Articles | Volume 16, issue 5
https://doi.org/10.5194/acp-16-3383-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue:
https://doi.org/10.5194/acp-16-3383-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
15 Mar 2016
Research article |
| 15 Mar 2016
Convective sources of trajectories traversing the tropical tropopause layer
Ann-Sophie Tissier
CORRESPONDING AUTHOR
Laboratoire de Météorologie Dynamique, UPMC Paris 06/CNRS/ENS/Ecole
Polytechnique, UMR 8539, Paris, France
Bernard Legras
Laboratoire de Météorologie Dynamique, UPMC Paris 06/CNRS/ENS/Ecole
Polytechnique, UMR 8539, Paris, France
Related authors
No articles found.
Bernard Legras, Clair Duchamp, Pasquale Sellitto, Aurélien Podglajen, Elisa Carboni, Richard Siddans, Jens-Uwe Grooß, Sergey Khaykin, and Felix Ploeger
Atmos. Chem. Phys., 22, 14957–14970, https://doi.org/10.5194/acp-22-14957-2022, https://doi.org/10.5194/acp-22-14957-2022, 2022
Short summary
Short summary
The long-duration atmospheric impact of the Tonga eruption in January 2022 is a plume of water and sulfate aerosols in the stratosphere that persisted for more than 6 months. We study this evolution using several satellite instruments and analyse the unusual behaviour of this plume as sulfates and water first moved down rapidly and then separated into two layers. We also report the self-organization in compact and long-lived patches.
Pasquale Sellitto, Redha Belhadji, Corinna Kloss, and Bernard Legras
Atmos. Chem. Phys., 22, 9299–9311, https://doi.org/10.5194/acp-22-9299-2022, https://doi.org/10.5194/acp-22-9299-2022, 2022
Short summary
Short summary
As a consequence of extreme heat and drought, record-breaking wildfires ravaged south-eastern Australia during the fire season in 2019–2020. Fires injected a smoke plume very high up to the stratosphere, which dispersed quite quickly to the whole Southern Hemisphere and interacted with solar radiation, reflecting and absorbing part of it – thus producing impacts on the climate system. Here we estimate this impact on radiation and we study how it depends on the properties and ageing of the plume.
Sergey M. Khaykin, Elizabeth Moyer, Martina Krämer, Benjamin Clouser, Silvia Bucci, Bernard Legras, Alexey Lykov, Armin Afchine, Francesco Cairo, Ivan Formanyuk, Valentin Mitev, Renaud Matthey, Christian Rolf, Clare E. Singer, Nicole Spelten, Vasiliy Volkov, Vladimir Yushkov, and Fred Stroh
Atmos. Chem. Phys., 22, 3169–3189, https://doi.org/10.5194/acp-22-3169-2022, https://doi.org/10.5194/acp-22-3169-2022, 2022
Short summary
Short summary
The Asian monsoon anticyclone is the key contributor to the global annual maximum in lower stratospheric water vapour. We investigate the impact of deep convection on the lower stratospheric water using a unique set of observations aboard the high-altitude M55-Geophysica aircraft deployed in Nepal in summer 2017 within the EU StratoClim project. We find that convective plumes of wet air can persist within the Asian anticyclone for weeks, thereby enhancing the occurrence of high-level clouds.
Ralf Weigel, Christoph Mahnke, Manuel Baumgartner, Antonis Dragoneas, Bärbel Vogel, Felix Ploeger, Silvia Viciani, Francesco D'Amato, Silvia Bucci, Bernard Legras, Beiping Luo, and Stephan Borrmann
Atmos. Chem. Phys., 21, 11689–11722, https://doi.org/10.5194/acp-21-11689-2021, https://doi.org/10.5194/acp-21-11689-2021, 2021
Short summary
Short summary
In July and August 2017, eight StratoClim mission flights of the Geophysica reached up to 20 km in the Asian monsoon anticyclone. New particle formation (NPF) was identified in situ by abundant nucleation-mode aerosols (6–15 nm in diameter) with mixing ratios of up to 50 000 mg−1. NPF occurred most frequently at 12–16 km with fractions of non-volatile residues of down to 15 %. Abundance and productivity of observed NPF indicate its ability to promote the Asian tropopause aerosol layer.
Felix Ploeger, Mohamadou Diallo, Edward Charlesworth, Paul Konopka, Bernard Legras, Johannes C. Laube, Jens-Uwe Grooß, Gebhard Günther, Andreas Engel, and Martin Riese
Atmos. Chem. Phys., 21, 8393–8412, https://doi.org/10.5194/acp-21-8393-2021, https://doi.org/10.5194/acp-21-8393-2021, 2021
Short summary
Short summary
We investigate the global stratospheric circulation (Brewer–Dobson circulation) in the new ECMWF ERA5 reanalysis based on age of air simulations, and we compare it to results from the preceding ERA-Interim reanalysis. Our results show a slower stratospheric circulation and higher age for ERA5. The age of air trend in ERA5 over the 1989–2018 period is negative throughout the stratosphere, related to multi-annual variability and a potential contribution from changes in the reanalysis system.
Francesco Cairo, Mauro De Muro, Marcel Snels, Luca Di Liberto, Silvia Bucci, Bernard Legras, Ajil Kottayil, Andrea Scoccione, and Stefano Ghisu
Atmos. Chem. Phys., 21, 7947–7961, https://doi.org/10.5194/acp-21-7947-2021, https://doi.org/10.5194/acp-21-7947-2021, 2021
Short summary
Short summary
A lidar was used in Palau from February–March 2016. Clouds were observed peaking at 3 km below the high cold-point tropopause (CPT). Their occurrence was linked with cold anomalies, while in warm cases, cirrus clouds were restricted to 5 km below the CPT. Thin subvisible cirrus (SVC) near the CPT had distinctive characteristics. They were linked to wave-induced cold anomalies. Back trajectories are mostly compatible with convective outflow, while some distinctive SVC may originate in situ.
Hugo Lestrelin, Bernard Legras, Aurélien Podglajen, and Mikail Salihoglu
Atmos. Chem. Phys., 21, 7113–7134, https://doi.org/10.5194/acp-21-7113-2021, https://doi.org/10.5194/acp-21-7113-2021, 2021
Short summary
Short summary
Following the 2020 Australian fires, it was recently discovered that stratospheric wildfire smoke plumes self-organize as anticyclonic vortices that persist for months and rise by 10 km due to the radiative heating from the absorbing smoke. In this study, we show that smoke-charged vortices previously occurred in the aftermath of the 2017 Canadian fires. We use meteorological analysis to characterize this new object in geophysical fluid dynamics, which likely impacts radiation and climate.
