Articles | Volume 21, issue 8
https://doi.org/10.5194/acp-21-5821-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-21-5821-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
19 Apr 2021
Research article |
| 19 Apr 2021
| 19 Apr 2021
Anthropogenic aerosol forcing of the Atlantic meridional overturning circulation and the associated mechanisms in CMIP6 models
Department of Earth and Planetary Sciences, University of California Riverside, Riverside, CA 92521, USA
Department of Earth and Planetary Sciences, University of California Riverside, Riverside, CA 92521, USA
Wei Liu
Department of Earth and Planetary Sciences, University of California Riverside, Riverside, CA 92521, USA
Cynthia A. Randles
ExxonMobil Research and Engineering Company, Annandale, NJ 08801, USA
Related authors
Jianfeng Li, Kai Zhang, Taufiq Hassan, Shixuan Zhang, Po-Lun Ma, Balwinder Singh, Qiyang Yan, and Huilin Huang
Geosci. Model Dev., 17, 1327–1347, https://doi.org/10.5194/gmd-17-1327-2024, https://doi.org/10.5194/gmd-17-1327-2024, 2024
Short summary
Short summary
By comparing E3SM simulations with and without regional refinement, we find that model horizontal grid spacing considerably affects the simulated aerosol mass budget, aerosol–cloud interactions, and the effective radiative forcing of anthropogenic aerosols. The study identifies the critical physical processes strongly influenced by model resolution. It also highlights the benefit of applying regional refinement in future modeling studies at higher or even convection-permitting resolutions.
Taufiq Hassan, Kai Zhang, Jianfeng Li, Balwinder Singh, Shixuan Zhang, Hailong Wang, and Po-Lun Ma
EGUsphere, https://doi.org/10.5194/egusphere-2023-1055, https://doi.org/10.5194/egusphere-2023-1055, 2023
Short summary
Short summary
Anthropogenic aerosol emissions are essential part of the global aerosol models. Significant errors can exist from the loss of emission heterogeneity. We introduced an emission treatment that significantly improved aerosol emission heterogeneity in high-resolution model simulations, with improvements in simulated aerosol surface concentrations. The emission treatment will provide a more accurate representation of aerosol emissions and their effects on climate.
Robert J. Allen, Xueying Zhao, Cynthia A. Randles, Ryan J. Kramer, Bjorn H. Samset, and Christopher J. Smith
EGUsphere, https://doi.org/10.5194/egusphere-2024-872, https://doi.org/10.5194/egusphere-2024-872, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Present-day methane shortwave absorption mutes 29 % of the surface warming and 66 % of the precipitation increase associated with its longwave absorption. The muting effect of present-day methane shortwave absorption is about five times larger as compared to that under idealized carbon dioxide perturbations.
Stephanie Fiedler, Vaishali Naik, Fiona M. O'Connor, Christopher J. Smith, Paul Griffiths, Ryan J. Kramer, Toshihiko Takemura, Robert J. Allen, Ulas Im, Matthew Kasoar, Angshuman Modak, Steven Turnock, Apostolos Voulgarakis, Duncan Watson-Parris, Daniel M. Westervelt, Laura J. Wilcox, Alcide Zhao, William J. Collins, Michael Schulz, Gunnar Myhre, and Piers M. Forster
Geosci. Model Dev., 17, 2387–2417, https://doi.org/10.5194/gmd-17-2387-2024, https://doi.org/10.5194/gmd-17-2387-2024, 2024
Short summary
Short summary
Climate scientists want to better understand modern climate change. Thus, climate model experiments are performed and compared. The results of climate model experiments differ, as assessed in the latest Intergovernmental Panel on Climate Change (IPCC) assessment report. This article gives insights into the challenges and outlines opportunities for further improving the understanding of climate change. It is based on views of a group of experts in atmospheric composition–climate interactions.
Jianfeng Li, Kai Zhang, Taufiq Hassan, Shixuan Zhang, Po-Lun Ma, Balwinder Singh, Qiyang Yan, and Huilin Huang
Geosci. Model Dev., 17, 1327–1347, https://doi.org/10.5194/gmd-17-1327-2024, https://doi.org/10.5194/gmd-17-1327-2024, 2024
Short summary
Short summary
By comparing E3SM simulations with and without regional refinement, we find that model horizontal grid spacing considerably affects the simulated aerosol mass budget, aerosol–cloud interactions, and the effective radiative forcing of anthropogenic aerosols. The study identifies the critical physical processes strongly influenced by model resolution. It also highlights the benefit of applying regional refinement in future modeling studies at higher or even convection-permitting resolutions.
James L. Gomez, Robert J. Allen, and King-Fai Li
EGUsphere, https://doi.org/10.5194/egusphere-2023-2827, https://doi.org/10.5194/egusphere-2023-2827, 2024
Short summary
Short summary
Wildfires in the southwestern United States have grown very large throughout the last 20 years. These fires emit sunlight absorbing aerosols. Our study finds that aerosols emitted from fires in northern California spread throughout California and Nevada, warming the atmosphere. The warmer temperatures remove clouds from the atmosphere. This may lead to surface warming, as well as decreases in rain in the region affected. This could create conditions that prolong the fires and their consequences.
Alkiviadis Kalisoras, Aristeidis K. Georgoulias, Dimitris Akritidis, Robert J. Allen, Vaishali Naik, Chaincy Kuo, Sophie Szopa, Pierre Nabat, Dirk Olivié, Twan van Noije, Philippe Le Sager, David Neubauer, Naga Oshima, Jane Mulcahy, Larry W. Horowitz, and Prodromos Zanis
EGUsphere, https://doi.org/10.5194/egusphere-2023-2571, https://doi.org/10.5194/egusphere-2023-2571, 2023
Short summary
Short summary
Effective Radiative Forcing (ERF) is a metric for estimating how human activities and natural agents change the energy flow into and out of the Earth’s climate system. We investigate the anthropogenic aerosol ERF and we estimate the contribution of individual processes to the total ERF using simulations from Earth System Models within the Coupled Model Intercomparison Project Phase 6 (CMIP6). Our findings highlight that aerosol-cloud interactions drive ERF variability during the last 150 years.
Laura J. Wilcox, Robert J. Allen, Bjørn H. Samset, Massimo A. Bollasina, Paul T. Griffiths, James Keeble, Marianne T. Lund, Risto Makkonen, Joonas Merikanto, Declan O'Donnell, David J. Paynter, Geeta G. Persad, Steven T. Rumbold, Toshihiko Takemura, Kostas Tsigaridis, Sabine Undorf, and Daniel M. Westervelt
Geosci. Model Dev., 16, 4451–4479, https://doi.org/10.5194/gmd-16-4451-2023, https://doi.org/10.5194/gmd-16-4451-2023, 2023
Short summary
Short summary
Changes in anthropogenic aerosol emissions have strongly contributed to global and regional climate change. However, the size of these regional impacts and the way they arise are still uncertain. With large changes in aerosol emissions a possibility over the next few decades, it is important to better quantify the potential role of aerosol in future regional climate change. The Regional Aerosol Model Intercomparison Project will deliver experiments designed to facilitate this.
