/10.5194/gmd-10-639-2017, 2017
Short summary
Short summary
We present a review of the make-up of 20 models participating in the Chemistry–Climate Model Initiative (CCMI). In comparison to earlier such activities, most of these models comprise a whole-atmosphere chemistry, and several of them include an interactive ocean module. This makes them suitable for studying the interactions of tropospheric air quality, stratospheric ozone, and climate. The paper lays the foundation for other studies using the CCMI simulations for scientific analysis.
Amy H. Butler, Jeremiah P. Sjoberg, Dian J. Seidel, and Karen H. Rosenlof
Earth Syst. Sci. Data, 9, 63–76, https://doi.org/10.5194/essd-9-63-2017, https://doi.org/10.5194/essd-9-63-2017, 2017
Short summary
Short summary
From six different reanalysis products, we created a new comprehensive database of major sudden stratospheric warming events, which are large and rapid temperature increases in the stratosphere associated with a reversal of the stratospheric winter circulation. This new database can facilitate analysis of the evolution and surface impacts of these events as well as intercomparison of reanalysis products.
Rafael P. Fernandez, Douglas E. Kinnison, Jean-Francois Lamarque, Simone Tilmes, and Alfonso Saiz-Lopez
Atmos. Chem. Phys., 17, 1673–1688, https://doi.org/10.5194/acp-17-1673-2017, https://doi.org/10.5194/acp-17-1673-2017, 2017
Short summary
Short summary
The inclusion of biogenic very-short lived bromine (VSLBr) in a chemistry-climate model produces an expansion of the ozone hole area of ~ 5 million km2, which is equivalent in magnitude to the recently estimated Antarctic ozone healing due to the reduction of anthropogenic CFCs and halons. The maximum Antarctic ozone hole depletion increases by up to 14 % when natural VSLBr are considered, but does not introduce a significant delay of the modelled ozone return date to 1980 October levels.
Masatomo Fujiwara, Jonathon S. Wright, Gloria L. Manney, Lesley J. Gray, James Anstey, Thomas Birner, Sean Davis, Edwin P. Gerber, V. Lynn Harvey, Michaela I. Hegglin, Cameron R. Homeyer, John A. Knox, Kirstin Krüger, Alyn Lambert, Craig S. Long, Patrick Martineau, Andrea Molod, Beatriz M. Monge-Sanz, Michelle L. Santee, Susann Tegtmeier, Simon Chabrillat, David G. H. Tan, David R. Jackson, Saroja Polavarapu, Gilbert P. Compo, Rossana Dragani, Wesley Ebisuzaki, Yayoi Harada, Chiaki Kobayashi, Will McCarty, Kazutoshi Onogi, Steven Pawson, Adrian Simmons, Krzysztof Wargan, Jeffrey S. Whitaker, and Cheng-Zhi Zou
Atmos. Chem. Phys., 17, 1417–1452, https://doi.org/10.5194/acp-17-1417-2017, https://doi.org/10.5194/acp-17-1417-2017, 2017
Short summary
Short summary
We introduce the SPARC Reanalysis Intercomparison Project (S-RIP), review key concepts and elements of atmospheric reanalysis systems, and summarize the technical details of and differences among 11 of these systems. This work supports scientific studies and intercomparisons of reanalysis products by collecting these background materials and technical details into a single reference. We also address several common misunderstandings and points of confusion regarding reanalyses.
Michael R. Giordano, Lars E. Kalnajs, Anita Avery, J. Douglas Goetz, Sean M. Davis, and Peter F. DeCarlo
Atmos. Chem. Phys., 17, 1–20, https://doi.org/10.5194/acp-17-1-2017, https://doi.org/10.5194/acp-17-1-2017, 2017
Short summary
Short summary
This paper summarizes two field measurements of particles and gases made in coastal Antarctica and represents the first real-time composition measurements of particles in this understudied area of the world. Using the combined data from both field measurements, we find that there is a constant background of particles in coastal Antarctica and that they are mostly sulfate. Seasonal transitions from winter to spring add additional particles, and that from spring to summer adds additional sulfate.
Camilla Weum Stjern, Bjørn Hallvard Samset, Gunnar Myhre, Huisheng Bian, Mian Chin, Yanko Davila, Frank Dentener, Louisa Emmons, Johannes Flemming, Amund Søvde Haslerud, Daven Henze, Jan Eiof Jonson, Tom Kucsera, Marianne Tronstad Lund, Michael Schulz, Kengo Sudo, Toshihiko Takemura, and Simone Tilmes
Atmos. Chem. Phys., 16, 13579–13599, https://doi.org/10.5194/acp-16-13579-2016, https://doi.org/10.5194/acp-16-13579-2016, 2016
Short summary
Short summary
Air pollution can reach distant regions through intercontinental transport. Here we first present results from the Hemispheric Transport of Air Pollution Phase 2 exercise, where many models performed the same set of coordinated emission-reduction experiments. We find that mitigations have considerable extra-regional effects, and show that this is particularly true for black carbon emissions, as long-range transport elevates aerosols to higher levels where their radiative influence is stronger.
Sean M. Davis, Karen H. Rosenlof, Birgit Hassler, Dale F. Hurst, William G. Read, Holger Vömel, Henry Selkirk, Masatomo Fujiwara, and Robert Damadeo
Earth Syst. Sci. Data, 8, 461–490, https://doi.org/10.5194/essd-8-461-2016, https://doi.org/10.5194/essd-8-461-2016, 2016
Short summary
Short summary
This paper describes the construction of the Stratospheric Water and Ozone Satellite Homogenized (SWOOSH) database, whose main feature is a combined data product created by homogenizing multiple satellite records. This motivation for SWOOSH is that in order to study multiyear to decadal variability in ozone and water vapor concentrations, it is necessary to have a continuous and smooth record without artificial jumps in the data.
Dale F. Hurst, William G. Read, Holger Vömel, Henry B. Selkirk, Karen H. Rosenlof, Sean M. Davis, Emrys G. Hall, Allen F. Jordan, and Samuel J. Oltmans
Atmos. Meas. Tech., 9, 4447–4457, https://doi.org/10.5194/amt-9-4447-2016, https://doi.org/10.5194/amt-9-4447-2016, 2016
Short summary
Short summary
This study compares stratospheric water vapor measurements by the Aura Microwave Limb Sounder (MLS) and balloon-borne frost point hygrometers (FPs) at five sites that launch two different types of FPs. The results demonstrate that FP and MLS measurements have been diverging at statistically significant rates of 0.6 to 1.5 % per year since approximately 2010. Similarities in the divergences at different sites suggest a positive drift in MLS retrievals since approximately 2010.
Felix Ploeger and Thomas Birner
Atmos. Chem. Phys., 16, 10195–10213, https://doi.org/10.5194/acp-16-10195-2016, https://doi.org/10.5194/acp-16-10195-2016, 2016
Short summary
Short summary
We investigate the aging of air in the stratosphere caused by transport due to Brewer's circulation, using the Boundary Impulse Evolving Response (BIER) method. The age spectra show multiple peaks caused by the seasonal and inter-annual variations of transport. The modal age is controlled by the residual circulation in the tropics and winter hemisphere extratropics and by mixing in the summer hemisphere. Analysis of the full age spectrum is strongly recommended for model inter-comparisons.
Sarah A. Strode, Helen M. Worden, Megan Damon, Anne R. Douglass, Bryan N. Duncan, Louisa K. Emmons, Jean-Francois Lamarque, Michael Manyin, Luke D. Oman, Jose M. Rodriguez, Susan E. Strahan, and Simone Tilmes
Atmos. Chem. Phys., 16, 7285–7294, https://doi.org/10.5194/acp-16-7285-2016, https://doi.org/10.5194/acp-16-7285-2016, 2016
Short summary
Short summary
We use global models to interpret trends in MOPITT observations of CO. Simulations with time-dependent emissions reproduce the observed trends over the eastern USA and Europe, suggesting that the emissions are reasonable for these regions. The simulations produce a positive trend over eastern China, contrary to the observed negative trend. This may indicate that the assumed emission trend over China is too positive. However, large variability in the overhead ozone column also contributes.
Simone Tilmes, Jean-Francois Lamarque, Louisa K. Emmons, Doug E. Kinnison, Dan Marsh, Rolando R. Garcia, Anne K. Smith, Ryan R. Neely, Andrew Conley, Francis Vitt, Maria Val Martin, Hiroshi Tanimoto, Isobel Simpson, Don R. Blake, and Nicola Blake
Geosci. Model Dev., 9, 1853–1890, https://doi.org/10.5194/gmd-9-1853-2016, https://doi.org/10.5194/gmd-9-1853-2016, 2016
Short summary
Short summary
The state of the art Community Earth System Model, CESM1 CAM4-chem has been used to perform reference and sensitivity simulations as part of the Chemistry Climate Model Initiative (CCMI). Specifics of the model and details regarding the setup of the simulations are described. In additions, the main behavior of the model, including selected chemical species have been evaluated with climatological datasets. This paper is therefore a references for studies that use the provided model results.
L. Xia, A. Robock, S. Tilmes, and R. R. Neely III
Atmos. Chem. Phys., 16, 1479–1489, https://doi.org/10.5194/acp-16-1479-2016, https://doi.org/10.5194/acp-16-1479-2016, 2016
Short summary
Short summary
Climate model simulations show that stratospheric sulfate geoengineering could impact the terrestrial carbon cycle by enhancing the carbon sink. Enhanced downward diffuse radiation, combined with cooling, could stimulate plants to grow more and absorb more carbon dioxide. This beneficial impact of stratospheric sulfate geoengineering would need to be balanced by a large number of potential risks in any future decisions about implementation of geoengineering.
X. Liu, P.-L. Ma, H. Wang, S. Tilmes, B. Singh, R. C. Easter, S. J. Ghan, and P. J. Rasch
Geosci. Model Dev., 9, 505–522, https://doi.org/10.5194/gmd-9-505-2016, https://doi.org/10.5194/gmd-9-505-2016, 2016
Short summary
Short summary
In this study, we describe and evaluate a new four-mode version of the Modal Aerosol Module (MAM4) in the Community Atmosphere Model version 5 (CAM5). Compared to the current three-mode version of MAM in CAM5, MAM4 significantly improves the simulation of seasonal variation of BC concentrations in the polar regions, by increasing the BC concentrations in all seasons and particularly in cold seasons.
J. He, Y. Zhang, S. Tilmes, L. Emmons, J.-F. Lamarque, T. Glotfelty, A. Hodzic, and F. Vitt
Geosci. Model Dev., 8, 3999–4025, https://doi.org/10.5194/gmd-8-3999-2015, https://doi.org/10.5194/gmd-8-3999-2015, 2015
Short summary
Short summary
The global simulations with CB05_GE and MOZART-4x predict similar chemical profiles for major gases compared to aircraft measurements, with better agreement for the NOy profile by CB05_GE. The SOA concentrations of SOA at four sites in CONUS and organic carbon over the IMPROVE sites are better predicted by MOZART-4x. The two simulations result in a global average difference of 0.5W m-2 in simulated shortwave cloud radiative forcing, with up to 13.6W m-2 over subtropical regions.