Keun-Ok Lee, Brice Barret, Eric L. Flochmoën, Pierre Tulet, Silvia Bucci, Marc von Hobe, Corinna Kloss, Bernard Legras, Maud Leriche, Bastien Sauvage, Fabrizio Ravegnani, and Alexey Ulanovsky
Atmos. Chem. Phys., 21, 3255–3274, https://doi.org/10.5194/acp-21-3255-2021, https://doi.org/10.5194/acp-21-3255-2021, 2021
Short summary
Short summary
This paper focuses on the emission sources and pathways of pollution from the boundary layer to the Asian monsoon anticyclone (AMA) during the StratoClim aircraft campaign period. Simulations with the Meso-NH cloud-chemistry model at a horizontal resolution of 15 km are performed over the Asian region to characterize the impact of monsoon deep convection on the composition of AMA and on the formation of the Asian tropopause aerosol layer during the StratoClim campaign.
Adriana Bossolasco, Fabrice Jegou, Pasquale Sellitto, Gwenaël Berthet, Corinna Kloss, and Bernard Legras
Atmos. Chem. Phys., 21, 2745–2764, https://doi.org/10.5194/acp-21-2745-2021, https://doi.org/10.5194/acp-21-2745-2021, 2021
Short summary
Short summary
Using the Community Earth System Model, we simulate the surface aerosols lifted to the Asian tropopause (the ATAL layer), its composition and trend, covering a long-term period (2000–2015). We identify a
double-peakaerosol vertical profile that we attribute to
dryand
convectivecloud-borne aerosols. We find that natural aerosol (mineral dust) is the dominant aerosol type and has no long-term trend. ATAL's anthropogenic fraction, by contrast, shows a marked positive trend.
Corinna Kloss, Gwenaël Berthet, Pasquale Sellitto, Felix Ploeger, Ghassan Taha, Mariam Tidiga, Maxim Eremenko, Adriana Bossolasco, Fabrice Jégou, Jean-Baptiste Renard, and Bernard Legras
Atmos. Chem. Phys., 21, 535–560, https://doi.org/10.5194/acp-21-535-2021, https://doi.org/10.5194/acp-21-535-2021, 2021
Short summary
Short summary
The year 2019 was particularly rich for the stratospheric aerosol layer due to two volcanic eruptions (at Raikoke and Ulawun) and wildfire events. With satellite observations and models, we describe the exceptionally complex situation following the Raikoke eruption. The respective plume overwhelmed the Northern Hemisphere stratosphere in terms of aerosol load and resulted in the highest climate impact throughout the past decade.
Sören Johansson, Michael Höpfner, Oliver Kirner, Ingo Wohltmann, Silvia Bucci, Bernard Legras, Felix Friedl-Vallon, Norbert Glatthor, Erik Kretschmer, Jörn Ungermann, and Gerald Wetzel
Atmos. Chem. Phys., 20, 14695–14715, https://doi.org/10.5194/acp-20-14695-2020, https://doi.org/10.5194/acp-20-14695-2020, 2020
Short summary
Short summary
We present high-resolution measurements of pollutant trace gases (PAN, C2H2, and HCOOH) in the Asian monsoon UTLS from the airborne limb imager GLORIA during StratoClim 2017. Enhancements are observed up to 16 km altitude, and PAN and C2H2 even up to 18 km. Two atmospheric models, CAMS and EMAC, reproduce the pollutant's large-scale structures but not finer structures. Convection is investigated using backward trajectories of the models ATLAS and TRACZILLA with advanced detection of convection.
Silvia Bucci, Bernard Legras, Pasquale Sellitto, Francesco D'Amato, Silvia Viciani, Alessio Montori, Antonio Chiarugi, Fabrizio Ravegnani, Alexey Ulanovsky, Francesco Cairo, and Fred Stroh
Atmos. Chem. Phys., 20, 12193–12210, https://doi.org/10.5194/acp-20-12193-2020, https://doi.org/10.5194/acp-20-12193-2020, 2020
Short summary
Short summary
The paper presents and evaluates a transport analysis method to study the convective injection of air in the upper troposphere–lower stratosphere of the Asian monsoon anticyclone region. The approach is thereby used to analyse the trace gas data collected during the StratoClim aircraft campaign. The results showed that fresh convective air can be injected fast at a high level of the atmosphere (above 17 km), with potential impacts on the stratospheric chemistry of the Northern Hemisphere.
Bernard Legras and Silvia Bucci
Atmos. Chem. Phys., 20, 11045–11064, https://doi.org/10.5194/acp-20-11045-2020, https://doi.org/10.5194/acp-20-11045-2020, 2020
Short summary
Short summary
The Asian monsoon is the most active region bringing surface compounds by convection to the stratosphere during summer. We study the transport pathways and the trapping within the upper-layer anticyclonic circulation. Above 15 km, the confinement can be represented by a uniform ascent over continental Asia of about 200 m per day and a uniform loss to other regions with a characteristic time of 2 weeks. We rule out the presence of a
chimneyproposed in previous studies over the Tibetan Plateau.
Aurélien Podglajen, Albert Hertzog, Riwal Plougonven, and Bernard Legras
Atmos. Chem. Phys., 20, 9331–9350, https://doi.org/10.5194/acp-20-9331-2020, https://doi.org/10.5194/acp-20-9331-2020, 2020
Short summary
Short summary
Thanks to the increase in resolution, numerical weather prediction models resolve a growing fraction of the gravity wave (GW) spectrum. Here, we assess the representation of Lagrangian GW fluctuations by comparing trajectories in the models to long-duration balloon observations. Most characteristics of the observed GW spectrum, such as near-inertial oscillations, are qualitatively present. However, the variability remains underestimated, emphasizing the continuous need for GW parameterizations.
Jonathon S. Wright, Xiaoyi Sun, Paul Konopka, Kirstin Krüger, Bernard Legras, Andrea M. Molod, Susann Tegtmeier, Guang J. Zhang, and Xi Zhao
Atmos. Chem. Phys., 20, 8989–9030, https://doi.org/10.5194/acp-20-8989-2020, https://doi.org/10.5194/acp-20-8989-2020, 2020
Short summary
Short summary
High clouds are influential in tropical climate. Although reanalysis cloud fields are essentially model products, they are indirectly constrained by observations and offer global coverage with direct links to advanced water and energy cycle metrics, giving them many useful applications. We describe how high cloud fields are generated in reanalyses, assess their realism and reliability in the tropics, and evaluate how differences in these fields affect other aspects of the reanalysis state.
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.