Taufiq Hassan, Kai Zhang, Jianfeng Li, Balwinder Singh, Shixuan Zhang, Hailong Wang, and Po-Lun Ma
EGUsphere, https://doi.org/10.5194/egusphere-2023-1055, https://doi.org/10.5194/egusphere-2023-1055, 2023
Short summary
Short summary
Anthropogenic aerosol emissions are essential part of the global aerosol models. Significant errors can exist from the loss of emission heterogeneity. We introduced an emission treatment that significantly improved aerosol emission heterogeneity in high-resolution model simulations, with improvements in simulated aerosol surface concentrations. The emission treatment will provide a more accurate representation of aerosol emissions and their effects on climate.
Daniel J. Varon, Daniel J. Jacob, Melissa Sulprizio, Lucas A. Estrada, William B. Downs, Lu Shen, Sarah E. Hancock, Hannah Nesser, Zhen Qu, Elise Penn, Zichong Chen, Xiao Lu, Alba Lorente, Ashutosh Tewari, and Cynthia A. Randles
Geosci. Model Dev., 15, 5787–5805, https://doi.org/10.5194/gmd-15-5787-2022, https://doi.org/10.5194/gmd-15-5787-2022, 2022
Short summary
Short summary
Reducing atmospheric methane emissions is critical to slow near-term climate change. Globally surveying satellite instruments like the TROPOspheric Monitoring Instrument (TROPOMI) have unique capabilities for monitoring atmospheric methane around the world. Here we present a user-friendly cloud-computing tool that enables researchers and stakeholders to quantify methane emissions across user-selected regions of interest using TROPOMI satellite observations.
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.
María A. Burgos, Elisabeth Andrews, Gloria Titos, Angela Benedetti, Huisheng Bian, Virginie Buchard, Gabriele Curci, Zak Kipling, Alf Kirkevåg, Harri Kokkola, Anton Laakso, Julie Letertre-Danczak, Marianne T. Lund, Hitoshi Matsui, Gunnar Myhre, Cynthia Randles, Michael Schulz, Twan van Noije, Kai Zhang, Lucas Alados-Arboledas, Urs Baltensperger, Anne Jefferson, James Sherman, Junying Sun, Ernest Weingartner, and Paul Zieger
Atmos. Chem. Phys., 20, 10231–10258, https://doi.org/10.5194/acp-20-10231-2020, https://doi.org/10.5194/acp-20-10231-2020, 2020
Short summary
Short summary
We investigate how well models represent the enhancement in scattering coefficients due to particle water uptake, and perform an evaluation of several implementation schemes used in ten Earth system models. Our results show the importance of the parameterization of hygroscopicity and model chemistry as drivers of some of the observed diversity amongst model estimates. The definition of dry conditions and the phenomena taking place in this relative humidity range also impact the model evaluation.
Robert J. Allen, Steven Turnock, Pierre Nabat, David Neubauer, Ulrike Lohmann, Dirk Olivié, Naga Oshima, Martine Michou, Tongwen Wu, Jie Zhang, Toshihiko Takemura, Michael Schulz, Kostas Tsigaridis, Susanne E. Bauer, Louisa Emmons, Larry Horowitz, Vaishali Naik, Twan van Noije, Tommi Bergman, Jean-Francois Lamarque, Prodromos Zanis, Ina Tegen, Daniel M. Westervelt, Philippe Le Sager, Peter Good, Sungbo Shim, Fiona O'Connor, Dimitris Akritidis, Aristeidis K. Georgoulias, Makoto Deushi, Lori T. Sentman, Jasmin G. John, Shinichiro Fujimori, and William J. Collins
Atmos. Chem. Phys., 20, 9641–9663, https://doi.org/10.5194/acp-20-9641-2020, https://doi.org/10.5194/acp-20-9641-2020, 2020
Prodromos Zanis, Dimitris Akritidis, Aristeidis K. Georgoulias, Robert J. Allen, Susanne E. Bauer, Olivier Boucher, Jason Cole, Ben Johnson, Makoto Deushi, Martine Michou, Jane Mulcahy, Pierre Nabat, Dirk Olivié, Naga Oshima, Adriana Sima, Michael Schulz, Toshihiko Takemura, and Konstantinos Tsigaridis
Atmos. Chem. Phys., 20, 8381–8404, https://doi.org/10.5194/acp-20-8381-2020, https://doi.org/10.5194/acp-20-8381-2020, 2020
Short summary
Short summary
In this work, we use Coupled Model Intercomparison Project Phase 6 (CMIP6) simulations from 10 Earth system models (ESMs) and general circulation models (GCMs) to study the fast climate responses on pre-industrial climate, due to present-day aerosols. All models carried out two sets of simulations: a control experiment with all forcings set to the year 1850 and a perturbation experiment with all forcings identical to the control, except for aerosols with precursor emissions set to the year 2014.
Daniel H. Cusworth, Daniel J. Jacob, Daniel J. Varon, Christopher Chan Miller, Xiong Liu, Kelly Chance, Andrew K. Thorpe, Riley M. Duren, Charles E. Miller, David R. Thompson, Christian Frankenberg, Luis Guanter, and Cynthia A. Randles
Atmos. Meas. Tech., 12, 5655–5668, https://doi.org/10.5194/amt-12-5655-2019, https://doi.org/10.5194/amt-12-5655-2019, 2019
Short summary
Short summary
We examine the potential for global detection of methane plumes from individual point sources with the new generation of spaceborne imaging spectrometers scheduled for launch in 2019–2025. We perform methane retrievals on simulated scenes with varying surfaces and atmospheric methane concentrations. Our results suggest that imaging spectrometers in space could play a transformative role in the future for quantifying methane emissions from point sources on a global scale.
Daniel H. Cusworth, Daniel J. Jacob, Jian-Xiong Sheng, Joshua Benmergui, Alexander J. Turner, Jeremy Brandman, Laurent White, and Cynthia A. Randles
Atmos. Chem. Phys., 18, 16885–16896, https://doi.org/10.5194/acp-18-16885-2018, https://doi.org/10.5194/acp-18-16885-2018, 2018
Short summary
Short summary
Methane emissions from oil/gas fields originate from a large number of small and densely clustered point sources. We examine the potential of recently launched or planned satellites to locate these high-mode emitters through measurements of atmospheric methane. We find that the recently launched TROPOMI and the planned GeoCARB instruments are successful at locating high-emitting sources for fields of 20-50 emitters within the 50 × 50 km2 geographic domain but are unsuccessful for denser fields.
Alexander J. Turner, Daniel J. Jacob, Joshua Benmergui, Jeremy Brandman, Laurent White, and Cynthia A. Randles
Atmos. Chem. Phys., 18, 8265–8278, https://doi.org/10.5194/acp-18-8265-2018, https://doi.org/10.5194/acp-18-8265-2018, 2018
Short summary
Short summary
We conduct a 1-week WRF-STILT simulation to generate methane column footprints at 1.3 km spatial resolution and hourly temporal resolution over the Barnett Shale. We find that a week of TROPOMI observations should provide regional (~30 km) information on temporally invariant sources and GeoCARB should provide information on temporally invariant sources at 2–7 km spatial resolution. An instrument precision better than 6 ppb is an important threshold for achieving fine resolution of emissions.
