Articles | Volume 17, issue 2
Atmos. Chem. Phys., 17, 965–980, 2017
https://doi.org/10.5194/acp-17-965-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Atmos. Chem. Phys., 17, 965–980, 2017
https://doi.org/10.5194/acp-17-965-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
23 Jan 2017
Research article
| 23 Jan 2017
Biomass burning aerosols and the low-visibility events in Southeast Asia
Hsiang-He Lee et al.
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Peter A. Bogenschutz, Hsiang-He Lee, Qi Tang, and Takanobu Yamaguchi
Geosci. Model Dev., 16, 335–352, https://doi.org/10.5194/gmd-16-335-2023, https://doi.org/10.5194/gmd-16-335-2023, 2023
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Models that are used to simulate and predict climate often have trouble representing specific cloud types, such as stratocumulus, that are particularly thin in the vertical direction. It has been found that increasing the model resolution can help improve this problem. In this paper, we develop a novel framework that increases the horizontal and vertical resolutions only for areas of the globe that contain stratocumulus, hence reducing the model runtime while providing better results.
Hsiang-He Lee and Chien Wang
Atmos. Chem. Phys., 20, 2533–2548, https://doi.org/10.5194/acp-20-2533-2020, https://doi.org/10.5194/acp-20-2533-2020, 2020
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This study has demonstrated how biomass burning activities could affect convective systems in the Maritime Continent by altering cloud microphysics and dynamics. Because near-surface heating from the absorption of fire aerosols can enhance the prevailing wind from the ocean during the daytime and further weaken land breeze and surface convergence at nighttime, it changes the diurnal rainfall intensity, especially those low-level wind patterns associated with the weak westerly (WW) regime.
Benjamin S. Grandey, Daniel Rothenberg, Alexander Avramov, Qinjian Jin, Hsiang-He Lee, Xiaohong Liu, Zheng Lu, Samuel Albani, and Chien Wang
Atmos. Chem. Phys., 18, 15783–15810, https://doi.org/10.5194/acp-18-15783-2018, https://doi.org/10.5194/acp-18-15783-2018, 2018
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Anthropogenic emissions of aerosol particles likely cool the climate system. We investigate the uncertainty in the strength of the cooling effect by exploring the representation of aerosols in a global climate model. We conclude that the specific representation of aerosols in global climate models has important implications for climate modelling. Important factors include the representation of aerosol mixing state, size distribution, and optical properties.
Hsiang-He Lee, Oussama Iraqui, Yefu Gu, Steve Hung-Lam Yim, Apisada Chulakadabba, Adam Yiu-Ming Tonks, Zhengyu Yang, and Chien Wang
Atmos. Chem. Phys., 18, 6141–6156, https://doi.org/10.5194/acp-18-6141-2018, https://doi.org/10.5194/acp-18-6141-2018, 2018
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Our study shows that across ASEAN 50 cities, these model results reveal that 39 % of observed low-visibility days can be explained by either fossil fuel burning or biomass burning emissions alone, a further 20 % by fossil fuel burning alone, a further 8 % by biomass burning alone, and a further 5 % by a combination of fossil fuel burning and biomass burning. The remaining 28 % of observed low-visibility days remains unexplained, likely due to emissions sources that have not been accounted for.
Benjamin S. Grandey, Hsiang-He Lee, and Chien Wang
Atmos. Chem. Phys., 16, 14495–14513, https://doi.org/10.5194/acp-16-14495-2016, https://doi.org/10.5194/acp-16-14495-2016, 2016
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Wildfires emit organic carbon aerosols, small particles suspended in the atmosphere. These aerosols may cool the climate system via interactions with sunlight and clouds. We have used a global climate model to investigate the cooling effects of these aerosols. We find that ignoring interannual variability of the emissions may lead to an overestimation of the cooling effect of the aerosols emitted by fires.
Hsiang-He Lee, Shu-Hua Chen, Michael J. Kleeman, Hongliang Zhang, Steven P. DeNero, and David K. Joe
Atmos. Chem. Phys., 16, 8353–8374, https://doi.org/10.5194/acp-16-8353-2016, https://doi.org/10.5194/acp-16-8353-2016, 2016
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A source-oriented CCN module was implemented in a source-oriented chemistry model to study the effect of aerosol mixing state on fog formation. The fraction of aerosols activating into CCN at a supersaturation of 0.5 % in the Central Valley decreased from 94 % in the internal mixture model to 80 % in the source-oriented model. The internal mixture model predicted greater CCN activation than the source-oriented model due to artificial coating of hydrophobic particles with hygroscopic components.