Corinna Kloss, Gwenaël Berthet, Pasquale Sellitto, Felix Ploeger, Silvia Bucci, Sergey Khaykin, Fabrice Jégou, Ghassan Taha, Larry W. Thomason, Brice Barret, Eric Le Flochmoen, Marc von Hobe, Adriana Bossolasco, Nelson Bègue, and Bernard Legras
Atmos. Chem. Phys., 19, 13547–13567, https://doi.org/10.5194/acp-19-13547-2019, https://doi.org/10.5194/acp-19-13547-2019, 2019
Short summary
Short summary
With satellite measurements and transport models, we show that a plume resulting from strong Canadian fires in July/August 2017 was not only distributed throughout the northern/higher latitudes, but also reached the faraway tropics, aided by the circulation of Asian monsoon anticyclone. The regional climate impact in the wider Asian monsoon area in September exceeds the impact of the Asian tropopause aerosol layer by a factor of ~ 3 and compares to that of an advected moderate volcanic eruption.
Henda Guermazi, Pasquale Sellitto, Juan Cuesta, Maxim Eremenko, Mathieu Lachatre, Sylvain Mailler, Elisa Carboni, Giuseppe Salerno, Tommaso Caltabiano, Laurent Menut, Mohamed Moncef Serbaji, Farhat Rekhiss, and Bernard Legras
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2019-341, https://doi.org/10.5194/amt-2019-341, 2019
Revised manuscript not accepted
Felix Ploeger, Bernard Legras, Edward Charlesworth, Xiaolu Yan, Mohamadou Diallo, Paul Konopka, Thomas Birner, Mengchu Tao, Andreas Engel, and Martin Riese
Atmos. Chem. Phys., 19, 6085–6105, https://doi.org/10.5194/acp-19-6085-2019, https://doi.org/10.5194/acp-19-6085-2019, 2019
Short summary
Short summary
We analyse the change in the circulation of the middle atmosphere based on current generation meteorological reanalysis data sets. We find that long-term changes from 1989 to 2015 are similar for the chosen reanalyses, mainly resembling the forced response in climate model simulations to climate change. For shorter periods circulation changes are less robust, and the representation of decadal variability appears to be a major uncertainty for modelling the circulation of the middle atmosphere.
Mohamadou Diallo, Paul Konopka, Michelle L. Santee, Rolf Müller, Mengchu Tao, Kaley A. Walker, Bernard Legras, Martin Riese, Manfred Ern, and Felix Ploeger
Atmos. Chem. Phys., 19, 425–446, https://doi.org/10.5194/acp-19-425-2019, https://doi.org/10.5194/acp-19-425-2019, 2019
Short summary
Short summary
This paper assesses the structural changes in the shallow and transition branches of the BDC induced by El Nino using the Lagrangian model simulations driven by ERAi and JRA-55 combined with MLS observations. We found a clear evidence of a weakening of the transition branch due to an upward shift in the dissipation height of the planetary and gravity waves and a strengthening of the shallow branch due to enhanced GW breaking in the tropics–subtropics and PW breaking at high latitudes.
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.
Mohamadou Diallo, Bernard Legras, Eric Ray, Andreas Engel, and Juan A. Añel
Atmos. Chem. Phys., 17, 3861–3878, https://doi.org/10.5194/acp-17-3861-2017, https://doi.org/10.5194/acp-17-3861-2017, 2017
Short summary
Short summary
We construct a new monthly zonal mean CO2 distribution from the upper troposphere to the stratosphere over the 2000–2010 period. The main features of the CO2 distribution are consistent with expected variability due to the transport of long-lived trace gases by the Brewer–Dobson circulation. The method used to construct this CO2 product is unique and should be useful for model and satellite validation in the upper troposphere and stratosphere.
Pasquale Sellitto, Alcide di Sarra, Stefano Corradini, Marie Boichu, Hervé Herbin, Philippe Dubuisson, Geneviève Sèze, Daniela Meloni, Francesco Monteleone, Luca Merucci, Justin Rusalem, Giuseppe Salerno, Pierre Briole, and Bernard Legras
Atmos. Chem. Phys., 16, 6841–6861, https://doi.org/10.5194/acp-16-6841-2016, https://doi.org/10.5194/acp-16-6841-2016, 2016
Short summary
Short summary
We combine plume dispersion and radiative transfer modelling, and satellite and surface remote sensing observations to study the regional influence of a relatively weak volcanic eruption from Mount Etna (25–27 October 2013) on the optical/micro-physical properties of Mediterranean aerosols. Our results indicate that even relatively weak volcanic eruptions may produce an observable effect on the aerosol properties at the regional scale, with a significant impact on the regional radiative balance.
Aurélien Podglajen, Riwal Plougonven, Albert Hertzog, and Bernard Legras
Atmos. Chem. Phys., 16, 3881–3902, https://doi.org/10.5194/acp-16-3881-2016, https://doi.org/10.5194/acp-16-3881-2016, 2016
Short summary
Short summary
The Weather Research and Forecast model is used to simulate a large-scale tropical tropopause layer (TTL) cirrus. Validated with satellite observations, the simulation shows that several clouds successively form due to a large-scale uplift initiated by the intrusion of air from the midlatitudes. The simulated cloud field is found as sensitive to the initial condition as it is to the choice of the microphysics parametrisation. The cloud impacts on the radiative and water budgets are estimated.
P. Sellitto and B. Legras
Atmos. Meas. Tech., 9, 115–132, https://doi.org/10.5194/amt-9-115-2016, https://doi.org/10.5194/amt-9-115-2016, 2016
Short summary
Short summary
This study investigates the sensitivity of TIR satellite nadir observations to the chemical composition and the size distribution of idealized UTLS sulfate aerosol layers. The dependence of the sulfate spectral signature, between 700 and 1200 cm−1, on the sulfuric acid mixing ratio, effective number concentration and radius, as well as the role of interfering parameters, is analysed. The information content of broadband and high-spectral-resolution observations is finally discussed.