Anahita Amiri-Farahani, Robert J. Allen, David Neubauer, and Ulrike Lohmann
Atmos. Chem. Phys., 17, 6305–6322, https://doi.org/10.5194/acp-17-6305-2017, https://doi.org/10.5194/acp-17-6305-2017, 2017
Short summary
Short summary
We use observations from 2004 to 2012 to obtain estimates of the aerosol–cloud radiative effect, including its uncertainty, for dust aerosol influencing Atlantic marine stratocumulus clouds (MSc) off the coast of north Africa. Saharan dust modifies MSc in a way that acts to cool the planet. There is a strong seasonal variation, with the aerosol–cloud radiative effect switching from significantly negative during the boreal summer to weakly positive during boreal winter.
V. Buchard, A. M. da Silva, P. R. Colarco, A. Darmenov, C. A. Randles, R. Govindaraju, O. Torres, J. Campbell, and R. Spurr
Atmos. Chem. Phys., 15, 5743–5760, https://doi.org/10.5194/acp-15-5743-2015, https://doi.org/10.5194/acp-15-5743-2015, 2015
Short summary
Short summary
MERRAero is an aerosol reanalysis based on the GEOS-5 earth system model that incorporates an online aerosol module and assimilation of AOD from MODIS sensors. This study assesses the quality of MERRAero absorption using independent OMI observations. In addition to comparisons to OMI absorption AOD, we have developed a radiative transfer interface to simulate the UV aerosol index from assimilated aerosol fields at OMI footprint. Also, we fully diagnose the model using MISR, AERONET and CALIPSO.
C. A. Randles, S. Kinne, G. Myhre, M. Schulz, P. Stier, J. Fischer, L. Doppler, E. Highwood, C. Ryder, B. Harris, J. Huttunen, Y. Ma, R. T. Pinker, B. Mayer, D. Neubauer, R. Hitzenberger, L. Oreopoulos, D. Lee, G. Pitari, G. Di Genova, J. Quaas, F. G. Rose, S. Kato, S. T. Rumbold, I. Vardavas, N. Hatzianastassiou, C. Matsoukas, H. Yu, F. Zhang, H. Zhang, and P. Lu
Atmos. Chem. Phys., 13, 2347–2379, https://doi.org/10.5194/acp-13-2347-2013, https://doi.org/10.5194/acp-13-2347-2013, 2013
Related subject area
Subject: Dynamics | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
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
Technical note: Exploring parameter and meteorological uncertainty via emulation in volcanic ash atmospheric dispersion modelling
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
Potential modulation of Indian Ocean basin mode on the interdecadal variations of summer precipitation over the East Asian monsoon boundary zone
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
The influences of El Niño–Southern Oscillation on tropospheric ozone in CMIP6 models
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
Anthropogenic aerosol effects on tropospheric circulation and sea surface temperature (1980–2020): separating the role of zonally asymmetric forcings
Lightning-ignited wildfires and long continuing current lightning in the Mediterranean Basin: preferential meteorological conditions
Identifying source regions of air masses sampled at the tropical high-altitude site of Chacaltaya using WRF-FLEXPART and cluster analysis
Modelling spatiotemporal variations of the canopy layer urban heat island in Beijing at the neighbourhood scale
Dispersion of particulate matter (PM2.5) from wood combustion for residential heating: optimization of mitigation actions based on large-eddy simulations
Measurement report: Effect of wind shear on PM10 concentration vertical structure in the urban boundary layer in a complex terrain
The effect of forced change and unforced variability in heat waves, temperature extremes, and associated population risk in a CO2-warmed world
Convective self–aggregation in a mean flow
The potential for geostationary remote sensing of NO2 to improve weather prediction
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.
James M. Salter, Helen N. Webster, and Cameron Saint
EGUsphere, https://doi.org/10.5194/egusphere-2023-2870, https://doi.org/10.5194/egusphere-2023-2870, 2023
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.
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.
Jing Wang, Yanju Liu, Fei Cheng, Chengyu Song, Qiaoping Li, Yihui Ding, and Xiangde Xu
EGUsphere, https://doi.org/10.5194/egusphere-2023-1529, https://doi.org/10.5194/egusphere-2023-1529, 2023
Short summary
Short summary
Based on long-term observational, reanalysis, and numerical model simulation datasets from 1901 through 2014, this study identify that precipitation over the East Asian monsoon boundary zone featured prominent interdecadal changes, with dry summers during the periods preceding 1927, 1968–1982, and 1998–2010, and wet summers during the periods of 1928–1938, 1946–1967, and 2011 onwards. The Indian Ocean basin mode is an important oceanic modulator responsible for its interdecadal variations.
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.
Thanh Le, Seon-Ho Kim, Jae-Yeong Heo, and Deg-Hyo Bae
EGUsphere, https://doi.org/10.5194/egusphere-2023-207, https://doi.org/10.5194/egusphere-2023-207, 2023
Short summary
Short summary
We examined the links between El Niño–Southern Oscillation (ENSO) and tropospheric ozone (O3) using models’ 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 mid-latitude 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 are stronger in the upper and lower troposphere.
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.
Chenrui Diao, Yangyang Xu, and Shang-Ping Xie
Atmos. Chem. Phys., 21, 18499–18518, https://doi.org/10.5194/acp-21-18499-2021, https://doi.org/10.5194/acp-21-18499-2021, 2021
Short summary
Short summary
Anthropogenic aerosol (AA) emission has shown a zonal redistribution since the 1980s, with a decline in the Western Hemisphere (WH) high latitudes and an increase in the Eastern Hemisphere (EH) low latitudes. This study compares the role of zonally asymmetric forcings affecting the climate. The WH aerosol reduction dominates the poleward shift of the Hadley cell and the North Pacific warming, while the EH AA forcing is largely confined to the emission domain and induces local cooling responses.
Francisco J. Pérez-Invernón, Heidi Huntrieser, Sergio Soler, Francisco J. Gordillo-Vázquez, Nicolau Pineda, Javier Navarro-González, Víctor Reglero, Joan Montanyà, Oscar van der Velde, and Nikos Koutsias
Atmos. Chem. Phys., 21, 17529–17557, https://doi.org/10.5194/acp-21-17529-2021, https://doi.org/10.5194/acp-21-17529-2021, 2021
Short summary
Short summary
Lightning-ignited fires tend to occur in remote areas and can spread significantly before suppression. Long continuing current (LCC) lightning, preferably taking place in dry thunderstorms, is believed to be the main precursor of lightning-ignited fires. We analyze fire databases of lightning-ignited fires in the Mediterranean basin and report the shared meteorological conditions of fire- and LCC-lightning-producing thunderstorms. These results can be useful to improve fire forecasting methods.