Y. Zheng, N. Unger, A. Hodzic, L. Emmons, C. Knote, S. Tilmes, J.-F. Lamarque, and P. Yu
Atmos. Chem. Phys., 15, 13487–13506, https://doi.org/10.5194/acp-15-13487-2015, https://doi.org/10.5194/acp-15-13487-2015, 2015
Short summary
Short summary
Nitrogen oxides (NOx) play an important but complex role in secondary organic aerosol (SOA) formation. In this study we update the SOA scheme in a global 3-D chemistry-climate model by implementing a 4-product volatility basis set (VBS) framework with NOx-dependent yields and simplified aging parameterizations. We find that the SOA decrease in response to a 50% reduction in anthropogenic NOx emissions is limited due to the buffering in different chemical pathways.
B. Kravitz, A. Robock, S. Tilmes, O. Boucher, J. M. English, P. J. Irvine, A. Jones, M. G. Lawrence, M. MacCracken, H. Muri, J. C. Moore, U. Niemeier, S. J. Phipps, J. Sillmann, T. Storelvmo, H. Wang, and S. Watanabe
Geosci. Model Dev., 8, 3379–3392, https://doi.org/10.5194/gmd-8-3379-2015, https://doi.org/10.5194/gmd-8-3379-2015, 2015
M. Gil-Ojeda, M. Navarro-Comas, L. Gómez-Martín, J. A. Adame, A. Saiz-Lopez, C. A. Cuevas, Y. González, O. Puentedura, E. Cuevas, J.-F. Lamarque, D. Kinninson, and S. Tilmes
Atmos. Chem. Phys., 15, 10567–10579, https://doi.org/10.5194/acp-15-10567-2015, https://doi.org/10.5194/acp-15-10567-2015, 2015
Short summary
Short summary
The NO2 seasonal evolution in the free troposphere (FT) has been established for the first time, based on a remote sensing technique (MAXDOAS) and thus avoiding the problems of the local pollution of in situ instruments. A clear seasonality has been found, with background levels of 20-40pptv. Evidence has been found on fast, direct injection of surface air into the free troposphere. This result might have implications on the FT distribution of halogens and other species with marine sources.
N. R. P. Harris, B. Hassler, F. Tummon, G. E. Bodeker, D. Hubert, I. Petropavlovskikh, W. Steinbrecht, J. Anderson, P. K. Bhartia, C. D. Boone, A. Bourassa, S. M. Davis, D. Degenstein, A. Delcloo, S. M. Frith, L. Froidevaux, S. Godin-Beekmann, N. Jones, M. J. Kurylo, E. Kyrölä, M. Laine, S. T. Leblanc, J.-C. Lambert, B. Liley, E. Mahieu, A. Maycock, M. de Mazière, A. Parrish, R. Querel, K. H. Rosenlof, C. Roth, C. Sioris, J. Staehelin, R. S. Stolarski, R. Stübi, J. Tamminen, C. Vigouroux, K. A. Walker, H. J. Wang, J. Wild, and J. M. Zawodny
Atmos. Chem. Phys., 15, 9965–9982, https://doi.org/10.5194/acp-15-9965-2015, https://doi.org/10.5194/acp-15-9965-2015, 2015
Short summary
Short summary
Trends in the vertical distribution of ozone are reported for new and recently revised data sets. The amount of ozone-depleting compounds in the stratosphere peaked in the second half of the 1990s. We examine the trends before and after that peak to see if any change in trend is discernible. The previously reported decreases are confirmed. Furthermore, the downward trend in upper stratospheric ozone has not continued. The possible significance of any increase is discussed in detail.
L. K. Emmons, S. R. Arnold, S. A. Monks, V. Huijnen, S. Tilmes, K. S. Law, J. L. Thomas, J.-C. Raut, I. Bouarar, S. Turquety, Y. Long, B. Duncan, S. Steenrod, S. Strode, J. Flemming, J. Mao, J. Langner, A. M. Thompson, D. Tarasick, E. C. Apel, D. R. Blake, R. C. Cohen, J. Dibb, G. S. Diskin, A. Fried, S. R. Hall, L. G. Huey, A. J. Weinheimer, A. Wisthaler, T. Mikoviny, J. Nowak, J. Peischl, J. M. Roberts, T. Ryerson, C. Warneke, and D. Helmig
Atmos. Chem. Phys., 15, 6721–6744, https://doi.org/10.5194/acp-15-6721-2015, https://doi.org/10.5194/acp-15-6721-2015, 2015
Short summary
Short summary
Eleven 3-D tropospheric chemistry models have been compared and evaluated with observations in the Arctic during the International Polar Year (IPY 2008). Large differences are seen among the models, particularly related to the model chemistry of volatile organic compounds (VOCs) and reactive nitrogen (NOx, PAN, HNO3) partitioning. Consistency among the models in the underestimation of CO, ethane and propane indicates the emission inventory is too low for these compounds.
S. R. Arnold, L. K. Emmons, S. A. Monks, K. S. Law, D. A. Ridley, S. Turquety, S. Tilmes, J. L. Thomas, I. Bouarar, J. Flemming, V. Huijnen, J. Mao, B. N. Duncan, S. Steenrod, Y. Yoshida, J. Langner, and Y. Long
Atmos. Chem. Phys., 15, 6047–6068, https://doi.org/10.5194/acp-15-6047-2015, https://doi.org/10.5194/acp-15-6047-2015, 2015
Short summary
Short summary
The extent to which forest fires produce the air pollutant and greenhouse gas ozone (O3) in the atmosphere at high latitudes in not well understood. We have compared how fire emissions produce O3 and its precursors in several models of atmospheric chemistry. We find enhancements in O3 in air dominated by fires in all models, which increase on average as fire emissions age. We also find that in situ O3 production in the Arctic is sensitive to details of organic chemistry and vertical lifting.
S. Tilmes, J.-F. Lamarque, L. K. Emmons, D. E. Kinnison, P.-L. Ma, X. Liu, S. Ghan, C. Bardeen, S. Arnold, M. Deeter, F. Vitt, T. Ryerson, J. W. Elkins, F. Moore, J. R. Spackman, and M. Val Martin
Geosci. Model Dev., 8, 1395–1426, https://doi.org/10.5194/gmd-8-1395-2015, https://doi.org/10.5194/gmd-8-1395-2015, 2015
Short summary
Short summary
The Community Atmosphere Model (CAM), version 5, is now coupled to extensive tropospheric and stratospheric chemistry, called CAM5-chem, and is available in addition to CAM4-chem in the Community Earth System Model (CESM) version 1.2. Both configurations are well suited as tools for atmospheric chemistry modeling studies in the troposphere and lower stratosphere.
S. A. Monks, S. R. Arnold, L. K. Emmons, K. S. Law, S. Turquety, B. N. Duncan, J. Flemming, V. Huijnen, S. Tilmes, J. Langner, J. Mao, Y. Long, J. L. Thomas, S. D. Steenrod, J. C. Raut, C. Wilson, M. P. Chipperfield, G. S. Diskin, A. Weinheimer, H. Schlager, and G. Ancellet
Atmos. Chem. Phys., 15, 3575–3603, https://doi.org/10.5194/acp-15-3575-2015, https://doi.org/10.5194/acp-15-3575-2015, 2015
Short summary
Short summary
Multi-model simulations of Arctic CO, O3 and OH are evaluated using observations. Models show highly variable concentrations but the relative importance of emission regions and types is robust across the models, demonstrating the importance of biomass burning as a source. Idealised tracer experiments suggest that some of the model spread is due to variations in simulated transport from Europe in winter and from Asia throughout the year.
F. Tummon, B. Hassler, N. R. P. Harris, J. Staehelin, W. Steinbrecht, J. Anderson, G. E. Bodeker, A. Bourassa, S. M. Davis, D. Degenstein, S. M. Frith, L. Froidevaux, E. Kyrölä, M. Laine, C. Long, A. A. Penckwitt, C. E. Sioris, K. H. Rosenlof, C. Roth, H.-J. Wang, and J. Wild
Atmos. Chem. Phys., 15, 3021–3043, https://doi.org/10.5194/acp-15-3021-2015, https://doi.org/10.5194/acp-15-3021-2015, 2015
Short summary
Short summary
Understanding ozone trends in the vertical is vital in terms of assessing the success of the Montreal Protocol. This paper compares and analyses the long-term trends in stratospheric ozone from seven new merged satellite data sets. The data sets largely agree well with each other, particularly for the negative trends seen in the early period 1984-1997. For the 1998-2011 period there is less agreement, but a clear shift from negative to mostly positive trends.
M. Val Martin, C. L. Heald, J.-F. Lamarque, S. Tilmes, L. K. Emmons, and B. A. Schichtel
Atmos. Chem. Phys., 15, 2805–2823, https://doi.org/10.5194/acp-15-2805-2015, https://doi.org/10.5194/acp-15-2805-2015, 2015
Short summary
Short summary
We present for the first time the relative effect of climate, emissions, and land use change on ozone and PM25 over the United States, focusing on the national parks. Air quality in 2050 will likely be dominated by emission patterns, but climate and land use changes alone can lead to a substantial increase in air pollution over most of the US, with important implications for O3 air quality, visibility and ecosystem health degradation in the national parks.
S. Tilmes, M. J. Mills, U. Niemeier, H. Schmidt, A. Robock, B. Kravitz, J.-F. Lamarque, G. Pitari, and J. M. English
Geosci. Model Dev., 8, 43–49, https://doi.org/10.5194/gmd-8-43-2015, https://doi.org/10.5194/gmd-8-43-2015, 2015
Short summary
Short summary
A new Geoengineering Model Intercomparison Project (GeoMIP) experiment “G4 specified stratospheric aerosols” (G4SSA) is proposed to investigate the impact of stratospheric aerosol geoengineering on atmosphere, chemistry, dynamics, climate, and the environment. In contrast to the earlier G4 GeoMIP experiment, which requires an emission of sulfur dioxide (SO2) into the model, a prescribed aerosol forcing file is provided to the community, to be consistently applied to future model experiments.