T. Dinh, A. Podglajen, A. Hertzog, B. Legras, and R. Plougonven
Atmos. Chem. Phys., 16, 35–46, https://doi.org/10.5194/acp-16-35-2016, https://doi.org/10.5194/acp-16-35-2016, 2016
M. Bolot, B. Legras, and E. J. Moyer
Atmos. Chem. Phys., 13, 7903–7935, https://doi.org/10.5194/acp-13-7903-2013, https://doi.org/10.5194/acp-13-7903-2013, 2013
M. Diallo, B. Legras, and A. Chédin
Atmos. Chem. Phys., 12, 12133–12154, https://doi.org/10.5194/acp-12-12133-2012, https://doi.org/10.5194/acp-12-12133-2012, 2012
M. Reverdy, V. Noel, H. Chepfer, and B. Legras
Atmos. Chem. Phys., 12, 12081–12101, https://doi.org/10.5194/acp-12-12081-2012, https://doi.org/10.5194/acp-12-12081-2012, 2012
Related subject area
Subject: Dynamics | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
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
Divergent convective outflow in large eddy simulations
Climatology and variability of air mass transport from the boundary layer to the Asian monsoon anticyclone
Uncertainty in Parameterized Convection Remains a Key Obstacle for Estimating Surface Fluxes of Carbon Dioxide
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
Robust winter warming over Eurasia under stratospheric sulfate geoengineering – the role of stratospheric dynamics
Parameterizing the vertical downward dispersion of ship exhaust gas in the near field
Anthropogenic aerosol forcing of the Atlantic meridional overturning circulation and the associated mechanisms in CMIP6 models
Sensitivities of the Madden–Julian oscillation forecasts to configurations of physics in the ECMWF global model
Sensitivity of modeled Indian monsoon to Chinese and Indian aerosol emissions
The spring transition of the North Pacific jet and its relation to deep stratosphere-to-troposphere mass transport over western North America
Very long-period oscillations in the atmosphere (0–110 km)
Identification of molecular cluster evaporation rates, cluster formation enthalpies and entropies by Monte Carlo method
The “urban meteorology island”: a multi-model ensemble analysis
Validation of reanalysis Southern Ocean atmosphere trends using sea ice data
Revisiting the trend in the occurrences of the “warm Arctic–cold Eurasian continent” temperature pattern
A microphysics guide to cirrus – Part 2: Climatologies of clouds and humidity from observations
Ceilometers as planetary boundary layer height detectors and a corrective tool for COSMO and IFS models
Using a coupled large-eddy simulation–aerosol radiation model to investigate urban haze: sensitivity to aerosol loading and meteorological conditions
Confinement of air in the Asian monsoon anticyclone and pathways of convective air to the stratosphere during the summer season
On the climate sensitivity and historical warming evolution in recent coupled model ensembles
Surface processes in the 7 November 2014 medicane from air–sea coupled high-resolution numerical modelling
Hadley cell expansion in CMIP6 models
Atmospheric teleconnection processes linking winter air stagnation and haze extremes in China with regional Arctic sea ice decline
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.
Edward Groot and Holger Tost
EGUsphere, https://doi.org/10.5194/egusphere-2022-1261, https://doi.org/10.5194/egusphere-2022-1261, 2022
Short summary
Short summary
It is shown that the outflow from cumulonimbus clouds or thunderstorms in the upper troposphere/lower stratosphere in idealised high resolution simulations (LES) depends linearly on the net amount of latent heat released by the cloud for fixed geometrical structure of the cloud. However, it is shown that in more realistic situations, convective organisation and aggregation (collecting mechanisms of cumulonimbus clouds) affect the amount of outflow non-linearly through non-idealised geometry.
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.
Andrew E. Schuh and Andrew R. Jacobson
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-616, https://doi.org/10.5194/acp-2022-616, 2022
Revised manuscript accepted for ACP
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 CO2 to estimate surface fluxes of CO2.
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.
Antara Banerjee, Amy H. Butler, Lorenzo M. Polvani, Alan Robock, Isla R. Simpson, and Lantao Sun
Atmos. Chem. Phys., 21, 6985–6997, https://doi.org/10.5194/acp-21-6985-2021, https://doi.org/10.5194/acp-21-6985-2021, 2021
Short summary
Short summary
We find that simulated stratospheric sulfate geoengineering could lead to warmer Eurasian winters alongside a drier Mediterranean and wetting to the north. These effects occur due to the strengthening of the Northern Hemisphere stratospheric polar vortex, which shifts the North Atlantic Oscillation to a more positive phase. We find the effects in our simulations to be much more significant than the wintertime effects of large tropical volcanic eruptions which inject much less sulfate aerosol.
Ronny Badeke, Volker Matthias, and David Grawe
Atmos. Chem. Phys., 21, 5935–5951, https://doi.org/10.5194/acp-21-5935-2021, https://doi.org/10.5194/acp-21-5935-2021, 2021
Short summary
Short summary
This work aims to describe the physical distribution of ship exhaust gases in the near field, e.g., inside of a harbor. Results were calculated with a mathematical model for different meteorological and technical conditions. It has been shown that large vessels like cruise ships have a significant effect of up to 55 % downward movement of exhaust gas, as they can disturb the ground near wind circulation. This needs to be considered in urban air pollution studies.
Taufiq Hassan, Robert J. Allen, Wei Liu, and Cynthia A. Randles
Atmos. Chem. Phys., 21, 5821–5846, https://doi.org/10.5194/acp-21-5821-2021, https://doi.org/10.5194/acp-21-5821-2021, 2021
Short summary
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.
Jun-Ichi Yano and Nils P. Wedi
Atmos. Chem. Phys., 21, 4759–4778, https://doi.org/10.5194/acp-21-4759-2021, https://doi.org/10.5194/acp-21-4759-2021, 2021
Short summary
Short summary
Sensitivities of forecasts of the Madden–Julian oscillation (MJO) to various different configurations of the physics are examined with the global model of ECMWF's Integrated Forecasting System (IFS). The motivation for the study was to simulate the MJO as a nonlinear free wave. To emulate free dynamics in the IFS,
various momentum dissipation terms (
friction) as well as diabatic heating were selectively turned off over the tropics for the range of the latitudes from 20° S to 20° N.
Peter Sherman, Meng Gao, Shaojie Song, Alex T. Archibald, Nathan Luke Abraham, Jean-François Lamarque, Drew Shindell, Gregory Faluvegi, and Michael B. McElroy
Atmos. Chem. Phys., 21, 3593–3605, https://doi.org/10.5194/acp-21-3593-2021, https://doi.org/10.5194/acp-21-3593-2021, 2021
Short summary
Short summary
The aims here are to assess the role of aerosols in India's monsoon precipitation and to determine the relative contributions from Chinese and Indian emissions using CMIP6 models. We find that increased sulfur emissions reduce precipitation, which is primarily dynamically driven due to spatial shifts in convection over the region. A significant increase in precipitation (up to ~ 20 %) is found only when both Indian and Chinese sulfate emissions are regulated.
Melissa L. Breeden, Amy H. Butler, John R. Albers, Michael Sprenger, and Andrew O'Neil Langford
Atmos. Chem. Phys., 21, 2781–2794, https://doi.org/10.5194/acp-21-2781-2021, https://doi.org/10.5194/acp-21-2781-2021, 2021
Short summary
Short summary
Prior research has found a maximum in deep stratosphere-to-troposphere mass/ozone transport over the western United States in boreal spring, which can enhance surface ozone concentrations, reducing air quality. We find that the winter-to-summer evolution of the north Pacific jet increases the frequency of stratospheric intrusions that drive transport, helping explain the observed maximum. The El Niño–Southern Oscillation affects the timing of the spring jet transition and therefore transport.