Diego Aliaga, Victoria A. Sinclair, Marcos Andrade, Paulo Artaxo, Samara Carbone, Evgeny Kadantsev, Paolo Laj, Alfred Wiedensohler, Radovan Krejci, and Federico Bianchi
Atmos. Chem. Phys., 21, 16453–16477, https://doi.org/10.5194/acp-21-16453-2021, https://doi.org/10.5194/acp-21-16453-2021, 2021
Short summary
Short summary
We investigate the origin of air masses sampled at Mount Chacaltaya, Bolivia. Three-quarters of the measured air has not been influenced by the surface in the previous 4 d. However, it is rare that, at any given time, the sampled air has not been influenced at all by the surface, and often the sampled air has multiple origins. The influence of the surface is more prevalent during day than night. Furthermore, during the 6-month study, one-third of the air masses originated from Amazonia.
Michael Biggart, Jenny Stocker, Ruth M. Doherty, Oliver Wild, David Carruthers, Sue Grimmond, Yiqun Han, Pingqing Fu, and Simone Kotthaus
Atmos. Chem. Phys., 21, 13687–13711, https://doi.org/10.5194/acp-21-13687-2021, https://doi.org/10.5194/acp-21-13687-2021, 2021
Short summary
Short summary
Heat-related illnesses are of increasing concern in China given its rapid urbanisation and our ever-warming climate. We examine the relative impacts that land surface properties and anthropogenic heat have on the urban heat island (UHI) in Beijing using ADMS-Urban. Air temperature measurements and satellite-derived land surface temperatures provide valuable means of evaluating modelled spatiotemporal variations. This work provides critical information for urban planners and UHI mitigation.
Tobias Wolf, Lasse H. Pettersson, and Igor Esau
Atmos. Chem. Phys., 21, 12463–12477, https://doi.org/10.5194/acp-21-12463-2021, https://doi.org/10.5194/acp-21-12463-2021, 2021
Short summary
Short summary
House heating by wood-burning stoves is cozy and needed in boreal cities, e.g., Bergen, Norway. But smoke (aerosols) from stoves may reduce urban air quality. It can be transported over long distance excessively polluting some neighborhoods. Who will suffer the most? Our modelling study looks at urban pollution in unprecedented meter-sized details tracing smoke pathways and turbulent dispersion in a typical city. We prototype effective policy scenarios to mitigate urban air quality problems.
Piotr Sekuła, Anita Bokwa, Jakub Bartyzel, Bogdan Bochenek, Łukasz Chmura, Michał Gałkowski, and Mirosław Zimnoch
Atmos. Chem. Phys., 21, 12113–12139, https://doi.org/10.5194/acp-21-12113-2021, https://doi.org/10.5194/acp-21-12113-2021, 2021
Short summary
Short summary
The wind shear generated on a local scale by the diversified relief’s impact can be a factor which significantly modifies the spatial pattern of PM10 concentration. The vertical profile of PM10 over a city located in a large valley during the events with high surface-level PM10 concentrations may show a sudden decrease with height not only due to the increase in wind speed, but also due to the change in wind direction alone. Vertical aerosanitary urban zones can be distinguished.
Jangho Lee, Jeffrey C. Mast, and Andrew E. Dessler
Atmos. Chem. Phys., 21, 11889–11904, https://doi.org/10.5194/acp-21-11889-2021, https://doi.org/10.5194/acp-21-11889-2021, 2021
Short summary
Short summary
This paper investigates the impact of global warming on heat and humidity extremes. There are three major findings in this study. We quantify how unforced variability in the climate impacts can lead to large variations where heat waves occur, we find that all heat extremes increase as the climate warms, especially between 1.5 and 2.0 °C of the average global warming, and we show that the economic inequity of facing extreme heat will worsen in a warmer world.
Hyunju Jung, Ann Kristin Naumann, and Bjorn Stevens
Atmos. Chem. Phys., 21, 10337–10345, https://doi.org/10.5194/acp-21-10337-2021, https://doi.org/10.5194/acp-21-10337-2021, 2021
Short summary
Short summary
We analyze the behavior of organized convection in a large-scale flow by imposing a mean flow to idealized simulations. In the mean flow, organized convection initially propagates slower than the mean wind speed and becomes stationary. The initial upstream and downstream difference in surface fluxes becomes symmetric as the surface momentum flux acts as a drag, resulting in the stationarity. Meanwhile, the surface enthalpy flux has a minor role in the propagation of the convection.
Xueling Liu, Arthur P. Mizzi, Jeffrey L. Anderson, Inez Fung, and Ronald C. Cohen
Atmos. Chem. Phys., 21, 9573–9583, https://doi.org/10.5194/acp-21-9573-2021, https://doi.org/10.5194/acp-21-9573-2021, 2021
Short summary
Short summary
Observations of winds in the planetary boundary layer remain sparse, making it challenging to simulate and predict the atmospheric conditions that are most important for describing and predicting urban air quality. Here we investigate the application of data assimilation of NO2 columns as will be observed from geostationary orbit to improve predictions and retrospective analysis of wind fields in the boundary layer.