A. Saiz-Lopez, R. P. Fernandez, C. Ordóñez, D. E. Kinnison, J. C. Gómez Martín, J.-F. Lamarque, and S. Tilmes
Atmos. Chem. Phys., 14, 13119–13143, https://doi.org/10.5194/acp-14-13119-2014, https://doi.org/10.5194/acp-14-13119-2014, 2014
K. Tsigaridis, N. Daskalakis, M. Kanakidou, P. J. Adams, P. Artaxo, R. Bahadur, Y. Balkanski, S. E. Bauer, N. Bellouin, A. Benedetti, T. Bergman, T. K. Berntsen, J. P. Beukes, H. Bian, K. S. Carslaw, M. Chin, G. Curci, T. Diehl, R. C. Easter, S. J. Ghan, S. L. Gong, A. Hodzic, C. R. Hoyle, T. Iversen, S. Jathar, J. L. Jimenez, J. W. Kaiser, A. Kirkevåg, D. Koch, H. Kokkola, Y. H Lee, G. Lin, X. Liu, G. Luo, X. Ma, G. W. Mann, N. Mihalopoulos, J.-J. Morcrette, J.-F. Müller, G. Myhre, S. Myriokefalitakis, N. L. Ng, D. O'Donnell, J. E. Penner, L. Pozzoli, K. J. Pringle, L. M. Russell, M. Schulz, J. Sciare, Ø. Seland, D. T. Shindell, S. Sillman, R. B. Skeie, D. Spracklen, T. Stavrakou, S. D. Steenrod, T. Takemura, P. Tiitta, S. Tilmes, H. Tost, T. van Noije, P. G. van Zyl, K. von Salzen, F. Yu, Z. Wang, Z. Wang, R. A. Zaveri, H. Zhang, K. Zhang, Q. Zhang, and X. Zhang
Atmos. Chem. Phys., 14, 10845–10895, https://doi.org/10.5194/acp-14-10845-2014, https://doi.org/10.5194/acp-14-10845-2014, 2014
D. W. Fahey, R.-S. Gao, O. Möhler, H. Saathoff, C. Schiller, V. Ebert, M. Krämer, T. Peter, N. Amarouche, L. M. Avallone, R. Bauer, Z. Bozóki, L. E. Christensen, S. M. Davis, G. Durry, C. Dyroff, R. L. Herman, S. Hunsmann, S. M. Khaykin, P. Mackrodt, J. Meyer, J. B. Smith, N. Spelten, R. F. Troy, H. Vömel, S. Wagner, and F. G. Wienhold
Atmos. Meas. Tech., 7, 3177–3213, https://doi.org/10.5194/amt-7-3177-2014, https://doi.org/10.5194/amt-7-3177-2014, 2014
A. Khodayari, S. Tilmes, S. C. Olsen, D. B. Phoenix, D. J. Wuebbles, J.-F. Lamarque, and C.-C. Chen
Atmos. Chem. Phys., 14, 9925–9939, https://doi.org/10.5194/acp-14-9925-2014, https://doi.org/10.5194/acp-14-9925-2014, 2014
K. Sindelarova, C. Granier, I. Bouarar, A. Guenther, S. Tilmes, T. Stavrakou, J.-F. Müller, U. Kuhn, P. Stefani, and W. Knorr
Atmos. Chem. Phys., 14, 9317–9341, https://doi.org/10.5194/acp-14-9317-2014, https://doi.org/10.5194/acp-14-9317-2014, 2014
A. R. Berg, C. L. Heald, K. E. Huff Hartz, A. G. Hallar, A. J. H. Meddens, J. A. Hicke, J.-F. Lamarque, and S. Tilmes
Atmos. Chem. Phys., 13, 3149–3161, https://doi.org/10.5194/acp-13-3149-2013, https://doi.org/10.5194/acp-13-3149-2013, 2013
P. J. Young, A. T. Archibald, K. W. Bowman, J.-F. Lamarque, V. Naik, D. S. Stevenson, S. Tilmes, A. Voulgarakis, O. Wild, D. Bergmann, P. Cameron-Smith, I. Cionni, W. J. Collins, S. B. Dalsøren, R. M. Doherty, V. Eyring, G. Faluvegi, L. W. Horowitz, B. Josse, Y. H. Lee, I. A. MacKenzie, T. Nagashima, D. A. Plummer, M. Righi, S. T. Rumbold, R. B. Skeie, D. T. Shindell, S. A. Strode, K. Sudo, S. Szopa, and G. Zeng
Atmos. Chem. Phys., 13, 2063–2090, https://doi.org/10.5194/acp-13-2063-2013, https://doi.org/10.5194/acp-13-2063-2013, 2013
L. C. Paulik and T. Birner
Atmos. Chem. Phys., 12, 12183–12195, https://doi.org/10.5194/acp-12-12183-2012, https://doi.org/10.5194/acp-12-12183-2012, 2012
Related subject area
Subject: Dynamics | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Synoptic and microphysical lifetime constraints for contrails
Country- and species-dependent parameters for the heating degree day method to distribute NOx and PM emissions from residential heating in the EU 27: application to air quality modelling and multi-year emission projections
Physical processes influencing the Asian climate due to black carbon emission over East and South Asia
Valley floor inclination affecting valley winds and transport of passive tracers in idealised simulations
To what extent is the description of streets important in estimating local air quality: a case study over Paris
Variability and trends in the potential vorticity (PV)-gradient dynamical tropopause
Kinematic properties of regions that can involve persistent contrails
The spatiotemporal evolution of atmospheric boundary layers over a thermally heterogeneous landscape
The marinada fall wind in the eastern Ebro sub-basin: physical mechanisms and role of the sea, orography and irrigation
The influences of El Niño–Southern Oscillation on tropospheric ozone in CMIP6 models
Technical note: Exploring parameter and meteorological uncertainty via emulation in volcanic ash atmospheric dispersion modelling
Role of the Indian Ocean basin mode in driving the interdecadal variations of summer precipitation over the East Asian monsoon boundary zone
Extreme ozone episodes in a major Mediterranean urban area
Wintertime extreme warming events in the high Arctic: characteristics, drivers, trends, and the role of atmospheric rivers
Influence of lower-tropospheric moisture on local soil moisture–precipitation feedback over the US Southern Great Plains
The Lagrangian Atmospheric Radionuclide Transport Model (ARTM) – sensitivity studies and evaluation using airborne measurements of power plant emissions
Large-eddy-model closure and simulation of turbulent flux patterns over oasis surface
Impact of the Guinea coast upwelling on atmospheric dynamics, precipitation and pollutant transport over southern West Africa
Investigating multiscale meteorological controls and impact of soil moisture heterogeneity on radiation fog in complex terrain using semi-idealised simulations
Effect of the boundary layer low-level jet on fast fog spatial propagation
Mediterranean tropical-like cyclone forecasts and analysis using the ECMWF ensemble forecasting system with physical parameterization perturbations
Using synthetic case studies to explore the spread and calibration of ensemble atmospheric dispersion forecasts
Meteorological modeling sensitivity to parameterizations and satellite-derived surface datasets during the 2017 Lake Michigan Ozone Study
Trajectory enhancement of low-earth orbiter thermodynamic retrievals to predict convection: a simulation experiment
Lagrangian transport simulations using the extreme convection parameterization: an assessment for the ECMWF reanalyses
Better-constrained climate sensitivity when accounting for dataset dependency on pattern effect estimates
Determination of the chemical equator from GEOS-Chem model simulation: a focus on the tropical western Pacific region
Uncertainty in parameterized convection remains a key obstacle for estimating surface fluxes of carbon dioxide
Antarctic atmospheric Richardson number from radiosonde measurements and AMPS
Divergent convective outflow in large-eddy simulations
Modulation of daily PM2.5 concentrations over China in winter by large-scale circulation and climate change
Modeling of street-scale pollutant dispersion by coupled simulation of chemical reaction, aerosol dynamics, and CFD
Daytime along-valley winds in the Himalayas as simulated by the Weather Research and Forecasting (WRF) model
Evolution of squall line variability and error growth in an ensemble of large eddy simulations
Climatology and variability of air mass transport from the boundary layer to the Asian monsoon anticyclone
Evaluation and bias correction of probabilistic volcanic ash forecasts
The representation of the trade winds in ECMWF forecasts and reanalyses during EUREC4A
Modeling approaches for atmospheric ion–dipole collisions: all-atom trajectory simulations and central field methods
Parameterizing the aerodynamic effect of trees in street canyons for the street network model MUNICH using the CFD model Code_Saturne
Quantifying the impact of meteorological uncertainty on emission estimates and the risk to aviation using source inversion for the Raikoke 2019 eruption
Acceleration of the southern African easterly jet driven by the radiative effect of biomass burning aerosols and its impact on transport during AEROCLO-sA
The Sun's role in decadal climate predictability in the North Atlantic
Future projections of daily haze-conducive and clear weather conditions over the North China Plain using a perturbed parameter ensemble
Refining an ensemble of volcanic ash forecasts using satellite retrievals: Raikoke 2019
Ship-based estimates of momentum transfer coefficient over sea ice and recommendations for its parameterization
Revising the definition of anthropogenic heat flux from buildings: role of human activities and building storage heat flux
An assessment of tropopause characteristics of the ERA5 and ERA-Interim meteorological reanalyses
Distinct evolutions of haze pollution from winter to the following spring over the North China Plain: role of the North Atlantic sea surface temperature anomalies
The foehn effect during easterly flow over Svalbard
Effect of rainfall-induced diabatic heating over southern China on the formation of wintertime haze on the North China Plain
Sina Maria Hofer and Klaus Martin Gierens
EGUsphere, https://doi.org/10.5194/egusphere-2025-326, https://doi.org/10.5194/egusphere-2025-326, 2025
Short summary
Short summary
The climate effect of contrails depends on contrail lifetime. Thus, it is important to know what constrains the lifetime. In this paper we characterize the two most important contrail dissolution processes via their respective time-scales. Both time-scales are in the order of a couple of hours, depending on the synoptic situation and the size of the contrail ice crystals. The combined time-scale which combines both processes is the harmonic mean of the two single time-scales.
Antoine Guion, Florian Couvidat, Marc Guevara, and Augustin Colette
Atmos. Chem. Phys., 25, 2807–2827, https://doi.org/10.5194/acp-25-2807-2025, https://doi.org/10.5194/acp-25-2807-2025, 2025
Short summary
Short summary
The residential sector can cause high background levels of pollutants and pollution peaks in winter. Its emissions are dominated by space heating and show strong daily variations linked to changes in outside temperature. Using heating degree days, we provide country- and species-dependent parameters for the distribution of these emissions, improving the performance of the CHIMERE air quality model. This also allows annual residential emissions to be projected before official publications.
Feifei Luo, Bjørn Samset, Camilla Stjern, Manoj Joshi, Laura Wilcox, Robert Allen, Wei Hua, and Shuanglin Li
EGUsphere, https://doi.org/10.5194/egusphere-2024-3867, https://doi.org/10.5194/egusphere-2024-3867, 2025
Short summary
Short summary
Black carbon (BC) aerosol is emitted from the incomplete combustion of biomass and fossil fuels. We found that Asian BC lead to a strong local cooling and drying. Reductions in precipitation primarily depend on the thermodynamic effects due to solar radiation absorption by BC. The combined thermodynamic and Dynamic effects shape the spatial pattern of precipitation responses to Asian BC. These results help further understand the impact of emissions of anthropogenic aerosols on Asian climate.
Johannes Mikkola, Alexander Gohm, Victoria A. Sinclair, and Federico Bianchi
Atmos. Chem. Phys., 25, 511–533, https://doi.org/10.5194/acp-25-511-2025, https://doi.org/10.5194/acp-25-511-2025, 2025
Short summary
Short summary
This study investigates the influence of valley floor inclination on diurnal winds and passive tracer transport within idealised mountain valleys using numerical simulations. The valley inclination strengthens the daytime up-valley winds but only up to a certain point. Beyond that critical angle, the winds weaken again. The inclined valleys transport the tracers higher up in the free troposphere, which would, for example, lead to higher potential for long-range transport.