Dirk Offermann, Christoph Kalicinsky, Ralf Koppmann, and Johannes Wintel
Atmos. Chem. Phys., 21, 1593–1611, https://doi.org/10.5194/acp-21-1593-2021, https://doi.org/10.5194/acp-21-1593-2021, 2021
Short summary
Short summary
Atmospheric oscillations with periods of up to several 100 years exist at altitudes up to 110 km. They are also seen in computer models (GCMs) of the atmospheric. They are often attributed to external influences from the sun, from the oceans, or from atmospheric constituents. This is difficult to verify as the atmosphere cannot be manipulated in an experiment. However, a GCM can be changed arbitrarily. Doing so, we find that long-period oscillations may be excited internally in the atmosphere.
Anna Shcherbacheva, Tracey Balehowsky, Jakub Kubečka, Tinja Olenius, Tapio Helin, Heikki Haario, Marko Laine, Theo Kurtén, and Hanna Vehkamäki
Atmos. Chem. Phys., 20, 15867–15906, https://doi.org/10.5194/acp-20-15867-2020, https://doi.org/10.5194/acp-20-15867-2020, 2020
Short summary
Short summary
Atmospheric new particle formation and cluster growth to aerosol particles is an important field of research, in particular due to the climate change phenomenon. Evaporation rates are very difficult to account for but they are important to explain the formation and growth of particles. Different quantum chemistry (QC) methods produce substantially different values for the evaporation rates. We propose a novel approach for inferring evaporation rates of clusters from available measurements.
Jan Karlický, Peter Huszár, Tereza Nováková, Michal Belda, Filip Švábik, Jana Ďoubalová, and Tomáš Halenka
Atmos. Chem. Phys., 20, 15061–15077, https://doi.org/10.5194/acp-20-15061-2020, https://doi.org/10.5194/acp-20-15061-2020, 2020
Short summary
Short summary
Cities are characterized by their impact on various meteorological variables. Our study aims to generalize these modifications into a single phenomenon – the urban meteorology island (UMI). A wide ensemble of Weather Research and Forecasting (WRF) and Regional Climate Model (RegCM) simulations investigated urban-induced modifications as individual UMI components. Significant changes are found in most of the discussed meteorological variables with a strong impact of specific model simulations.
William R. Hobbs, Andrew R. Klekociuk, and Yuhang Pan
Atmos. Chem. Phys., 20, 14757–14768, https://doi.org/10.5194/acp-20-14757-2020, https://doi.org/10.5194/acp-20-14757-2020, 2020
Short summary
Short summary
Reanalysis products are an invaluable tool for representing variability and long-term trends in regions with limited in situ data. However, validation of these products is difficult because of that lack of station data. Here we present a novel assessment of eight reanalyses over the polar Southern Ocean, leveraging the close relationship between trends in sea ice cover and surface air temperature, that provides clear guidance on the most reliable product for Antarctic research.
Lejiang Yu, Shiyuan Zhong, Cuijuan Sui, and Bo Sun
Atmos. Chem. Phys., 20, 13753–13770, https://doi.org/10.5194/acp-20-13753-2020, https://doi.org/10.5194/acp-20-13753-2020, 2020
Short summary
Short summary
The recent increasing trend of "warm Arctic, cold continents" has attracted much attention, but it remains debatable as to what forces are behind this phenomenon. Sea surface temperature (SST) over the central North Pacific and the North Atlantic oceans influences the trend. On an interdecadal timescale, the recent increase in the occurrences of the warm Arctic–cold Eurasia pattern is a fragment of the interdecadal variability of SST over the Atlantic Ocean and over the central Pacific Ocean.
Martina Krämer, Christian Rolf, Nicole Spelten, Armin Afchine, David Fahey, Eric Jensen, Sergey Khaykin, Thomas Kuhn, Paul Lawson, Alexey Lykov, Laura L. Pan, Martin Riese, Andrew Rollins, Fred Stroh, Troy Thornberry, Veronika Wolf, Sarah Woods, Peter Spichtinger, Johannes Quaas, and Odran Sourdeval
Atmos. Chem. Phys., 20, 12569–12608, https://doi.org/10.5194/acp-20-12569-2020, https://doi.org/10.5194/acp-20-12569-2020, 2020
Short summary
Short summary
To improve the representations of cirrus clouds in climate predictions, extended knowledge of their properties and geographical distribution is required. This study presents extensive airborne in situ and satellite remote sensing climatologies of cirrus and humidity, which serve as a guide to cirrus clouds. Further, exemplary radiative characteristics of cirrus types and also in situ observations of tropical tropopause layer cirrus and humidity in the Asian monsoon anticyclone are shown.
Leenes Uzan, Smadar Egert, Pavel Khain, Yoav Levi, Elyakom Vadislavsky, and Pinhas Alpert
Atmos. Chem. Phys., 20, 12177–12192, https://doi.org/10.5194/acp-20-12177-2020, https://doi.org/10.5194/acp-20-12177-2020, 2020
Short summary
Short summary
Detection of the planetary boundary layer (PBL) height is crucial to various fields, from air pollution assessment to weather prediction. We examined the diurnal summer PBL height by eight ceilometers in Israel, radiosonde profiles, the global IFS, and regional COSMO models. Our analysis utilized the bulk Richardson number method, the parcel method, and the wavelet covariance transform method. A novel correction tool to improve model results against in-situ ceilometer measurements is introduced.
Jessica Slater, Juha Tonttila, Gordon McFiggans, Paul Connolly, Sami Romakkaniemi, Thomas Kühn, and Hugh Coe
Atmos. Chem. Phys., 20, 11893–11906, https://doi.org/10.5194/acp-20-11893-2020, https://doi.org/10.5194/acp-20-11893-2020, 2020
Short summary
Short summary
The feedback effect between aerosol particles, radiation and meteorology reduces turbulent motion and results in increased surface aerosol concentrations during Beijing haze. Observational analysis and regional modelling studies have examined the feedback effect but these studies are limited. In this work, we set up a high-resolution model for the Beijing environment to examine the sensitivity of the aerosol feedback effect to initial meteorological conditions and aerosol loading.
Bernard Legras and Silvia Bucci
Atmos. Chem. Phys., 20, 11045–11064, https://doi.org/10.5194/acp-20-11045-2020, https://doi.org/10.5194/acp-20-11045-2020, 2020
Short summary
Short summary
The Asian monsoon is the most active region bringing surface compounds by convection to the stratosphere during summer. We study the transport pathways and the trapping within the upper-layer anticyclonic circulation. Above 15 km, the confinement can be represented by a uniform ascent over continental Asia of about 200 m per day and a uniform loss to other regions with a characteristic time of 2 weeks. We rule out the presence of a
chimneyproposed in previous studies over the Tibetan Plateau.