Cited articles
Allen, R. J.: A 21st century northward tropical precipitation
shift caused by future anthropogenic aerosol reductions, J. Geophys. Res.-Atmos, 120, 9087–9102,
https://doi.org/10.1002/2015JD023623, 2015. a, b
Allen, R. J. and Luptowitz, R.: El Niño-like
teleconnection increases California precipitation in response to warming, Nat. Commun., 8, 16055,
https://doi.org/10.1038/ncomms16055, 2017. a
Allen, R. J., Evan, A. T., and Booth,
B. B. B.: Interhemispheric Aerosol Radiative Forcing and Tropical Precipitation Shifts during the
Late Twentieth Century, J. Climate, 28, 8219–8246, https://doi.org/10.1175/JCLI-D-15-0148.1, 2015. a
Bakker, P.,
Schmittner, A., Lenaerts, J. T. M., Abe-Ouchi, A., Bi, D., van den Broeke, M. R., Chan, W.-L., Hu,
A., Beadling, R. L., Marsland, S. J., Mernild, S. H., Saenko, O. A., Swingedouw, D., Sullivan, A.,
and Yin, J.: Fate of the Atlantic Meridional Overturning Circulation: Strong decline under
continued warming and Greenland melting, Geophys. Res. Lett., 43, 12252–12260, https://doi.org/10.1002/2016GL070457, 2016. a
Bellomo, K.,
Murphy, L. N., Cane, M. A., Clement, A. C., and Polvani, L. M.: Historical forcings as main
drivers of the Atlantic multidecadal variability in the CESM large ensemble, Clim. Dynam., 50,
3687–3698, https://doi.org/10.1007/s00382-017-3834-3, 2018. a
Bellouin, N., Quaas, J., Gryspeerdt, E., Kinne, S., Stier, P., Watson-Parris, D., Boucher, O., Carslaw, K., Christensen, M., Daniau, A.-L., and Dufresne, J. : Bounding global aerosol radiative forcing of climate change, Rev. Geophys., 58, e2019RG000660, 2020. a
Booth,
B. B. B., Dunstone, N. J., Halloran, P. R., Andrews, T., and Bellouin, N.: Aerosols implicated as
a prime driver of twentieth-century North Atlantic climate variability, Nature, 484, 228–232,
https://doi.org/10.1038/nature10946, 2012. a
Broecker, W. S.: Thermohaline Circulation, the Achilles Heel
of Our Climate System: Will Man-Made CO2 Upset the Current Balance?, Science, 278,
1582–1588, https://doi.org/10.1126/science.278.5343.1582, 1997. a
Buckley, M. W. and Marshall, J.: Observations,
inferences, and mechanisms of the Atlantic Meridional Overturning Circulation: A review,
Rev. Geophys., 54, 5–63, https://doi.org/10.1002/2015RG000493, 2016. a
Caesar, L.,
Rahmstorf, S., Robinson, A., Feulner, G., and Saba, V.: Observed fingerprint of a weakening
Atlantic Ocean overturning circulation, Nature, 556, 191–196, https://doi.org/10.1038/s41586-018-0006-5,
2018. a, b, c
Cai, W., Bi, D.,
Church, J., Cowan, T., Dix, M., and Rotstayn, L.: Pan-oceanic response to increasing anthropogenic
aerosols: Impacts on the Southern Hemisphere oceanic circulation, Geophys. Res. Lett., 33, L21707,
https://doi.org/10.1029/2006GL027513, 2006. a, b
Cai, W.,
Cowan, T., Dix, M., Rotstayn, L., Ribbe, J., Shi, G., and Wijffels, S.: Anthropogenic aerosol
forcing and the structure of temperature trends in the southern Indian Ocean, Geophys. Res. Lett.,
34, L14611, https://doi.org/10.1029/2007GL030380, 2007. a, b
Cessi, P., Bryan, K., and Zhang, R.:
Global seiching of thermocline waters between the Atlantic and the Indian-Pacific Ocean Basins,
Geophys. Res. Lett., 31, 4, https://doi.org/10.1029/2003GL019091, 2004. a
Chang, C.-Y.,
Chiang, J. C. H., Wehner, M. F., Friedman, A. R., and Ruedy, R.: Sulfate Aerosol Control of
Tropical Atlantic Climate over the Twentieth Century, J. Climate, 24, 2540–2555,
https://doi.org/10.1175/2010JCLI4065.1, 2011. a
Chang, E. K. M.,
Zheng, C., Lanigan, P., Yau, A. M. W., and Neelin, J. D.: Significant modulation of variability
and projected change in California winter precipitation by extratropical cyclone activity,
Geophys. Res. Lett., 42, 5983–5991, https://doi.org/10.1002/2015GL064424, 2015. a
Chen, X. and Tung, K.-K.: Global surface warming
enhanced by weak Atlantic overturning circulation, Nature, 559, 387–391, 2018. a
Cheng, W., Chiang, J. C. H., and
Zhang, D.: Atlantic Meridional Overturning Circulation (AMOC) in CMIP5 Models: RCP and Historical
Simulations, J. Climate, 26, 7187–7197, https://doi.org/10.1175/JCLI-D-12-00496.1, 2013. a, b, c
Collier,
M. A., Rotstayn, L. D., Kim, K.-Y., Hirst, A. C., and Jeffrey, S. J.: Ocean circulation response
to anthropogenicaerosol and greenhouse gas forcing in the CSIRO-Mk3.6 coupled climate model,
Australian Meteorol. Ocean., 63, 27–39, https://doi.org/10.22499/2.6301.003, 2013. a, b
Cowan, T. and Cai, W.: The response of the large-scale
ocean circulation to 20th century Asian and non-Asian aerosols, Geophys. Res. Lett., 40,
2761–2767, https://doi.org/10.1002/grl.50587, 2013. a, b
Danabasoglu, G., Yeager, S. G., Bailey, D., Behrens, E., Bentsen, M., Bi, D., Biastoch, A., Böning, C., Bozec, A., Canuto, V. M., Cassou, C., Chassignet, E., Coward, A. C., Danilov, S., Diansky, N., Drange, H., Farneti, R., Fernandez, E., Fogli, P. G., Forget, G., Fujii, Y., Griffies, S. M., Gusev, A., Heimbach, P., Howard, A., Jung, T., Kelley, M., Large, W. G., Leboissetier, A., Lu, J., Madec, G., Marsland, S. J., Masina, S., Navarra, A., Nurser, A. G., Pirani, A., Salas y Mélia, D., Samuels, B. L., Scheinert, M., Sidorenko, D., Treguier, A.-M., Tsujino, H., Uotila, P., Valcke, S., Voldoire, A., and Wang, Q.: North Atlantic simulations in Coordinated Ocean-ice Reference Experiments phase II (CORE-II), Part I: Mean states, Ocean Model., 73, 76–107, https://doi.org/10.1016/j.ocemod.2013.10.005, 2014. a
Danabasoglu, G., Yeager, S. G., Kim, W. M., Behrens, E.,
Bentsen, M., Bi, D., Biastoch, A., Bleck, R., Böning, C., Bozec, A., Canuto, V. M., Cassou,
C., Chassignet, E., Coward, A. C., Danilov, S., Diansky, N., Drange, H., Farneti, R., Fernandez,
E., Fogli, P. G., Forget, G., Fujii, Y., Griffies, S. M., Gusev, A., Heimbach, P., Howard, A.,
Ilicak, M., Jung, T., Karspeck, A. R., Kelley, M., Large, W. G., Leboissetier, A., Lu, J., Madec,
G., Marsland, S. J., Masina, S., Navarra, A., Nurser, A. G., Pirani, A., Romanou, A., y Mélia,