Alexis Squarcioni, Yelva Roustan, Myrto Valari, Youngseob Kim, Karine Sartelet, Lya Lugon, Fabrice Dugay, and Robin Voitot
Atmos. Chem. Phys., 25, 93–117, https://doi.org/10.5194/acp-25-93-2025, https://doi.org/10.5194/acp-25-93-2025, 2025
Short summary
Short summary
This study highlights the interest of using a street-network model to estimate pollutant concentrations of NOx, NO2, and PM2.5 in heterogeneous urban areas, particularly those adjacent to highways, compared with the subgrid-scale approach embedded in the 3D Eulerian model CHIMERE. However, the study also reveals comparable performances between the two approaches for the aforementioned pollutants in areas near the city center, where urban characteristics are more uniform.
Katharina Turhal, Felix Plöger, Jan Clemens, Thomas Birner, Franziska Weyland, Paul Konopka, and Peter Hoor
Atmos. Chem. Phys., 24, 13653–13679, https://doi.org/10.5194/acp-24-13653-2024, https://doi.org/10.5194/acp-24-13653-2024, 2024
Short summary
Short summary
The tropopause separates the troposphere, where many greenhouse gases originate, from the stratosphere. This study examines a tropopause defined by potential vorticity – an analogue for angular momentum that changes sharply in the subtropics, creating a transport barrier. Between 1980 and 2017, this tropopause shifted poleward at lower altitudes and equatorward above, suggesting height-dependent changes in atmospheric circulation that may affect greenhouse gas distribution and global warming.
Sina Maria Hofer and Klaus Martin Gierens
EGUsphere, https://doi.org/10.5194/egusphere-2024-3520, https://doi.org/10.5194/egusphere-2024-3520, 2024
Short summary
Short summary
Ice supersaturation is an immaterial feature, which does not generally move with the wind that carries contrails and cirrus clouds. Here we analyse the different motions and show that ice supersaturated regions (ISSRs) on average move slower than the wind, the direction of movement is usually quite similar and the distributions of both velocities follow Weibull distributions. The almost identical direction of the movements is beneficial for contrail lifetimes.
Mary Rose Mangan, Jordi Vilà-Guerau de Arellano, Bart J. H. van Stratum, Marie Lothon, Guylaine Canut-Rocafort, and Oscar K. Hartogensis
EGUsphere, https://doi.org/10.5194/egusphere-2024-3000, https://doi.org/10.5194/egusphere-2024-3000, 2024
Short summary
Short summary
Using observations and high-resolution turbulence modeling, we examine the influence of irrigation-driven surface heterogeneity on the atmospheric boundary layer (ABL). We employ different spatial scales of heterogeneity to explore how the influence of surface heterogeneity on the ABL within a single grid cell would change in higher resolution global models. We find that the height of the ABL is highly variable, and that the surface heterogeneity is felt least strongly in the middle of the ABL.
Tanguy Lunel, Maria Antonia Jimenez, Joan Cuxart, Daniel Martinez-Villagrasa, Aaron Boone, and Patrick Le Moigne
Atmos. Chem. Phys., 24, 7637–7666, https://doi.org/10.5194/acp-24-7637-2024, https://doi.org/10.5194/acp-24-7637-2024, 2024
Short summary
Short summary
During the summer in Catalonia, a cool wind, the marinada, blows into the eastern Ebro basin in the afternoon. This study investigates its previously unclear dynamics using observations and a meteorological model. It is found to be driven by a cool marine air mass that flows over the mountains into the basin. The study shows how the sea breeze, upslope winds, larger weather patterns and irrigation play a prominent role in the formation and characteristics of the marinada.
Thanh Le, Seon-Ho Kim, Jae-Yeong Heo, and Deg-Hyo Bae
Atmos. Chem. Phys., 24, 6555–6566, https://doi.org/10.5194/acp-24-6555-2024, https://doi.org/10.5194/acp-24-6555-2024, 2024
Short summary
Short summary
We examined the links between the El Niño–Southern Oscillation (ENSO) and tropospheric ozone (O3) using model data. Our results show that ENSO impacts on tropospheric O3 are mainly found over oceans, while the signature of ENSO over continents is largely unclear. These impacts in the midlatitude regions over the Southern Hemisphere may be more significant than previously known. The responses of O3 to ENSO are weak in the middle troposphere and stronger in the upper and lower troposphere.
James M. Salter, Helen N. Webster, and Cameron Saint
Atmos. Chem. Phys., 24, 6251–6274, https://doi.org/10.5194/acp-24-6251-2024, https://doi.org/10.5194/acp-24-6251-2024, 2024
Short summary
Short summary
Models are used to make forecasts of volcanic ash dispersion during eruptions. These models have unknown inputs relating to the eruption itself, physical processes, and meteorological conditions. We use statistical models to predict the output of the expensive physical model and show we can account for the effects of the different inputs. We compare the model to real-world observations and show that accounting for all sources of uncertainty may lead to different conclusions about the inputs.
Jing Wang, Yanju Liu, Fei Cheng, Chengyu Song, Qiaoping Li, Yihui Ding, and Xiangde Xu
Atmos. Chem. Phys., 24, 5099–5115, https://doi.org/10.5194/acp-24-5099-2024, https://doi.org/10.5194/acp-24-5099-2024, 2024
Short summary
Short summary
Based on long-term observational, reanalysis, and numerical model simulation datasets from 1901 through 2014, this study shows that precipitation over the East Asian monsoon boundary zone featured prominent interdecadal changes, with dry summers during the periods preceding 1927, 1939–1945, 1968–1982, and 1998–2010 and wet summers during 1928–1938, 1946–1967, and 2011 onwards. The Indian Ocean basin mode is an important oceanic modulator responsible for its interdecadal variations.
Jordi Massagué, Eduardo Torre-Pascual, Cristina Carnerero, Miguel Escudero, Andrés Alastuey, Marco Pandolfi, Xavier Querol, and Gotzon Gangoiti
Atmos. Chem. Phys., 24, 4827–4850, https://doi.org/10.5194/acp-24-4827-2024, https://doi.org/10.5194/acp-24-4827-2024, 2024
Short summary
Short summary
This study analyses three acute ozone episodes in Barcelona (NE Spain) which have occurred only in recent years and are of particular concern due to the city's significant population. The findings uncover a complex interplay of factors, notably shared among episodes, including pollution transport at different scales and specific weather and emission patterns. These insights significantly enhance our understanding of these occurrences and improve predictive capabilities.
Weiming Ma, Hailong Wang, Gang Chen, Yun Qian, Ian Baxter, Yiling Huo, and Mark W. Seefeldt
Atmos. Chem. Phys., 24, 4451–4472, https://doi.org/10.5194/acp-24-4451-2024, https://doi.org/10.5194/acp-24-4451-2024, 2024
Short summary
Short summary
Extreme warming events with surface temperature going above 0°C can occur in the high-Arctic winter. Although reanalysis data show that these events were short-lived and occurred rarely during 1980–2021, they have become more frequent, stronger, and longer lasting latterly. A dipole pattern, comprising high- and low-pressure systems, is found to be the key in driving them. These findings have implications for the recent changes in sea ice, hydrological cycle, and ecosystem over the Arctic.
Gaoyun Wang, Rong Fu, Yizhou Zhuang, Paul A. Dirmeyer, Joseph A. Santanello, Guiling Wang, Kun Yang, and Kaighin McColl
Atmos. Chem. Phys., 24, 3857–3868, https://doi.org/10.5194/acp-24-3857-2024, https://doi.org/10.5194/acp-24-3857-2024, 2024
Short summary
Short summary
This study investigates the influence of lower-tropospheric humidity on land–atmosphere coupling (LAC) during warm seasons in the US Southern Great Plains. Using radiosonde data and a buoyancy model, we find that elevated LT humidity is crucial for generating afternoon precipitation events under dry soil conditions not accounted for by conventional LAC indices. This underscores the importance of considering LT humidity in understanding LAC over dry soil during droughts in the SGP.
Robert Hanfland, Dominik Brunner, Christiane Voigt, Alina Fiehn, Anke Roiger, and Margit Pattantyús-Ábrahám
Atmos. Chem. Phys., 24, 2511–2534, https://doi.org/10.5194/acp-24-2511-2024, https://doi.org/10.5194/acp-24-2511-2024, 2024
Short summary
Short summary
To show that the three-dimensional dispersion of plumes simulated by the Atmospheric Radionuclide Transport Model within the planetary boundary layer agrees with real plumes, we identify the most important input parameters and analyse the turbulence properties of five different turbulence models in very unstable stratification conditions using their deviation from the well-mixed state. Simulations show that one model agrees slightly better in unstable stratification conditions.
Bangjun Cao, Yaping Shao, Xianyu Yang, Xin Yin, and Shaofeng Liu
Atmos. Chem. Phys., 24, 275–285, https://doi.org/10.5194/acp-24-275-2024, https://doi.org/10.5194/acp-24-275-2024, 2024
Short summary
Short summary
Our novel scheme enhances large-eddy simulations (LESs) for atmosphere–land interactions. It couples LES subgrid closure with Monin–Obukhov similarity theory (MOST), overcoming MOST's limitations. Validated over diverse land surfaces, our approach outperforms existing methods, aligning well with field measurements. Robustness is demonstrated across varying model resolutions. MOST's influence strengthens with decreasing grid spacing, particularly for sensible heat flux.
Gaëlle de Coëtlogon, Adrien Deroubaix, Cyrille Flamant, Laurent Menut, and Marco Gaetani
Atmos. Chem. Phys., 23, 15507–15521, https://doi.org/10.5194/acp-23-15507-2023, https://doi.org/10.5194/acp-23-15507-2023, 2023
Short summary
Short summary
Using a numerical atmospheric model, we found that cooling sea surface temperatures along the southern coast of West Africa in July cause the “little dry season”. This effect reduces humidity and pollutant transport inland, potentially enhancing West Africa's synoptic and seasonal forecasting.
Dongqi Lin, Marwan Katurji, Laura E. Revell, Basit Khan, and Andrew Sturman
Atmos. Chem. Phys., 23, 14451–14479, https://doi.org/10.5194/acp-23-14451-2023, https://doi.org/10.5194/acp-23-14451-2023, 2023
Short summary
Short summary
Accurate fog forecasting is difficult in a complex environment. Spatial variations in soil moisture could impact fog. Here, we carried out fog simulations with spatially different soil moisture in complex topography. The soil moisture was calculated using satellite observations. The results show that the spatial variations in soil moisture do not have a significant impact on where fog occurs but do impact how long fog lasts. This finding could improve fog forecasts in the future.
Shuqi Yan, Hongbin Wang, Xiaohui Liu, Fan Zu, and Duanyang Liu
Atmos. Chem. Phys., 23, 13987–14002, https://doi.org/10.5194/acp-23-13987-2023, https://doi.org/10.5194/acp-23-13987-2023, 2023
Short summary
Short summary
In this study, we quantitatively study the effect of the boundary layer low-level jet (BLLJ) on fast fog spatial propagation; i.e., the fog area expands very fast along a certain direction. The wind speed (10 m s−1) and direction (southeast) of the BLLJ core are consistent with fog propagation (9.6 m s−1). The BLLJ-induced temperature and moisture advections are possible reasons for fast fog propagation. The propagation speed would decrease by 6.4 m s−1 if these advections were turned off.