Clare Marie Flynn and Thorsten Mauritsen
Atmos. Chem. Phys., 20, 7829–7842, https://doi.org/10.5194/acp-20-7829-2020, https://doi.org/10.5194/acp-20-7829-2020, 2020
Short summary
Short summary
The range of climate sensitivity of models participating in CMIP6 has increased relative to models participating in CMIP5 due to decreases in the total feedback parameter. This is caused by increases in the shortwave all-sky and clear-sky feedbacks, particularly over the Southern Ocean. These shifts between CMIP6 and CMIP5 did not arise by chance. Both CMIP5 and CMIP6 models are found to exhibit aerosol forcing that is too strong, causing too much cooling relative to observations.
Marie-Noëlle Bouin and Cindy Lebeaupin Brossier
Atmos. Chem. Phys., 20, 6861–6881, https://doi.org/10.5194/acp-20-6861-2020, https://doi.org/10.5194/acp-20-6861-2020, 2020
Short summary
Short summary
A coupled, kilometre-scale simulation of a medicane is used to assess the impact of the ocean feedback and role of surface fluxes. Sea surface temperature (SST) drop is much weaker than for tropical cyclones, resulting in no impact on the cyclone. Surface fluxes depend mainly on wind and SST for evaporation and on air temperature for sensible heat. Processes in the Mediterranean, like advection of continental air, rain evaporation and dry air intrusion, play a role in cyclone development.
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.
Yufei Zou, Yuhang Wang, Zuowei Xie, Hailong Wang, and Philip J. Rasch
Atmos. Chem. Phys., 20, 4999–5017, https://doi.org/10.5194/acp-20-4999-2020, https://doi.org/10.5194/acp-20-4999-2020, 2020
Short summary
Short summary
We analyze the relationship between winter air stagnation and pollution extremes over eastern China and preceding Arctic sea ice loss based on climate modeling and dynamic diagnoses. We find significant increases in both the probability and intensity of air stagnation extremes in the modeling result driven by regional sea ice and sea surface temperature changes over the Pacific sector of the Arctic. We reveal the considerable impact of the Arctic climate change on mid-latitude weather extremes.
Cited articles
Abalos, M., Randel, W. J., and Serrano, E.: Variability in upwelling across
the tropical tropopause and correlations with tracers in the lower
stratosphere, Atmos. Chem. Phys., 12, 11505–11517,
https://doi.org/10.5194/acp-12-11505-2012, 2012.
Adler, R. F. and Mack, R. A.: Thunderstorm Cloud Top Dynamics as Inferred
from Satellite Observations and a Cloud Top Parcel Model, J.
Atmos. Sci., 43, 1945–1960,
https://doi.org/10.1175/1520-0469(1986)043<1945:TCTDAI>2.0.CO;2, 1986.
Andrews, D. G., Holton, J. R., and Leovy, C. B.: Middle atmosphere dynamics,
no. v. 40 in International geophysics series, Academic Press, Orlando, 1987.
Appenzeller, C., Holton, J. R., and Rosenlof, K. H.: Seasonal variation of
mass transport across the tropopause, J. Geophys. Res., 101,
15071–15071, https://doi.org/10.1029/96JD00821, 1996.
Aschmann, J., Sinnhuber, B.-M., Atlas, E. L., and Schauffler, S. M.: Modeling
the transport of very short-lived substances into the tropical upper
troposphere and lower stratosphere, Atmos. Chem. Phys., 9, 9237–9247,
https://doi.org/10.5194/acp-9-9237-2009, 2009.
Bannister, R., O'Neill, A., Gregory, A., and Nissen,
K.: The role of the south-east Asian monsoon and other seasonal features in
creating the “tape-recorder” signal in the Unified Model, Q. J. Roy.
Meteorol. Soc., 130, 1531–1554, https://doi.org/10.1256/qj.03.106, 2004.
Bergman, J. W., Jensen, E. J., Pfister, L., and Yang, Q.: Seasonal
differences of vertical-transport efficiency in the tropical tropopause
layer: On the interplay between tropical deep convection, large-scale
vertical ascent, and horizontal circulations, J. Geophys. Res., 117, D05302,
https://doi.org/10.1029/2011JD016992, 2012.
Bergman, J. W., Fierli, F., Jensen, E. J., Honomichl, S., and Pan, L. L.:
Boundary layer sources for the Asian anticyclone: Regional contributions to a
vertical conduit, J. Geophys. Res.-Atmos., 118, 2560–2575,
https://doi.org/10.1002/jgrd.50142, 2013.
Bergman, J. W., Pfister, L., and Yang, Q.: Identifying robust transport
features of the upper tropical troposphere, J. Geophys. Res., 120,
6758–6776, https://doi.org/10.1002/2015JD023523, 2015.
Chen, B., Xu, X. D., Yang, S., and Zhao, T. L.: Climatological perspectives
of air transport from atmospheric boundary layer to tropopause layer over
Asian monsoon regions during boreal summer inferred from Lagrangian approach,
Atmos. Chem. Phys., 12, 5827–5839, https://doi.org/10.5194/acp-12-5827-2012, 2012.
Corti, T., Luo, B. P., Fu, Q., Vömel, H., and Peter, T.: The impact of
cirrus clouds on tropical troposphere-to-stratosphere transport, Atmos. Chem.
Phys., 6, 2539–2547, https://doi.org/10.5194/acp-6-2539-2006, 2006.
Corti, T., Luo, B. P., de Reus, M., Brunner, D., Cairo, F., Mahoney, M. J.,
Martucci, G., Matthey, R., Mitev, V., dos Santos, F. H., Schiller, C., Shur,
G., Sitnikov, N. M., Spelten, N., Vössing, H. J., Borrmann, S., and
Peter, T.: Unprecedented evidence for deep convection hydrating the tropical
stratosphere, Geophys. Res. Lett., 35, L10810,
https://doi.org/10.1029/2008GL033641, 2008.
Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P.,
Kobayashi,
S., Andrae, U., Balmaseda, M. A., Balsamo, G., Bauer, P., Bechtold, P.,
Beljaars, A. C. M., Van de Berg, L. V. D., Bidlot, J., Bormann, N., Delsol,
C., Dragani, R., Fuentes, M., Geer, A. J., Haimberger, L., Healy, S. B.,
Hersbach, H., Hólm, E. V., Isaksen, L., Kållberg, P., Köhler, M.,
Matricardi, M., McNally, A. P., Monge-Sanz, B. M., Morcrette, J. J., Park,
B.-K., Peubey, C., de Rosnay, P., Tavolato, C., Thépaut, J.-N., and
Vitart, F.: The ERA-Interim reanalysis: configuration and performance of
the data assimilation system, Q. J. Roy. Meteorol.
Soc., 137, 553–597, https://doi.org/10.1002/qj.828, 2011.