D. S., Samuels, B. L., Scheinert, M., Sidorenko, D., Sun, S., Treguier, A.-M., Tsujino, H.,
Uotila, P., Valcke, S., Voldoire, A., Wang, Q., and Yashayaev, I.: North Atlantic simulations in
Coordinated Ocean-ice Reference Experiments phase II (CORE-II). Part II: Inter-annual to decadal
variability, Ocean Model., 97, 65–90, https://doi.org/10.1016/j.ocemod.2015.11.007, 2016. a
Delworth, T. L. and Dixon, K. W.: Have
anthropogenic aerosols delayed a greenhouse gas-induced weakening of the North Atlantic
thermohaline circulation?, Geophys. Res. Lett., 33, L02606, https://doi.org/10.1029/2005GL024980, 2006. a, b
Delworth, T. L. and Mann, M. E.: Observed and
simulated multidecadal variability in the Northern Hemisphere, Clim. Dynam., 16, 661–676,
https://doi.org/10.1007/s003820000075, 2000. a
Drijfhout,
S., van Oldenborgh, G. J., and Cimatoribus, A.: Is a Decline of AMOC Causing the Warming Hole
above the North Atlantic in Observed and Modeled Warming Patterns?, J. Climate, 25, 8373–8379,
https://doi.org/10.1175/JCLI-D-12-00490.1, 2012. a
Drijfhout, S. S. and Hazeleger, W.: Detecting
Atlantic MOC Changes in an Ensemble of Climate Change Simulations, J. Climate, 20, 1571–1582,
https://doi.org/10.1175/JCLI4104.1, 2007. a
Drijfhout,
S. S., Weber, S. L., and van der Swaluw, E.: The stability of the MOC as diagnosed from model
projections for pre-industrial, present and future climates, Clim. Dynam., 37, 1575–1586,
https://doi.org/10.1007/s00382-010-0930-z, 2011. a
ECMWF: ERA5, available at: https://www.ecmwf.int/en/forecasts/datasets/reanalysis-datasets/era5, last access: 14 April 2021. a
Eden, C. and Jung, T.: North Atlantic Interdecadal
Variability: Oceanic Response to the North Atlantic Oscillation (1865–1997), J. Climate, 14,
676–691, https://doi.org/10.1175/1520-0442(2001)014<0676:NAIVOR>2.0.CO;2, 2001. a
ESGF (Earth System Grid Federation) – LLNL: Coupled Model Intercomparison Project Phase 6, available at: https://esgf-node.llnl.gov/search/cmip6/, last access: 14 April 2021. a
Evan, A. T.,
Vimont, D. J., Heidinger, A. K., Kossin, J. P., and Bennartz, R.: The role of aerosols in the
evolution of tropical North Atlantic Ocean temperature anomalies, Science, 324, 778–781, 2009. a
Eyring, V., Bony, S., Meehl, G. A., Senior, C. A., Stevens, B., Stouffer, R. J., and Taylor,
K. E.: Overview of the Coupled Model Intercomparison Project Phase 6 (CMIP6) experimental design
and organization, Geosci. Model Dev., 9, 1937–1958, https://doi.org/10.5194/gmd-9-1937-2016, 2016. a
Fofonoff, N. P. and Millard Jr.,
R.: Algorithms for the computation of fundamental properties of seawater, 44, 53 pp., 1983. a
Forster, P. M., Richardson, T., Maycock, A. C., Smith, C. J., Samset,
B. H., Myhre, G., Andrews, T., Pincus, R., and Schulz, M.: Recommendations for diagnosing
effective radiative forcing from climate models for CMIP6, J. Geophys. Res.-Atmos, 121,
12,460–12,475, https://doi.org/10.1002/2016JD025320, 2016. a
Frajka-Williams, E.,
Ansorge, I. J., Baehr, J., Bryden, H. L., Chidichimo, M. P., Cunningham, S. A., Danabasoglu, G.,
Dong, S., Donohue, K. A., Elipot, S., Heimbach, P., Holliday, N. P., Hummels, R., Jackson, L. C.,
Karstensen, J., Lankhorst, M., Le Bras, I. A., Lozier, M. S., McDonagh, E. L., Meinen, C. S.,
Mercier, H., Moat, B. I., Perez, R. C., Piecuch, C. G., Rhein, M., Srokosz, M. A., Trenberth,
K. E., Bacon, S., Forget, G., Goni, G., Kieke, D., Koelling, J., Lamont, T., McCarthy, G. D.,
Mertens, C., Send, U., Smeed, D. A., Speich, S., van den Berg, M., Volkov, D., and Wilson, C.:
Atlantic Meridional Overturning Circulation: Observed Transport and Variability,
Front. Mar. Sci., 6, 260, https://doi.org/10.3389/fmars.2019.00260, 2019. a
Grachev, A. A. and Fairall, C. W.: Dependence of
the Monin–Obukhov Stability Parameter on the Bulk Richardson Number over the Ocean,
J. Appl. Meteorol., 36, 406–414, https://doi.org/10.1175/1520-0450(1997)036<0406:DOTMOS>2.0.CO;2, 1997. a
Gregory, J. M., Dixon, K. W., Stouffer, R. J., Weaver, A. J., Driesschaert,
E., Eby, M., Fichefet, T., Hasumi, H., Hu, A., Jungclaus, J. H., Kamenkovich, I. V., Levermann,
A., Montoya, M., Murakami, S., Nawrath, S., Oka, A., Sokolov, A. P., and Thorpe, R. B.: A model
intercomparison of changes in the Atlantic thermohaline circulation in response to increasing
atmospheric CO2 concentration, Geophys. Res. Lett., 32, 12, https://doi.org/10.1029/2005GL023209, 2005. a
Hassan, T.: acccmip6, available at: https://github.com/TaufiqHassan/acccmip6, last access: 14 April 2021. a
Hoesly, R. M., Smith, S. J., Feng, L., Klimont, Z., Janssens-Maenhout, G.,
Pitkanen, T., Seibert, J. J., Vu, L., Andres, R. J., Bolt, R. M., Bond, T. C., Dawidowski, L.,
Kholod, N., Kurokawa, J.-I., Li, M., Liu, L., Lu, Z., Moura, M. C. P., O'Rourke, P. R., and Zhang,
Q.: Historical (1750–2014) anthropogenic emissions of reactive gases and aerosols from the
Community Emissions Data System (CEDS), Geosci. Model Dev., 11, 369–408,
https://doi.org/10.5194/gmd-11-369-2018, 2018. a
Hu, S. and Fedorov, A. V.: Indian Ocean warming can
strengthen the Atlantic meridional overturning circulation, Nat. Clim. Change, 9, 747–751,
https://doi.org/10.1038/s41558-019-0566-x, 2019. a
Huang, R. X., Cane, M. A.,
Naik, N., and Goodman, P.: Global adjustment of the thermocline in response to deepwater
formation, Geophys. Res. Lett., 27, 759–762, https://doi.org/10.1029/1999GL002365, 2000. a
Jackson, L. C.,
Peterson, K. A., Roberts, C. D., and Wood, R. A.: Recent slowing of Atlantic overturning
circulation as a recovery from earlier strengthening, Nat. Geosci., 9, 518–522,
https://doi.org/10.1038/ngeo2715, 2016. a
Johnson, H. L. and Marshall, D. P.: A Theory for
the Surface Atlantic Response to Thermohaline Variability, J. Phys. Oceanogr., 32, 1121–1132,
https://doi.org/10.1175/1520-0485(2002)032<1121:ATFTSA>2.0.CO;2, 2002. a
Kawase, M.: Establishment of Deep Ocean Circulation Driven by