Miriam Saraceni, Lorenzo Silvestri, Peter Bechtold, and Paolina Bongioannini Cerlini
Atmos. Chem. Phys., 23, 13883–13909, https://doi.org/10.5194/acp-23-13883-2023, https://doi.org/10.5194/acp-23-13883-2023, 2023
Short summary
Short summary
This study focuses on three medicanes, tropical-like cyclones that form in the Mediterranean Sea, studied by ensemble forecasting. This involved multiple simulations of the same event by varying initial conditions and model physics parameters, especially related to convection, which showed comparable results. It is found that medicane development is influenced by the model's ability to predict precursor events and the interaction between upper and lower atmosphere dynamics and thermodynamics.
Andrew R. Jones, Susan J. Leadbetter, and Matthew C. Hort
Atmos. Chem. Phys., 23, 12477–12503, https://doi.org/10.5194/acp-23-12477-2023, https://doi.org/10.5194/acp-23-12477-2023, 2023
Short summary
Short summary
The paper explores spread and calibration properties of ensemble atmospheric dispersion forecasts for hypothetical release events. Real-time forecasts from an ensemble weather prediction system were used to generate an ensemble of dispersion predictions and assessed against simulations produced using analysis meteorology. Results demonstrate good performance overall but highlight more skilful predictions for material released in the upper air compared with releases near the surface.
Jason A. Otkin, Lee M. Cronce, Jonathan L. Case, R. Bradley Pierce, Monica Harkey, Allen Lenzen, David S. Henderson, Zac Adelman, Tsengel Nergui, and Christopher R. Hain
Atmos. Chem. Phys., 23, 7935–7954, https://doi.org/10.5194/acp-23-7935-2023, https://doi.org/10.5194/acp-23-7935-2023, 2023
Short summary
Short summary
We performed model simulations to assess the impact of different parameterization schemes, surface initialization datasets, and analysis nudging on lower-tropospheric conditions near Lake Michigan. Simulations were run with high-resolution, real-time datasets depicting lake surface temperatures, green vegetation fraction, and soil moisture. The most accurate results were obtained when using high-resolution sea surface temperature and soil datasets to constrain the model simulations.
Mark T. Richardson, Brian H. Kahn, and Peter Kalmus
Atmos. Chem. Phys., 23, 7699–7717, https://doi.org/10.5194/acp-23-7699-2023, https://doi.org/10.5194/acp-23-7699-2023, 2023
Short summary
Short summary
Convection over land often triggers hours after a satellite last passed overhead and measured the state of the atmosphere, and during those hours the atmosphere can change greatly. Here we show that it is possible to reconstruct most of those changes by using weather forecast winds to predict where warm and moist air parcels will travel. The results can be used to better predict where precipitation is likely to happen in the hours after satellite measurements.
Lars Hoffmann, Paul Konopka, Jan Clemens, and Bärbel Vogel
Atmos. Chem. Phys., 23, 7589–7609, https://doi.org/10.5194/acp-23-7589-2023, https://doi.org/10.5194/acp-23-7589-2023, 2023
Short summary
Short summary
Atmospheric convection plays a key role in tracer transport in the troposphere. Global meteorological forecasts and reanalyses typically have a coarse spatiotemporal resolution that does not adequately resolve the dynamics, transport, and mixing of air associated with storm systems or deep convection. We discuss the application of the extreme convection parameterization in a Lagrangian transport model to improve simulations of tracer transport from the boundary layer into the free troposphere.
Angshuman Modak and Thorsten Mauritsen
Atmos. Chem. Phys., 23, 7535–7549, https://doi.org/10.5194/acp-23-7535-2023, https://doi.org/10.5194/acp-23-7535-2023, 2023
Short summary
Short summary
We provide an improved estimate of equilibrium climate sensitivity (ECS) constrained based on the instrumental temperature record including the corrections for the pattern effect. The improved estimate factors in the uncertainty caused by the underlying sea-surface temperature datasets used in the estimates of pattern effect. This together with the inter-model spread lifts the corresponding IPCC AR6 estimate to 3.2 K [1.8 to 11.0], which is lower and better constrained than in past studies.
Xiaoyu Sun, Mathias Palm, Katrin Müller, Jonas Hachmeister, and Justus Notholt
Atmos. Chem. Phys., 23, 7075–7090, https://doi.org/10.5194/acp-23-7075-2023, https://doi.org/10.5194/acp-23-7075-2023, 2023
Short summary
Short summary
The tropical western Pacific (TWP) is an active interhemispheric transport region contributing significantly to the global climate. A method to determine the chemical equator was developed by model simulations of a virtual passive tracer to analyze transport in the tropics, with a focus on the TWP region. We compare the chemical equator with tropical rain belts and wind fields and obtain a vertical pattern of interhemispheric transport processes which shows tilt structure in certain seasons.
Andrew E. Schuh and Andrew R. Jacobson
Atmos. Chem. Phys., 23, 6285–6297, https://doi.org/10.5194/acp-23-6285-2023, https://doi.org/10.5194/acp-23-6285-2023, 2023
Short summary
Short summary
A comparison of atmospheric carbon dioxide concentrations resulting from two different atmospheric transport models showed large differences in predicted concentrations with significant space–time correlations. The vertical mixing of long-lived trace gases by convection was determined to be the main driver of these differences. The resulting uncertainty was deemed significant to the application of using atmospheric gradients of carbon dioxide to estimate surface fluxes of carbon dioxide.
Qike Yang, Xiaoqing Wu, Xiaodan Hu, Zhiyuan Wang, Chun Qing, Tao Luo, Pengfei Wu, Xianmei Qian, and Yiming Guo
Atmos. Chem. Phys., 23, 6339–6355, https://doi.org/10.5194/acp-23-6339-2023, https://doi.org/10.5194/acp-23-6339-2023, 2023
Short summary
Short summary
The AMPS-forecasted Richardson number was first comprehensively validated over the Antarctic continent. Some potential underlying reasons for the discrepancies between the forecasts and observations were analyzed. The underlying physical processes of triggering atmospheric turbulence in Antarctica were investigated. Our results suggest that the estimated Richardson number by the AMPS is reasonable and the turbulence conditions in Antarctica are well revealed.
Edward Groot and Holger Tost
Atmos. Chem. Phys., 23, 6065–6081, https://doi.org/10.5194/acp-23-6065-2023, https://doi.org/10.5194/acp-23-6065-2023, 2023
Short summary
Short summary
It is shown that the outflow from cumulonimbus clouds or thunderstorms in the upper troposphere and lower stratosphere in idealized high-resolution simulations (LESs) depends linearly on the net amount of latent heat released by the cloud for fixed geometry of the clouds. However, it is shown that, in more realistic situations, convective organization and aggregation (collecting mechanisms of cumulonimbus clouds) affect the amount of outflow non-linearly through non-idealized geometry.
Zixuan Jia, Carlos Ordóñez, Ruth M. Doherty, Oliver Wild, Steven T. Turnock, and Fiona M. O'Connor
Atmos. Chem. Phys., 23, 2829–2842, https://doi.org/10.5194/acp-23-2829-2023, https://doi.org/10.5194/acp-23-2829-2023, 2023
Short summary
Short summary
This study investigates the influence of the winter large-scale circulation on daily concentrations of PM2.5 and their sensitivity to emissions. The new proposed circulation index can effectively distinguish different levels of air pollution and explain changes in PM2.5 sensitivity to emissions from local and surrounding regions. We then project future changes in PM2.5 concentrations using this index and find an increase in PM2.5 concentrations over the region due to climate change.
Chao Lin, Yunyi Wang, Ryozo Ooka, Cédric Flageul, Youngseob Kim, Hideki Kikumoto, Zhizhao Wang, and Karine Sartelet
Atmos. Chem. Phys., 23, 1421–1436, https://doi.org/10.5194/acp-23-1421-2023, https://doi.org/10.5194/acp-23-1421-2023, 2023
Short summary
Short summary
In this study, SSH-aerosol, a modular box model that simulates the evolution of gas, primary, and secondary aerosols, is coupled with the computational fluid dynamics (CFD) software, OpenFOAM and Code_Saturne. The transient dispersion of pollutants emitted from traffic in a street canyon of Greater Paris is simulated. The coupled model achieved better agreement in NO2 and PM10 with measurement data than the conventional CFD simulation which regards pollutants as passive scalars.
Johannes Mikkola, Victoria A. Sinclair, Marja Bister, and Federico Bianchi
Atmos. Chem. Phys., 23, 821–842, https://doi.org/10.5194/acp-23-821-2023, https://doi.org/10.5194/acp-23-821-2023, 2023
Short summary
Short summary
Local winds in four valleys located in the Nepal Himalayas are studied by means of high-resolution meteorological modelling. Well-defined daytime up-valley winds are simulated in all of the valleys with some variation in the flow depth and strength among the valleys and their parts. Parts of the valleys with a steep valley floor inclination (2–5°) are associated with weaker and shallower daytime up-valley winds compared with the parts that have nearly flat valley floors (< 1°).
Edward Groot and Holger Tost
Atmos. Chem. Phys., 23, 565–585, https://doi.org/10.5194/acp-23-565-2023, https://doi.org/10.5194/acp-23-565-2023, 2023
Short summary
Short summary
Thunderstorm systems play an important role in the dynamics of the Earth’s atmosphere, and some of them form a well-organised line: squall lines. Simulations of such squall lines with very small initial perturbations are compared to a reference simulation. The evolution of perturbations and processes amplifying them are analysed. It is shown that the formation of new secondary thunderstorm cells (after the initial primary cells) directly ahead of the line affects the spread strongly.
Matthias Nützel, Sabine Brinkop, Martin Dameris, Hella Garny, Patrick Jöckel, Laura L. Pan, and Mijeong Park
Atmos. Chem. Phys., 22, 15659–15683, https://doi.org/10.5194/acp-22-15659-2022, https://doi.org/10.5194/acp-22-15659-2022, 2022
Short summary
Short summary
During the Asian summer monsoon season, a large high-pressure system is present at levels close to the tropopause above Asia. We analyse how air masses are transported from surface levels to this high-pressure system, which shows distinct features from the surrounding air masses. To this end, we employ multiannual data from two complementary models that allow us to analyse the climatology as well as the interannual and intraseasonal variability of these transport pathways.
Alice Crawford, Tianfeng Chai, Binyu Wang, Allison Ring, Barbara Stunder, Christopher P. Loughner, Michael Pavolonis, and Justin Sieglaff
Atmos. Chem. Phys., 22, 13967–13996, https://doi.org/10.5194/acp-22-13967-2022, https://doi.org/10.5194/acp-22-13967-2022, 2022
Short summary
Short summary
This study describes the development of a workflow which produces probabilistic and quantitative forecasts of volcanic ash in the atmosphere. The workflow includes methods of incorporating satellite observations of the ash cloud into a modeling framework as well as verification statistics that can be used to guide further model development and provide information for risk-based approaches to flight planning.
Alessandro Carlo Maria Savazzi, Louise Nuijens, Irina Sandu, Geet George, and Peter Bechtold
Atmos. Chem. Phys., 22, 13049–13066, https://doi.org/10.5194/acp-22-13049-2022, https://doi.org/10.5194/acp-22-13049-2022, 2022
Short summary
Short summary
Winds are of great importance for the transport of energy and moisture in the atmosphere. In this study we use measurements from the EUREC4A field campaign and several model experiments to understand the wind bias in the forecasts produced by the European Centre for Medium-Range Weather Forecasts. We are able to link the model errors to heights above 2 km and to the representation of the diurnal cycle of winds: the model makes the winds too slow in the morning and too strong in the evening.