Devasthale, A. and Fueglistaler, S.: A climatological perspective of deep
convection penetrating the TTL during the Indian summer monsoon from the
AVHRR and MODIS instruments, Atmos. Chem. Phys., 10, 4573–4582,
https://doi.org/10.5194/acp-10-4573-2010, 2010.
Folkins, I., Loewenstein, M., Podolske, J., Oltmans, S. J., and Proffitt, M.:
A
barrier to vertical mixing at 14 km in the tropics: Evidence from ozonesondes
and aircraft measurements, J. Geophys. Res., 104,
22095–22095, https://doi.org/10.1029/1999JD900404, 1999.
Fu, Q., Hu, Y., and Yang, Q.: Identifying the top of the tropical tropopause
layer from vertical mass flux analysis and CALIPSO lidar cloud
observations, Geophys. Res. Lett., 34, L14813,
https://doi.org/10.1029/2007GL030099, 2007.
Fu, R., Hu, Y., Wright, J. S., Jiang, J. H., Dickinson, R. E., Chen, M.,
Filipiak, M., Read, W. G., Waters, J. W., and Wu, D. L.: Short circuit of
water vapor and polluted air to the global stratosphere by convective
transport over the Tibetan Plateau, P. Natl. Acad.
Sci. USA, 103, 5664–5669, https://doi.org/10.1073/pnas.0601584103, 2006.
Fueglistaler, S., Wernli, H., and Peter, T.: Tropical
troposphere-to-stratosphere transport inferred from trajectory calculations,
J. Geophys. Res., 109, D03108, https://doi.org/10.1029/2003JD004069, 2004.
Fueglistaler, S., Dessler, A. E., Dunkerton, T. J., Folkins, I., Fu, Q., and
Mote, P. W.: Tropical tropopause layer, Rev. Geophys., 47,
RG1004, https://doi.org/10.1029/2008RG000267, 2009.
Gettelman, A., Salby, M. L., and Sassi, F.: Distribution and influence of
convection in the tropical tropopause region, J. Geophys.
Res., 107, 4080–4080, https://doi.org/10.1029/2001JD001048, 2002.
Gettelman, A., Lauritzen, P. H., Park, M., and Kay, J. E.: Processes
regulating
short-lived species in the tropical tropopause layer, J. Geophys.
Res., 114, D13303, https://doi.org/10.1029/2009JD011785, 2009.
Hall, T. M. and Holzer, M.: Advective-diffusive mass flux and implications
for stratosphere-troposphere exchange, Geophys. Res. Lett., 30, 1222,
https://doi.org/10.1029/2002GL016419, 2003.
Hamann, U., Walther, A., Baum, B., Bennartz, R., Bugliaro, L., Derrien, M.,
Francis, P. N., Heidinger, A., Joro, S., Kniffka, A., Le Gléau, H.,
Lockhoff, M., Lutz, H.-J., Meirink, J. F., Minnis, P., Palikonda, R.,
Roebeling, R., Thoss, A., Platnick, S., Watts, P., and Wind, G.: Remote
sensing of cloud top pressure/height from SEVIRI: analysis of ten current
retrieval algorithms, Atmos. Meas. Tech., 7, 2839–2867,
https://doi.org/10.5194/amt-7-2839-2014, 2014.
Heath, N. K. and Fuelberg, H. E.: Using a WRF simulation to examine regions
where convection impacts the Asian summer monsoon anticyclone, Atmos. Chem.
Phys., 14, 2055–2070, https://doi.org/10.5194/acp-14-2055-2014, 2014.
Highwood, E. J. and Hoskins, B. J.: The tropical tropopause, Q. J.
Roy. Meteorol. Soc., 124, 1579–1604, https://doi.org/10.1002/qj.49712454911, 1998.
Hodges, K. I., Chappell, D. W., Robinson, G. J., and Yang, G.: An improved
algorithm for generating global window brightness temperatures from multiple
satellite infrared imagery, J. Atmos. Ocean. Tech., 17, 1296–1312, 2000.
Holton, J. R., Haynes, P. H., McIntyre, M. E., Douglass, A. R., Rood,
R. B., and Pfister, L.: Stratosphere-troposphere exchange, Rev. Geophys.,
33, 403–439, https://doi.org/10.1029/95RG02097, 1995.
Holzer, M. and Hall, T. M.: Transit-Time and Tracer-Age Distributions in
Geophysical Flows, J. Atmos. Sci., 57, 3539–3558,
https://doi.org/10.1175/1520-0469(2000)057<3539:TTATAD>2.0.CO;2, 2000.
James, R., Bonazzola, M., Legras, B., Surbled, K., and Fueglistaler, S.:
Water
vapor transport and dehydration above convective outflow during Asian
monsoon, Geophys. Res. Lett., 35, L20810,
https://doi.org/10.1029/2008GL035441, 2008.
Johansson, E., Devasthale, A., L'Ecuyer, T., Ekman, A. M. L., and Tjernström,
M.: The vertical structure of cloud radiative heating over the Indian
subcontinent during summer monsoon, Atmos. Chem. Phys., 15,
11557–11570, https://doi.org/10.5194/acp-15-11557-2015, 2015.
Kobayashi, S., Ota, Y., Harada, Y., Ebita, A., Moriya, M., Onoda, H., Onogi,
K., Kamahori, H., Kobayashi, C., Endo, H., Miyaoka, K., and Takahashi, K.:
The JRA-55 Reanalysis: General Specifications and Basic Characteristics,
J. Meteorol. Soc. Jpn. Ser. II, 93, 5–48,
https://doi.org/10.2151/jmsj.2015-001, 2015.
Kwon, E.-H., Sohn, B.-J., Schmetz, J., and Watts, P.: Intercomparison of
height
assignment methods for opaque clouds over the tropics, Asia-Pac. J. Atmos.
Sci., 46, 11–19, https://doi.org/10.1007/s13143-010-0002-7, 2010.
Legras, B., Pisso, I., Berthet, G., and Lefèvre, F.: Variability of the
Lagrangian turbulent diffusion in the lower stratosphere, Atmos. Chem. Phys.,
5, 1605–1622, https://doi.org/10.5194/acp-5-1605-2005, 2005.
Li, Jian-Dong and Mao, Jiang-Yu: A preliminary evaluation of
global and East Asian cloud radiative effects in reanalyses,
Atmos. Ocean. Sci. Lett., 8, 100–106, https://doi.org/10.3878/AOSL20140093, 2015.
Liu, C. and Zipser, E. J.: Global distribution of convection penetrating the
tropical tropopause, J. Geophys. Res., 110,
D23104, https://doi.org/10.1029/2005JD006063, 2005.