Deep-Water Production, J. Phys. Oceanogr., 17, 2294–2317,
https://doi.org/10.1175/1520-0485(1987)017<2294:EODOCD>2.0.CO;2, 1987. a
Keil, P., Mauritsen, T., Jungclaus, J., Hedemann, C., Olonscheck, D.,
and Ghosh, R.: Multiple drivers of the North Atlantic warming hole, Nat. Clim. Change, 10, 667–671, 2020. a
Kirtman, B., Power, S., Adedoyin, J., Boer, G., Bojariu, R., Camilloni, I., Doblas-Reyes, F., Fiore, A., Kimoto, M., Meehl, G., Prather, M., Sarr, A., Schär, C., Sutton, R., van Oldenborgh, G., Vecchi, G., and Wan, H.:
Near-term Climate Change: Projections and Predictability,
in: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change,
edited by: Stocker, T. F., Qin, D., Plattner, G.-K., Tignor, M., Allen, S. K., Boschung, J., Nauels, A., Xia, Y., Bex, V., and Midgley, P. M.,
Tech. rep.,
Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 953–1028, 2013. a
Klein, S. A. and Hartmann, D. L.: The seasonal cycle
of low stratiform clouds, J. Climate, 6, 1587–1606, 1993. a
Knight, J. R.,
Allan, R. J., Folland, C. K., Vellinga, M., and Mann, M. E.: A signature of persistent natural
thermohaline circulation cycles in observed climate, Geophys. Res. Lett., 32, L20708,
https://doi.org/10.1029/2005GL024233, 2005. a
Kostov, Y., Armour, K. C., and
Marshall, J.: Impact of the Atlantic meridional overturning circulation on ocean heat storage and
transient climate change, Geophys. Res. Lett., 41, 2108–2116, https://doi.org/10.1002/2013GL058998, 2014. a, b, c
Levitus, S., Antonov, J. I., Boyer, T. P.,
Baranova, O. K., Garcia, H. E., Locarnini, R. A., Mishonov, A. V., Reagan, J. R., Seidov, D.,
Yarosh, E. S., and Zweng, M. M.: World ocean heat content and thermosteric sea level change
(0–2000 m), 1955–2010, Geophys. Res. Lett., 39, 10, https://doi.org/10.1029/2012GL051106, 2012. a
Liu, W. and Liu, Z.: A diagnostic indicator of the
stability of the Atlantic meridional overturning circulation in CCSM3, J. Climate, 26, 1926–1938,
2013. a
Liu, W., Xie, S.-P., Liu, Z., and Zhu, J.:
Overlooked possibility of a collapsed Atlantic Meridional Overturning Circulation in warming
climate, Sci. Adv., 3, 1, https://doi.org/10.1126/sciadv.1601666, 2017. a, b, c
Liu, W., Fedorov, A., and
Sévellec, F.: The Mechanisms of the Atlantic Meridional Overturning Circulation Slowdown
Induced by Arctic Sea Ice Decline, J. Climate, 32, 977–996, https://doi.org/10.1175/JCLI-D-18-0231.1, 2019. a, b, c
Liu, W., Fedorov, A. V., Xie, S.-P.,
and Hu, S.: Climate impacts of a weakened Atlantic Meridional Overturning Circulation in a warming
climate, Sci. Adv., 6, 26,
https://doi.org/10.1126/sciadv.aaz4876, 2020. a
Ma, X., Liu, W., Allen,
R. J., Huang, G., and Li, X.: Dependence of regional ocean heat uptake on anthropogenic warming
scenarios, Sci. Adv., 6, eabc0303, 2020. a
Maronga, B.: Monin–Obukhov Similarity Functions for the
Structure Parameters of Temperature and Humidity in the Unstable Surface Layer: Results from
High-Resolution Large-Eddy Simulations, J. Atmos. Sci., 71, 716–733,
https://doi.org/10.1175/JAS-D-13-0135.1, 2014. a
Marshall, J.,
Donohoe, A., Ferreira, D., and McGee, D.: The ocean's role in setting the mean position of the
Inter-Tropical Convergence Zone, Clim. Dynam., 42, 1967–1979, https://doi.org/10.1007/s00382-013-1767-z,
2014. a
Marshall, J., Scott, J. R., Armour, K. C., Campin, J. M., Kelley, M., and Romanou, A.: The ocean's
role in the transient response of climate to abrupt greenhouse gas forcing, Clim. Dynam., 44,
2287–2299, https://doi.org/10.1007/s00382-014-2308-0, 2015. a
McCarthy, G., Frajka-Williams, E., Johns, W. E.,
Baringer, M. O., Meinen, C. S., Bryden, H. L., Rayner, D., Duchez, A., Roberts, C., and
Cunningham, S. A.: Observed interannual variability of the Atlantic meridional overturning
circulation at 26.5∘ N, Geophys. Res. Lett., 39, L19609, https://doi.org/10.1029/2012GL052933,
2012. a
Meehl, G. A., Senior, C. A., Eyring, V., Flato, G., Lamarque, J.-F.,
Stouffer, R. J., Taylor, K. E., and Schlund, M.: Context for interpreting equilibrium climate
sensitivity and transient climate response from the CMIP6 Earth system models, Sci. Adv., 6,
eaba1981, 2020. a
Menary, M. B., Roberts, C. D., Palmer, M. D., Halloran, P. R., Jackson, L.,
Wood, R. A., Müller, W. A., Matei, D., and Lee, S.-K.: Mechanisms of aerosol-forced AMOC
variability in a state of the art climate model, J. Geophys. Res.-Oceans, 118, 2087–2096,
https://doi.org/10.1002/jgrc.20178, 2013. a, b, c, d
Menary, M. B., Robson, J., Allan,
R. P., Booth, B. B. B., Cassou, C., Gastineau, G., Gregory, J., Hodson, D., Jones, C., Mignot, J.,
Ringer, M., Sutton, R., Wilcox, L., and Zhang, R.: Aerosol-Forced AMOC Changes in CMIP6 Historical
Simulations, Geophys. Res. Lett., 47, e2020GL088166, https://doi.org/10.1029/2020GL088166, 2020. a, b, c, d
Murphy, L. N., Bellomo,
K., Cane, M., and Clement, A.: The role of historical forcings in simulating the observed Atlantic
multidecadal oscillation, Geophys. Res. Lett., 44, 2472–2480, https://doi.org/10.1002/2016GL071337, 2017. a
National Aeronautics and Space Administration: Modern-Era Retrospective analysis for Research and Applications, version2, available at: https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/, last access: 14 April 2021. a
National Center for Atmospheric Research: NCEP/NCAR Reanalysis, available at: https://psl.noaa.gov/data/gridded/data.ncep.reanalysis.html, last access: 14 April 2021. a
National Oceanography Centre: RAPID, available at: https://rapid.ac.uk/rapidmoc/rapid_data/datadl.php, last access: 14 April 2021. a
NCEI-NOAA: Global Ocean Heat and Salt Content, available at: https://www.ncei.noaa.gov/access/global-ocean-heat-content/,
last access: 14 April 2021. a
NOAA-PSL: GISS Surface Temperature Analysis, available at: https://psl.noaa.gov/data/gridded/data.gistemp.html,
last access: 14 April 2021a. a