Ivo Neefjes, Roope Halonen, Hanna Vehkamäki, and Bernhard Reischl
Atmos. Chem. Phys., 22, 11155–11172, https://doi.org/10.5194/acp-22-11155-2022, https://doi.org/10.5194/acp-22-11155-2022, 2022
Short summary
Short summary
Collisions between ionic and dipolar molecules and clusters facilitate the formation of atmospheric aerosol particles, which affect global climate and air quality. We compared often-used classical approaches for calculating ion–dipole collision rates with robust atomistic computer simulations. While classical approaches work for simple ions and dipoles only, our modeling approach can also efficiently calculate reasonable collision properties for more complex systems.
Alice Maison, Cédric Flageul, Bertrand Carissimo, Yunyi Wang, Andrée Tuzet, and Karine Sartelet
Atmos. Chem. Phys., 22, 9369–9388, https://doi.org/10.5194/acp-22-9369-2022, https://doi.org/10.5194/acp-22-9369-2022, 2022
Short summary
Short summary
This paper presents a parameterization of the tree crown effect on air flow and pollutant dispersion in a street network model used to simulate air quality at the street level. The new parameterization is built using a finer-scale model (computational fluid dynamics). The tree effect increases with the leaf area index and the crown volume fraction of the trees; the street horizontal velocity is reduced by up to 68 % and the vertical transfer into or out of the street by up to 23 %.
Natalie J. Harvey, Helen F. Dacre, Cameron Saint, Andrew T. Prata, Helen N. Webster, and Roy G. Grainger
Atmos. Chem. Phys., 22, 8529–8545, https://doi.org/10.5194/acp-22-8529-2022, https://doi.org/10.5194/acp-22-8529-2022, 2022
Short summary
Short summary
In the event of a volcanic eruption, airlines need to make decisions about which routes are safe to operate and ensure that airborne aircraft land safely. The aim of this paper is to demonstrate the application of a statistical technique that best combines ash information from satellites and a suite of computer forecasts of ash concentration to provide a range of plausible estimates of how much volcanic ash emitted from a volcano is available to undergo long-range transport.
Jean-Pierre Chaboureau, Laurent Labbouz, Cyrille Flamant, and Alma Hodzic
Atmos. Chem. Phys., 22, 8639–8658, https://doi.org/10.5194/acp-22-8639-2022, https://doi.org/10.5194/acp-22-8639-2022, 2022
Short summary
Short summary
Ground-based, spaceborne and rare airborne observations of biomass burning aerosols (BBAs) during the AEROCLO-sA field campaign in 2017 are complemented with convection-permitting simulations with online trajectories. The results show that the radiative effect of the BBA accelerates the southern African easterly jet and generates upward motions that transport the BBAs to higher altitudes and farther southwest.
Annika Drews, Wenjuan Huo, Katja Matthes, Kunihiko Kodera, and Tim Kruschke
Atmos. Chem. Phys., 22, 7893–7904, https://doi.org/10.5194/acp-22-7893-2022, https://doi.org/10.5194/acp-22-7893-2022, 2022
Short summary
Short summary
Solar irradiance varies with a period of approximately 11 years. Using a unique large chemistry–climate model dataset, we investigate the solar surface signal in the North Atlantic and European region and find that it changes over time, depending on the strength of the solar cycle. For the first time, we estimate the potential predictability associated with including realistic solar forcing in a model. These results may improve seasonal to decadal predictions of European climate.
Shipra Jain, Ruth M. Doherty, David Sexton, Steven Turnock, Chaofan Li, Zixuan Jia, Zongbo Shi, and Lin Pei
Atmos. Chem. Phys., 22, 7443–7460, https://doi.org/10.5194/acp-22-7443-2022, https://doi.org/10.5194/acp-22-7443-2022, 2022
Short summary
Short summary
We provide a range of future projections of winter haze and clear conditions over the North China Plain (NCP) using multiple simulations from a climate model for the high-emission scenario (RCP8.5). The frequency of haze conducive weather is likely to increase whereas the frequency of clear weather is likely to decrease in future. The total number of hazy days for a given winter can be as much as ˜3.5 times higher than the number of clear days over the NCP.
Antonio Capponi, Natalie J. Harvey, Helen F. Dacre, Keith Beven, Cameron Saint, Cathie Wells, and Mike R. James
Atmos. Chem. Phys., 22, 6115–6134, https://doi.org/10.5194/acp-22-6115-2022, https://doi.org/10.5194/acp-22-6115-2022, 2022
Short summary
Short summary
Forecasts of the dispersal of volcanic ash in the atmosphere are hampered by uncertainties in parameters describing the characteristics of volcanic plumes. Uncertainty quantification is vital for making robust flight-planning decisions. We present a method using satellite data to refine a series of volcanic ash dispersion forecasts and quantify these uncertainties. We show how we can improve forecast accuracy and potentially reduce the regions of high risk of volcanic ash relevant to aviation.
Piyush Srivastava, Ian M. Brooks, John Prytherch, Dominic J. Salisbury, Andrew D. Elvidge, Ian A. Renfrew, and Margaret J. Yelland
Atmos. Chem. Phys., 22, 4763–4778, https://doi.org/10.5194/acp-22-4763-2022, https://doi.org/10.5194/acp-22-4763-2022, 2022
Short summary
Short summary
The parameterization of surface turbulent fluxes over sea ice remains a weak point in weather forecast and climate models. Recent theoretical developments have introduced more extensive physics but these descriptions are poorly constrained due to a lack of observation data. Here we utilize a large dataset of measurements of turbulent fluxes over sea ice to tune the state-of-the-art parameterization of wind stress, and compare it with a previous scheme.
Yiqing Liu, Zhiwen Luo, and Sue Grimmond
Atmos. Chem. Phys., 22, 4721–4735, https://doi.org/10.5194/acp-22-4721-2022, https://doi.org/10.5194/acp-22-4721-2022, 2022
Short summary
Short summary
Anthropogenic heat emission from buildings is important for atmospheric modelling in cities. The current building anthropogenic heat flux is simplified by building energy consumption. Our research proposes a novel approach to determine ‘real’ building anthropogenic heat emission from the changes in energy balance fluxes between occupied and unoccupied buildings. We hope to provide new insights into future parameterisations of building anthropogenic heat flux in urban climate models.
Lars Hoffmann and Reinhold Spang
Atmos. Chem. Phys., 22, 4019–4046, https://doi.org/10.5194/acp-22-4019-2022, https://doi.org/10.5194/acp-22-4019-2022, 2022
Short summary
Short summary
We present an intercomparison of 2009–2018 lapse rate tropopause characteristics as derived from ECMWF's ERA5 and ERA-Interim reanalyses. Large-scale features are similar, but ERA5 shows notably larger variability, which we mainly attribute to UTLS temperature fluctuations due to gravity waves being better resolved by ECMWF's IFS forecast model. Following evaluation with radiosondes and GPS data, we conclude ERA5 will be a more suitable asset for tropopause-related studies in future work.
Linye Song, Shangfeng Chen, Wen Chen, Jianping Guo, Conglan Cheng, and Yong Wang
Atmos. Chem. Phys., 22, 1669–1688, https://doi.org/10.5194/acp-22-1669-2022, https://doi.org/10.5194/acp-22-1669-2022, 2022
Short summary
Short summary
This study shows that in most years when haze pollution (HP) over the North China Plain (NCP) is more (less) serious in winter, air conditions in the following spring are also worse (better) than normal. Conversely, there are some years when HP in the following spring is opposed to that in winter. It is found that North Atlantic sea surface temperature (SST) anomalies play important roles in HP evolution over the NCP. Thus North Atlantic SST is an important preceding signal for NCP HP evolution.
Anna A. Shestakova, Dmitry G. Chechin, Christof Lüpkes, Jörg Hartmann, and Marion Maturilli
Atmos. Chem. Phys., 22, 1529–1548, https://doi.org/10.5194/acp-22-1529-2022, https://doi.org/10.5194/acp-22-1529-2022, 2022
Short summary
Short summary
This article presents a comprehensive analysis of the easterly orographic wind episode which occurred over Svalbard on 30–31 May 2017. This wind caused a significant temperature rise on the lee side of the mountains and greatly intensified the snowmelt. This episode was investigated on the basis of measurements collected during the ACLOUD/PASCAL field campaigns with the help of numerical modeling.
Xiadong An, Lifang Sheng, Chun Li, Wen Chen, Yulian Tang, and Jingliang Huangfu
Atmos. Chem. Phys., 22, 725–738, https://doi.org/10.5194/acp-22-725-2022, https://doi.org/10.5194/acp-22-725-2022, 2022
Short summary
Short summary
The North China Plain (NCP) suffered many periods of haze in winter during 1985–2015, related to the rainfall-induced diabatic heating over southern China. The haze over the NCP is modulated by an anomalous anticyclone caused by the Rossby wave and a north–south circulation (NSC) induced mainly by diabatic heating. As a Rossby wave source, rainfall-induced diabatic heating supports waves and finally strengthens the anticyclone over the NCP. These changes favor haze over the NCP.
Cited articles
Adam, O., Schneider, T., and Harnik, N.: Role of Changes in Mean Temperatures versus Temperature Gradients in the Recent Widening of the Hadley Circulation, J. Climate, 27, 7450–7461, https://doi.org/10.1175/JCLI-D-14-00140.1, 2014.
Allen, R. J. and Sherwood, S. C.: The impact of natural versus anthropogenic aerosols on atmospheric circulation in the Community Atmosphere Model, Clim. Dynam., 36, 1959–1978, https://doi.org/10.1007/s00382-010-0898-8, 2011.
Allen, R. J., Sherwood, S. C., Norris, J. R., and Zender, C. S.: Recent Northern Hemisphere tropical expansion primarily driven by black carbon and tropospheric ozone, Nature, 485, 350–354, https://doi.org/10.1038/nature11097, 2012.
Allen, R. J., Norris, J. R., and Kovilakam, M.: Influence of anthropogenic aerosols and the Pacific Decadal Oscillation on tropical belt width, Nat. Geosci., 7, 270–274, https://doi.org/10.1038/ngeo2091, 2014.
Ao, C. O. and Hajj, A. J.: Monitoring the width of the tropical belt with GPS radio occultation measurements, Geophys. Res. Lett., 40, 6236–6241, https://doi.org/10.1002/2013GL058203, 2013.
Archer, C. L. and Caldeira, K.: Historical trends in the jet streams, Geophys. Res. Lett., L08803, https://doi.org/10.1029/2008GL033614, 2008.
Barnes, E. A. and Polvani, L.: Response of the Midlatitude Jets, and of Their Variability, to Increased Greenhouse Gases in the CMIP5 Models, J. Climate, 26, 7117–7135, https://doi.org/10.1175/JCLI-D-12-00536.1, 2013.