Liu, X. M., Rivière, E. D., Marécal, V., Durry, G., Hamdouni, A.,
Arteta, J., and Khaykin, S.: Stratospheric water vapour budget and convection
overshooting the tropopause: modelling study from SCOUT-AMMA, Atmos. Chem.
Phys., 10, 8267–8286, https://doi.org/10.5194/acp-10-8267-2010, 2010.
Luo, Z., Liu, G. Y., and Stephens, G. L.: CloudSat adding new insight into
tropical penetrating convection, Geophys. Res. Lett., 35,
L19819, https://doi.org/10.1029/2008GL035330, 2008.
Minnis, P., Yost, C. R., Sun-Mack, S., and Chen, Y.: Estimating the top
altitude of optically thick ice clouds from thermal infrared satellite
observations using CALIPSO data, Geophys. Res. Lett., 35,
L12801, https://doi.org/10.1029/2008GL033947, 2008.
Molod, A., Takacs, L., Suarez, M., and Bacmeister, J.: Development of the
GEOS-5 atmospheric general circulation model: evolution from MERRA to
MERRA2, Geosci. Model Dev., 8, 1339–1356,
https://doi.org/10.5194/gmd-8-1339-2015, 2015.
Orbe, C., Waugh, D. W., and Newman, P. A.: Air-mass origin in the tropical
lower stratosphere: The influence of Asian boundary layer air, Geophys.
Res. Lett., 42, 4240–4248, https://doi.org/10.1002/2015GL063937, 2015.
Park, M., Randel, W. J., Gettelman, A., Massie, S. T., and Jiang, J. H.:
Transport above the Asian summer monsoon anticyclone inferred from Aura
Microwave Limb Sounder tracers, J. Geophys. Res., 112,
D16309, https://doi.org/10.1029/2006JD008294, 2007.
Park, M., Randel, W. J., Emmons, L. K., and Livesey, N. J.: Transport
pathways
of carbon monoxide in the Asian summer monsoon diagnosed from Model of Ozone
and Related Tracers (MOZART), J. Geophys. Res., 114,
D08303, https://doi.org/10.1029/2008JD010621, 2009.
Pisso, I. and Legras, B.: Turbulent vertical diffusivity in the sub-tropical
stratosphere, Atmos. Chem. Phys., 8, 697–707, https://doi.org/10.5194/acp-8-697-2008,
2008.
Ploeger, F., Konopka, P., Müller, R., Fueglistaler, S., Schmidt, T.,
Manners, J. C., Grooß, J.-U., Günther, G., Forster, P. M., and Riese,
M.: Horizontal transport affecting trace gas seasonality in the Tropical
Tropopause Layer (TTL), J. Geophys. Res., 117, D09303,
https://doi.org/10.1029/2011JD017267, 2012.
Podglajen, A., Hertzog, A., Plougonven, R., and Žagar, N.: Assessment of
the accuracy of (re)analyses in the equatorial lower stratosphere, J.
Geophys. Res.-Atmos., 119, 11166–11188,
https://doi.org/10.1002/2014JD021849, 2014.
Rienecker, M. M., Suarez, M. J., Gelaro, R., Todling, R., Bacmeister, J., Liu,
E., Bosilovich, M. G., Schubert, S. D., Takacs, L., Kim, G.-K., Bloom, S.,
Chen, J., Collins, D., Conaty, A., da Silva, A., Gu, W., Joiner, J., Koster,
R. D., Lucchesi, R., Molod, A., Owens, T., Pawson, S., Pegion, P., Redder,
C. R., Reichle, R., Robertson, F. R., Ruddick, A. G., Sienkiewicz, M., and
Woollen, J.: MERRA NASA's Modern-Era Retrospective Analysis for
Research and Applications, J. Climate, 24, 3624–3648,
https://doi.org/10.1175/JCLI-D-11-00015.1, 2011.
Sherwood, S. C., Chae, J.-H., Minnis, P., and McGill, M.: Underestimation
of deep convective cloud tops by thermal imagery, Geophys. Res. Lett.,
31, L11102, https://doi.org/10.1029/2004GL019699, 2004.
Shine, K.: Sources and sinks of zonal momentum in the middle atmosphere
diagnosed using the diabatic circulation, Q. J. Roy.
Meteorol. Soc., 115, 265–292, https://doi.org/10.1002/qj.49711548604, 1989.
Stohl, A., Forster, C., Frank, A., Seibert, P., and Wotawa, G.: Technical
note: The Lagrangian particle dispersion model FLEXPART version 6.2, Atmos.
Chem. Phys., 5, 2461–2474, https://doi.org/10.5194/acp-5-2461-2005, 2005.
Tzella, A. and Legras, B.: A Lagrangian view of convective sources for
transport of air across the Tropical Tropopause Layer: distribution, times
and the radiative influence of clouds, Atmos. Chem. Phys., 11, 12517–12534,
https://doi.org/10.5194/acp-11-12517-2011, 2011.
Vogel, B., Günther, G., Müller, R., Grooß, J.-U., and Riese, M.: Impact of
different Asian source regions on the composition of the Asian monsoon
anticyclone and on the extratropical lowermost stratosphere, Atmos. Chem. Phys., 15, 13699-13716,
https://doi.org/10.5194/acp-15-13699-2015, 2015.
Wang, F., Yang, S., and Wu, T.: Radiation budget biases in AMIP5 models
over the East Asian monsoon region, J. Geophys. Res.-Atmos.,
119, 13400–13426, https://doi.org/10.1002/2014JD022243, 2014.
Wright, J. S., Fu, R., Fueglistaler, S., Liu, Y. S., and Zhang, Y.: The
influence of summertime convection over Southeast Asia on water vapor in
the tropical stratosphere, J. Geophys. Res., 116,
D12302, https://doi.org/10.1029/2010JD015416, 2011.
Wright, J. S. and Fueglistaler, S.: Large differences in reanalyses of
diabatic heating in the tropical upper troposphere and lower stratosphere,
Atmos. Chem. Phys., 13, 9565–9576, https://doi.org/10.5194/acp-13-9565-2013, 2013.
Yang, Q., Fu, Q., and Hu, Y.: Radiative impacts of clouds in the tropical
tropopause layer, J. Geophys. Res., 115, D00H12,
https://doi.org/10.1029/2009JD012393, 2010.
Short summary
Transit properties across the TTL are studied using forward and backward Lagrangian trajectories between cloud tops and the reference surface 380 K. The tropical domain is subdivided into 11 subregions according to the distribution of land and convection. Due to the good agreement between forward and backward statistics, we estimate the contribution of each region to the upward mass flux across the 380 K surface, the vertical distribution of convective sources and of transit times over 2005–2008.
Transit properties across the TTL are studied using forward and backward Lagrangian trajectories...
Altmetrics
Final-revised paper
Preprint