NOAA-PSL: Jones (CRU) Air Temperature Anomalies Version 4: CRUTEM4, available at: https://psl.noaa.gov/data/gridded/data.crutem4.html#detail, last access: 14 April 2021b. a
NOAA-PSL: NOAA Global Surface Temperature (NOAAGlobalTemp), available at: https://psl.noaa.gov/data/gridded/data.noaaglobaltemp.html,
last access: 14 April 2021. a
O'Neill, B. C., Kriegler, E., Riahi, K., Ebi, K. L., Hallegatte, S., Carter,
T. R., Mathur, R., and van Vuuren, D. P.: A new scenario framework for climate change research:
the concept of shared socioeconomic pathways, Climatic Change, 122, 387–400,
https://doi.org/10.1007/s10584-013-0905-2, 2014. a
Otterå, O. H.,
Bentsen, M., Drange, H., and Suo, L.: External forcing as a metronome for Atlantic multidecadal
variability, Nat. Geosci., 3, 688–694, https://doi.org/10.1038/ngeo955, 2010. a
Palmer, M. D. and McNeall, D. J.: Internal
variability of Earth's energy budget simulated by CMIP5 climate models, Environ. Res. Lett., 9,
034016, https://doi.org/10.1088/1748-9326/9/3/034016, 2014. a
Rahmstorf, S.: On the freshwater forcing and transport of
the Atlantic thermohaline circulation, Clim. Dynam., 12, 799–811, https://doi.org/10.1007/s003820050144,
1996. a
Rahmstorf, S., Box, J. E., Feulner, G., Mann, M. E., Robinson, A.,
Rutherford, S., and Schaffernicht, E. J.: Exceptional twentieth-century slowdown in Atlantic Ocean
overturning circulation, Nat. Clim. Change, 5, 475–480, https://doi.org/10.1038/nclimate2554, 2015. a, b, c, d
Sévellec, F.,
Fedorov, A. V., and Liu, W.: Arctic sea-ice decline weakens the Atlantic Meridional Overturning
Circulation, Nat. Clim. Change, 7, 604–610, https://doi.org/10.1038/nclimate3353, 2017. a, b
Smeed, D. A., McCarthy, G. D., Cunningham, S. A.,
Frajka-Williams, E., Rayner, D., Johns, W. E., Meinen, C. S., Baringer, M. O., Moat, B. I.,
Duchez, A., and Bryden, H. L.: Observed decline of the Atlantic meridional overturning circulation
2004–2012, Ocean Sci., 10, 29–38, https://doi.org/10.5194/os-10-29-2014, 2014. a
Smeed, D. A., Josey, S. A., Beaulieu, C., Johns,
W. E., Moat, B. I., Frajka-Williams, E., Rayner, D., Meinen, C. S., Baringer, M. O., Bryden,
H. L., and McCarthy, G. D.: The North Atlantic Ocean Is in a State of Reduced Overturning,
Geophys. Res. Lett., 45, 1527–1533, https://doi.org/10.1002/2017GL076350, 2018. a
Smith, C. J., Kramer, R. J., Myhre, G.,
Alterskjær, K., Collins, W., Sima, A., Boucher, O., Dufresne, J.-L., Nabat, P., Michou, M.,
Yukimoto, S., Cole, J., Paynter, D., Shiogama, H., O'Connor, F. M., Robertson, E., Wiltshire, A.,
Andrews, T., Hannay, C., Miller, R., Nazarenko, L., Kirkevåg, A., Olivié, D., Fiedler, S.,
Lewinschal, A., Mackallah, C., Dix, M., Pincus, R., and Forster, P. M.: Effective radiative
forcing and adjustments in CMIP6 models, Atmos. Chem. Phys., 20, 9591–9618,
https://doi.org/10.5194/acp-20-9591-2020, 2020. a
Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K. B., Tignor, M., and Miller, H. L. (Eds.):
Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change,
Cambridge University Press, New York, pp. 996, 2007. a
Talley, L. D.: Freshwater transport estimates and the global
overturning circulation: Shallow, deep and throughflow components, Prog. Oceanogr., 78, 257–303,
https://doi.org/10.1016/j.pocean.2008.05.001, 2008. a
Thorpe, R., Gregory, J. M., Johns, T., Wood, R., and Mitchell, J.: Mechanisms determining the
Atlantic thermohaline circulation response to greenhouse gas forcing in a non-flux-adjusted
coupled climate model, J. Climate, 14, 3102–3116, 2001. a
Toll, V.,
Christensen, M., Quaas, J., and Bellouin, N.: Weak average liquid-cloud-water response to
anthropogenic aerosols, Nature, 572, 51–55, 2019. a
Weijer, W.,
Cheng, W., Garuba, O., Hu, A., and Nadiga, B.: CMIP6 models predict significant 21st century
decline of the Atlantic Meridional Overturning Circulation, Geophys. Res. Lett., 47, e2019GL086075, 2020. a
Winton, M., Griffies, S. M., Samuels, B. L., Sarmiento, J. L., and Frölicher, T. L.:
Connecting Changing Ocean Circulation with Changing Climate, J. Climate, 26, 2268–2278,
https://doi.org/10.1175/JCLI-D-12-00296.1, 2013. a
Woods Hole Oceanographic Institution: WHOI OAFlux Project, available at: http://oaflux.whoi.edu/, last access: 14 April 2021. a
Yan, X., Zhang, R., and Knutson, T. R.:
Underestimated AMOC Variability and Implications for AMV and Predictability in CMIP Models,
Geophys. Res. Lett., 45, 4319–4328, https://doi.org/10.1029/2018GL077378, 2018. a
Zhang, R.: Latitudinal dependence of Atlantic meridional
overturning circulation (AMOC) variations, Geophys. Res. Lett., 37, 16, https://doi.org/10.1029/2010GL044474, 2010. a
Zhang, R., Delworth, T. L., Sutton, R.,
Hodson, D. L. R., Dixon, K. W., Held, I. M., Kushnir, Y., Marshall, J., Ming, Y., Msadek, R.,
Robson, J., Rosati, A. J., Ting, M., and Vecchi, G. A.: Have Aerosols Caused the Observed Atlantic
Multidecadal Variability?, J. Atmos. Sci., 70, 1135–1144, https://doi.org/10.1175/JAS-D-12-0331.1, 2013. a, b, c
Zhao, J. and Johns, W.: Wind-forced interannual variability
of the Atlantic Meridional Overturning Circulation at 26.5∘ N, J. Geophys. Res.-Oceans,
119, 2403–2419, https://doi.org/10.1002/2013JC009407, 2014. a
Zhu, C. and Liu, Z.: Weakening Atlantic overturning
circulation causes South Atlantic salinity pile-up, Nat. Clim. Change, 10, 998–1003, 2020. a
Short summary
State-of-the-art climate models yield robust, externally forced changes in the Atlantic meridional overturning circulation (AMOC), the bulk of which are due to anthropogenic aerosol perturbations to net surface shortwave radiation and sea surface temperature. AMOC-related feedbacks act to reinforce this aerosol-forced response, largely due to changes in sea surface salinity (and hence sea surface density), with temperature- and cloud-related feedbacks acting to mute the initial response.
State-of-the-art climate models yield robust, externally forced changes in the Atlantic...
Altmetrics
Final-revised paper
Preprint