Bengtsson, L., Hodges, K. I., and Hagemann, S.: Sensitivity of the ERA40 reanalysis to the observing system: determination of the global atmospheric circulation from reduced observations, Tellus A, 56, 456–471, https://doi.org/10.1111/j.1600-0870.2004.00079.x, 2004.
Birner, T.: Recent widening of the tropical belt from global tropopause statistics: Sensitivities, J. Geophys. Res., 115, D23109, https://doi.org/10.1029/2010JD014664, 2010.
Birner, T., Davis, S. M., and Seidel, D. J.: The changing width of Earth's tropical belt, Phys. Today, 67, 38–44, https://doi.org/10.1063/PT.3.2620, 2014.
Bretherton, C. S., Widmann, M., Dymnikov, V. P., Wallace, J. M., and Blade, I.: The Effective Number of Spatial Degrees of Freedom of a Time-Varying Field, J. Climate, 12, 1990–2009, https://doi.org/10.1175/1520-0442(1999)012<1990:TENOSD>2.0.CO;2, 1999.
Burt, M. A., Randall, D. A., and Branson, M. D.: Dark Warming, J. Climate, 29, 705–718, https://doi.org/10.1175/JCLI-D-15-0147.1, 2015.
Butler, A. H., Thompson, D. W. J., and Heikes, R.: The Steady-State Atmospheric Circulation Response to Climate Change-like Thermal Forcings in a Simple General Circulation Model, J. Climate, 23, 3474–3496, https://doi.org/10.1175/2010JCLI3228.1, 2010.
Ceppi, P. and Hartmann, D. L.: On the Speed of the Eddy-Driven Jet and the Width of the Hadley Cell in the Southern Hemisphere, J. Climate, 26, 3450–3465, https://doi.org/10.1175/JCLI-D-12-00414.1, 2013.
Ceppi, P., Hwang, Y.-T., Frierson, D. M. W., and Hartmann, D. L.: Southern Hemisphere jet latitude biases in CMIP5 models linked to shortwave cloud forcing, Geophys. Res. Lett., 39, L19708, https://doi.org/10.1029/2012GL053115, 2012.
Ceppi, P., Zelinka, M. D., and Hartmann, D. L.: The response of the Southern Hemispheric eddy-driven jet to future changes in shortwave radiation in CMIP5, Geophys. Res. Lett., 41, 3244–3250, https://doi.org/10.1002/2014GL060043, 2014.
Chen, G. and Held, I. M.: Phase speed spectra and the recent poleward shift of Southern Hemisphere surface westerlies, Geophys. Res. Lett., 34, L21805, https://doi.org/10.1029/2007GL031200, 2007.
Chen, S., Wei, K., Chen, W., and Song, L.: Regional changes in the annual mean Hadley circulation in recent decades, J. Geophys. Res., 119, 7815–7832, https://doi.org/10.1002/2014JD021540, 2014.
Choi, J., Son, S.-W., Lu, J., and Min, S.-K.: Further observational evidence of Hadley cell widening in the Southern Hemisphere, J. Climate, 27, 5538–5559, https://doi.org/10.1002/2014GL059426, 2014.
Davis, N. A. and Birner, T.: Seasonal to multi-decadal variability of the width of the tropical belt, J. Geophys. Res., 118, 7773–7787, https://doi.org/10.1002/jgrd.50610, 2013.
Davis, N. A. and Birner, T.: Climate model biases in the width of the tropical belt, J. Climate, 29, 1935–1954, https://doi.org/10.1175/JCLI-D-15-0336.1, 2016.
Davis, S. M. and Rosenlof, K. H.: A Multidiagnostic Intercomparison of Tropical-Width Time Series Using Reanalyses and Satellite Observations, J. Climate, 25, 1061–1078, https://doi.org/10.1175/JCLI-D-11-00127.1, 2012.
Dorigo, W., de Jeu, R., Chung, D., Parinussa, R., Liu, Y., Wagner, W., and Fernàndez-Prieto, D.: Evaluating global trends (1988–2010) in harmonized multi-satellite surface soil moisture, Geophys. Res. Lett., 39, L18405, https://doi.org/10.1029/2012GL052988, 2012.
Feldl, N. and Bordoni, S.: Characterizing the Hadley Circulation Response through Regional Climate Feedbacks, J. Climate, 29, 613–622, https://doi.org/10.1175/JCLI-D-15-0424.1, 2016.
Feng, S. and Fu, Q.: Expansion of global drylands under a warming climate, Atmos. Chem. Phys., 13, 10081–10094, https://doi.org/10.5194/acp-13-10081-2013, 2013.
Frierson, D. M. W.: The Dynamics of Idealized Convection Schemes and Their Effect on the Zonally Averaged Tropical Circulation, J. Atmos. Sci., 64, 1959–1976, https://doi.org/10.1175/JAS3935.1, 2007.
Frierson, D. M. W., Lu, J., and Chen, G.: Width of the Hadley cell in simple and comprehensive general circulation models, Geophys. Res. Lett., 34, L18804, https://doi.org/10.1029/2007GL031115, 2007.
Fu, Q. and Lin, P.: Poleward Shift of Subtropical Jets Inferred from Satellite-Observed Lower Stratospheric Temperatures, J. Climate, 24, 5597–5603, https://doi.org/10.1175/JCLI-D-11-00027.1, 2011.
Garfinkel, C. I., Waugh, D. W., and Polvani, L. M.: Recent Hadley cell expansion: The role of internal atmospheric variability in reconciling modeled and observed trends, Geophys. Res. Lett., 42, 10824–10831, https://doi.org/10.1002/2015GL066942, 2015.
Gastineau, G., Treut, H. L., and Li, L.: Hadley circulation changes under global warming conditions indicated by coupled climate models, Tellus, 60A, 863–884, https://doi.org/10.1111/j.1600-0870.2008.00344.x, 2008.
Grassi, B., Redaelli, G., Canziani, P. O., and Visconti, G.: Effect of the PDO Phase on the Tropical Belt Width, J. Climate, 25, 3282–3290, https://doi.org/10.1175/JCLI-D-11-00244.1, 2012.
Grise, K. M. and Polvani, L. M.: Is climate sensitivity related to dynamical sensitivity? A Southern Hemisphere perspective, Geophys. Res. Lett., 41, 534–540, https://doi.org/10.1002/2013GL058466, 2014.
Grise, K. M. and Polvani, L. M.: Is climate sensitivity related to dynamical sensitivity?, J. Geophys. Res., 121, 5159–5176, https://doi.org/10.1002/2015JD024687, 2016.
Hawkins, E. and Sutton, R.: The potential to Narrow Uncertainty in Regional Climate Predictions, B. Am. Meteorol. Soc., 90, 1095–1107, https://doi.org/10.1175/2009BAMS2607.1, 2009.
Held, I. M.: The general circulation of the atmosphere, in: 2000 Program in Geophysical Fluid Dynamics, Woods Hole Oceanographic Institude, Woods Hole, Mass., 30–36, 2000.
Held, I. M. and Soden, B. J.: Robust Responses of the Hydrological Cycle to Global Warming, J. Climate, 19, 5685–5699, https://doi.org/10.1175/JCLI3990.1, 2006.
Held, I. M., Hemler, R. S., and Ramaswamy, V.: Radiative-Convective Equilibrium with Explicit Two-Dimensional Moist Convection, J. Atmos. Sci., 50, 3909–3927, https://doi.org/10.1175/1520-0469(1993)050<3909:RCEWET>2.0.CO;2, 1993.
Helm, K. P., Bindoff, N. L., and Church, J. A.: Changes in the global hydrological-cycle inferred from ocean salinity, Geophys. Res. Lett., 37, L18701, https://doi.org/10.1029/2010GL044222, 2010.
Hu, Y. and Fu, Q.: Observed poleward expansion of the Hadley circulation since 1979, Atmos. Chem. Phys., 7, 5229–5236, https://doi.org/10.5194/acp-7-5229-2007, 2007.
Hu, Y., Zhou, C., and Liu, J.: Observational evidence for the poleward expansion of the Hadley circulation, Adv. Atmos. Sci., 28, 33–44, https://doi.org/10.1007/s00376-010-0032-1, 2011.
Hu, Y., Tao, L., and Liu, J.: Poleward Expansion of the Hadley Circulation in CMIP5 Simulations, Adv. Atmos. Sci., 30, 790–795, https://doi.org/10.1007/s00376-012-2187-4, 2013.
Hudson, R. D.: Measurements of the movement of the jet streams at mid-latitudes, in the Northern and Southern Hemispheres, 1979 to 2010, Atmos. Chem. Phys., 12, 7797–7808, https://doi.org/10.5194/acp-12-7797-2012, 2012.
Hudson, R. D., Frolov, A. D., Andrade, M. F., and Follette, M. B.: The total ozone field separated into meteorological regimes, J. Atmos. Sci., 60, 1669–1677, https://doi.org/10.1175/1520-0469(2003)060<1669:TTOFSI>2.0.CO;2, 2003.
Huneeus, N., Boucher, O., Alterskjær, K., Cole, J. N. S., Curry, C. L., Ji, D., Jones, A., Kravitz, B., Kristjánsson, J. E., Moore, J. C., Muri, H., Niemeier, U., Rasch, P., Robock, A., Singh, B., Schmidt, H., Schulz, M., Tilmes, S., Watanabe, S., and Yoon, J.-H.: Forcings and feedbacks in the GeoMIP ensemble for a reduction in solar irradiance and increase in CO2, J. Geophys. Res., 119, 5226–5239, https://doi.org/10.1002/2013JD021110, 2014.
Johanson, C. M. and Fu, Q.: Hadley Cell Widening: Model Simulations versus Observations, J. Climate, 22, 2713–2725, https://doi.org/10.1175/2008JCLI2620.1, 2009.
Kang, S. M. and Lu, J.: Expansion of the Hadley Cell under Global Warming: Winter versus Summer, J. Climate, 25, 8387–8393, https://doi.org/10.1175/JCLI-D-12-00323.1, 2012.
Kang, S. M. and Polvani, L. M.: The interannual relationship between the eddy-driven jet and the edge of the Hadley cell, J. Climate, 24, 563–568, https://doi.org/10.1175/2010JCLI4077.1, 2011.
Karnauskas, K. B. and Ummenhofer, C. C.: On the dynamics of the Hadley circulation and subtropical drying, Clim. Dynam., 42, 2259–2269, https://doi.org/10.1007/s00382-014-2129-1, 2014.
Kidston, J. and Gerber, E. P.: Intermodel variability of the poleward shift of the austral jet stream in the CMIP3 integrations linked to biases in 20th century climatology, Geophys. Res. Lett., 37, L09708, https://doi.org/10.1029/2010GL042873, 2010.
Korty, R. L. and Schneider, T.: Extent of Hadley circulations in dry atmospheres, Geophys. Res. Lett., 35, L23803, https://doi.org/10.1029/2008GL035847, 2008.
Kravitz, B., Robock, A., Boucher, O., Schmidt, H., Taylor, K. E., Stenchikov, G., and Schulz, M.: The Geoengineering Model Intercomparison Project (GeoMIP), Atmos. Sci. Lett., 12, 162–167, https://doi.org/10.1002/asl.316, 2011.
Kushner, P. J. and Polvani, L. M.: Stratosphere-troposphere coupling in a relatively simple AGCM: The role of eddies, J. Climate, 17, 629–639, https://doi.org/10.1175/JCLI4007.1, 2004.
Landu, K., Leung, L. R., Hagos, S., Vinoj, V., Rauscher, S. A., Ringler, T., and Taylor, M.: The Dependence of ITCZ Structure on Model Resolution and Dynamical Core in Aquaplanet Simulations, J. Climate, 27, 2375–2385, https://doi.org/10.1175/JCLI-D-13-00269.1, 2014.
Levine, X. J. and Schneider, T.: Baroclinic Eddies and the Extent of the Hadley Circulation: An Idealized GCM Study, J. Atmos. Sci., 72, 2744–2761, https://doi.org/10.1175/JAS-D-14-0152.1, 2015.
Lorant, V. and Royer, J.-F.: Sensitivity of Equatorial Convection to Horizontal Resolution in Aquaplanet Simulations with a Variable-Resolution GCM, Mon. Weather Rev., 129, 2730–2745, https://doi.org/10.1175/1520-0493(2001)129<2730:SOECTH>2.0.CO;2, 2001.
Lorenz, D. J. and DeWeaver, E. T.: Tropopause height and zonal wind response to global warming in the IPCC scenario intergrations, J. Geophys. Res., 112, D10119, https://doi.org/10.1029/2006JD008087, 2007.
Lu, J., Vecchi, G. A., and Reichler, T.: Expansion of the Hadley cell under global warming, Geophys. Res. Lett., 118, L06805, https://doi.org/10.1029/2006GL028443, 2007.
Lu, J., Chen, G., and Frierson, D. M. W.: Response of the Zonal Mean Atmospheric Circulation to El Niño versus Global Warming, J. Climate, 21, 5835–5851, https://doi.org/10.1175/2008JCLI2200.1, 2008.
Lu, J., Deser, C., and Reichler, T.: Cause of the widening of the tropical belt since 1958, Geophys. Res. Lett., L03802, https://doi.org/10.1029/2008GL036076, 2009.
Lucas, C. and Nguyen, H.: Regional characteristics of tropical expansion and the role of climate variability, J. Geophys. Res., 120, 6809–6824, https://doi.org/10.1002/2015JD023130, 2015.
Lucas, C., Nguyen, H., and Timbal, B.: An observational analysis of Southern Hemisphere tropical expansion, J. Geophys. Res., 117, D17112, https://doi.org/10.1029/2011JD017033, 2012.
Lucas, C., Timbal, B., and Nguyen, H.: The expanding tropics: a critical assessment of the observational and modeling studies, WIREs Clim. Change, 5, 89–112, https://doi.org/10.1002/wcc.251, 2014.
Manabe, S. and Wetherald, R. T.: Thermal Equilibrium of the Atmosphere with a Given Distribution of Relative Humidity, J. Atmos. Sci., 24, 241–259, https://doi.org/10.1175/1520-0469(1967)024<0241:TEOTAW>2.0.CO;2, 1967.
Maycock, A. C., Joshi, M. M., Shine, K. P., and Scaife, A. A.: The Circulation Response to Idealized Changes in Stratospheric Water Vapor, J. Climate, 26, 545–561, https://doi.org/10.1175/JCLI-D-12-00155.1, 2013.
McLandress, C., Shepherd, T. G., Scinocca, J. F., Plummer, D. A., Sigmond, M., Jonsson, A. I., and Reader, M. C.: Separating the Dynamical Effects of Climate Change and Ozone Depletion. Part II: Southern Hemisphere Troposphere, J. Climate, 24, 1850–1868, https://doi.org/10.1175/2010JCLI3586.1, 2011.
Min, S.-K. and Son, S.-W.: Multimodel attribution of the Southern Hemisphere Hadley cell widening: Major role of ozone depletion, J. Geophys. Res., 118, 3007–3015, https://doi.org/10.1002/jgrd.50232, 2013.
Mitas, C. M. and Clement, A.: Recent behavior of the Hadley cell and tropical thermodynamics in climate models and reanalyses, Geophys. Res. Lett., 33, L01810, https://doi.org/10.1029/2005GL024406, 2006.
National Research Council: Climate Intervention: Reflecting Sunlight to Cool Earth, Washington, D. C., https://doi.org/10.17226/18988, 2015.
New, M., Todd, M., Hulme, M., and Jones, P.: Precipitation measurements and trends in the twentieth century, Int. J. Climatol., 21, 1899–1922, https://doi.org/10.1002/joc.680, 2001.
Nguyen, H., Evans, A., Lucas, C., Smith, I., and Timbal, B.: The Hadley circulation in reanalyses: climatology, variability and expansion, J. Climate, 26, 3357–3376, https://doi.org/10.1175/JCLI-D-12-00224.1, 2013.
Phillips, N. A.: A simple three-dimensional model for the study of larger-scale extratropical flow patterns, J. Meteorol., 8, 381–394, https://doi.org/10.1175/1520-0469(1951)008<0381:ASTDMF>2.0.CO;2, 1951.
Pithan, F. and Mauritsen, T.: Arctic amplification dominated by temperature feedbacks in contemporary climate models, Nat. Geosci., 7, 181–184, https://doi.org/10.1038/ngeo2071, 2014.
Polvani, L. M. and Kushner, P. J.: Tropospheric response to stratospheric perturbations in a relatively simple general circulation model, Geophys. Res. Lett., 29, L014284, https://doi.org/10.1029/2001GL014284, 2002.
Polvani, L. M., Previdi, M., and Deser, C.: Large cancellation, due to ozone recory, of future Southern Hemisphere atmospheric circulations trends, Geophys. Res. Lett., 38, L04707, https://doi.org/10.1029/2011GL046712, 2011a.
Polvani, L. M., Waugh, D. W., Correa, G. J. P., and Son, S.-W.: Stratospheric ozone depletion: the main driver of 20th Century atmospheric circulation changes in the Southern Hemisphere, J. Climate, 24, 795–812, https://doi.org/10.1175/2010JCLI3772.1, 2011b.
Romps, D. M.: Response of Tropical Precipitation to Global Warming, J. Atmos. Sci., 68, 123–138, https://doi.org/10.1175/2010JAS3542.1, 2011.
Scheff, J. and Frierson, D. M. W.: Robust future precipitation declines in CMIP5 largely reflect the poleward expansion of model subtropical dry zones, Geophys. Res. Lett., 39, L18704, https://doi.org/10.1029/2012GL052910, 2012.
Schneider, T.: The general circulation of the atmosphere, Annu. Rev. Earth Pl. Sc., 34, 655–688, https://doi.org/10.1146/annurev.earth.34.031405.125144, 2006.
Schneider, T. and Bordoni, S.: Eddy-Mediated Regime Transitions in the Seasonal Cycle of a Hadley Circulation and Implications for Monsoon Dynamics, J. Atmos. Sci., 65, 915–933, https://doi.org/10.1175/2007JAS2415.1, 2008.
Seidel, D. J. and Randel, W. J.: Recent widening of the tropical belt: Evidence from tropopause observations, J. Geophys. Res., 112, D20113, https://doi.org/10.1029/2007JD008861, 2007.
Shaw, T. A. and Voigt, A.: Tug of war on summertime circulation between radiative forcing and sea surface warming, Nat. Geosci., 8, 560–566, https://doi.org/10.1038/ngeo2449, 2015.
Son, S.-W., Tandon, N. F., Polvani, L. M., and Waugh, D. W.: Ozone hole and Southern Hemisphere climate change, Geophys. Res. Lett., 36, L15605, https://doi.org/10.1029/2009GL038671, 2009.
Stachnik, J. P. and Schumacher, C.: A comparison of the Hadley circulation in modern reanalyses, J. Geophys. Res., 116, D22102, https://doi.org/10.1029/2011JD016677, 2011.
Staten, P. W. and Reichler, T.: On the ratio between shifts in the eddy-driven jet and the Hadley cell edge, Clim. Dynam., 42, 1229–1242, https://doi.org/10.1007/s00382-013-1905-7, 2014.
Tandon, N. F., Polvani, L. M., and Davis, S. M.: The response of the tropospheric circulation to water vapor-like forcings in the stratosphere, J. Climate, 24, 5713–5720, https://doi.org/10.1175/JCLI-D-11-00069.1, 2011.
Tandon, N. F., Gerber, E. P., Sobel, A. H., and Polvani, L. M.: Understanding Hadley Cell expansion versus contraction: insights from simplified models and implications for recent observations, J. Climate, 26, 4304–4321, https://doi.org/10.1175/JCLI-D-12-00598.1, 2013.
Tao, L., Hu, Y., and Liu, J.: Anthropogenic forcing on the Hadley circulation in CMIP5 simulations, Clim. Dynam., 46, 3337–3350, https://doi.org/10.1007/s00382-015-2772-1, 2015.
Taylor, K. E., Stouffer, R. J., and Meehl, G. A.: An overview of CMIP5 and the experiment design, B. Am. Meteorol. Soc., 93, 485–498, https://doi.org/10.1175/BAMS-D-11-00094.1, 2012.
Trenberth, K. E., Stepaniak, D. P., Hurrell, J. W., and Fiorino, M.: Quality of Reanalyses in the Tropics, J. Climate, 14, 1499–1510, https://doi.org/10.1175/1520-0442(2001)014<1499:QORITT>2.0.CO;2, 2001.
Vallis, G. K., Zurita-Gotor, P., Cairns, C., and Kidston, J.: Response of the large-scale structure of the atmosphere to global warming, Q. J. Roy. Meteor. Soc., 141, 1479–1501, https://doi.org/10.1002/qj.2456, 2015.
Vecchi, G. A. and Soden, B. J.: Global warmng and the weakening of the tropical circulation, J. Climate, 20, 4316–4340, https://doi.org/10.1175/JCLI4258.1, 2007.
Voigt, A. and Shaw, T. A.: Circulation response to warming shaped by radiative changes of clouds and water vapour, Nat. Geosci., 8, 102–106, https://doi.org/10.1038/ngeo2345, 2015.
Waugh, D. W., Garfinkel, C. I., and Polvani, L. M.: Drivers of the Recent Tropical Expansion in the Southern Hemisphere: Changing SSTs or Ozone Depletion?, J. Climate, 28, 6581–6586, https://doi.org/10.1175/JCLI-D-15-0138.1, 2015.
Zhang, X., Zwiers, F. W., Hegerl, G. C., Lambert, F. H., Gillett, N. P., Solomon, S., Stott, P. A., and Nozawa, T.: Detection of human influence on twentieth-century precipitation trends, Nature, 448, 461–465, https://doi.org/10.1038/nature06025, 2007.
Short summary
In the Hadley cells, air rises at the Equator and sinks over the subtropics, drying the air and creating deserts on land. We investigated simple climate model experiments and found that the Hadley cells expand in response to increasing carbon dioxide. The climate of some models warms more than others, and these models also have greater Hadley cell expansion. This expansion could shift deserts toward more populated areas, with potentially major impacts on water resources and surface climate.
In the Hadley cells, air rises at the Equator and sinks over the subtropics, drying the air and...
Altmetrics
Final-revised paper
Preprint