Lambert Delbeke, Chien Wang, Pierre Tulet, Cyrielle Denjean, Maurin Zouzoua, Nicolas Maury, and Adrien Deroubaix
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-856, https://doi.org/10.5194/acp-2022-856, 2023
Preprint under review for ACP
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Low-Level Stratiform Clouds (LLSC) appear frequently over southern West Africa and during West African Monsoon local and remote aerosol sources (biomass burning aerosol from Central Africa) play a significant role in LLSC life cycle. Based on measurements of DACCIWA campaign, Large Eddy Simulations (LES) were driven using different aerosols scenarios showing indirect effect depends on microphysics and cloud-void spaces. Absorbing particles produced a strong semi-direct effect stabilizing clouds.
Peter A. Bogenschutz, Hsiang-He Lee, Qi Tang, and Takanobu Yamaguchi
Geosci. Model Dev., 16, 335–352, https://doi.org/10.5194/gmd-16-335-2023, https://doi.org/10.5194/gmd-16-335-2023, 2023
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Models that are used to simulate and predict climate often have trouble representing specific cloud types, such as stratocumulus, that are particularly thin in the vertical direction. It has been found that increasing the model resolution can help improve this problem. In this paper, we develop a novel framework that increases the horizontal and vertical resolutions only for areas of the globe that contain stratocumulus, hence reducing the model runtime while providing better results.
Azusa Takeishi and Chien Wang
Atmos. Chem. Phys., 22, 4129–4147, https://doi.org/10.5194/acp-22-4129-2022, https://doi.org/10.5194/acp-22-4129-2022, 2022
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Nanometer- to micrometer-sized particles in the atmosphere, namely aerosols, play a crucial role in cloud formation as cloud droplets form on aerosols. This study uses a weather forecasting model to examine the impacts of a large emission of aerosol particles from biomass burning activities over Southeast Asia. We find that additional cloud droplets brought by fire-emitted particles can lead to taller and more reflective convective clouds with increased rainfall.
Chien Wang
Atmos. Chem. Phys., 21, 13149–13166, https://doi.org/10.5194/acp-21-13149-2021, https://doi.org/10.5194/acp-21-13149-2021, 2021
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Haze caused by abundant atmospheric aerosols has become a serious environmental issue in many countries. An innovative deep-learning machine has been developed to forecast the occurrence of hazes in two Asian megacities (Beijing and Shanghai) and has achieved good overall accuracy. Using this machine, typical regional meteorological and hydrological regimes associated with haze and non-haze events in the two cities have also been, arguably for the first time, successfully categorized.
Hsiang-He Lee and Chien Wang
Atmos. Chem. Phys., 20, 2533–2548, https://doi.org/10.5194/acp-20-2533-2020, https://doi.org/10.5194/acp-20-2533-2020, 2020
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This study has demonstrated how biomass burning activities could affect convective systems in the Maritime Continent by altering cloud microphysics and dynamics. Because near-surface heating from the absorption of fire aerosols can enhance the prevailing wind from the ocean during the daytime and further weaken land breeze and surface convergence at nighttime, it changes the diurnal rainfall intensity, especially those low-level wind patterns associated with the weak westerly (WW) regime.
Qinjian Jin, Benjamin S. Grandey, Daniel Rothenberg, Alexander Avramov, and Chien Wang
Atmos. Chem. Phys., 18, 16793–16808, https://doi.org/10.5194/acp-18-16793-2018, https://doi.org/10.5194/acp-18-16793-2018, 2018
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International shipping emissions (ISE) can influence the global radiation budget. Using an Earth system model, we derive a significant global cloud radiative effect (CRE) of ISE (−0.153 W m−2) when using current emissions. This CRE would become weaker (−0.001 W m−2) if a more stringent regulation were adopted. The CRE would achieve a significant enhancement when a lower DMS emission is prescribed. These findings suggest a reevaluation of the ISE-induced CRE with consideration of DMS variability.
Benjamin S. Grandey, Daniel Rothenberg, Alexander Avramov, Qinjian Jin, Hsiang-He Lee, Xiaohong Liu, Zheng Lu, Samuel Albani, and Chien Wang
Atmos. Chem. Phys., 18, 15783–15810, https://doi.org/10.5194/acp-18-15783-2018, https://doi.org/10.5194/acp-18-15783-2018, 2018
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Anthropogenic emissions of aerosol particles likely cool the climate system. We investigate the uncertainty in the strength of the cooling effect by exploring the representation of aerosols in a global climate model. We conclude that the specific representation of aerosols in global climate models has important implications for climate modelling. Important factors include the representation of aerosol mixing state, size distribution, and optical properties.
Daniel Rothenberg, Alexander Avramov, and Chien Wang
Atmos. Chem. Phys., 18, 7961–7983, https://doi.org/10.5194/acp-18-7961-2018, https://doi.org/10.5194/acp-18-7961-2018, 2018
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Estimates of how much the particles we emit into the atmosphere cool the climate depend on how those particles influence the relative number of cloud droplets. Those estimates are strongly influenced by how many droplets a given climate model predicts under clean conditions, even more so than how much that human emissions increase droplet concentrations. Because of this, observations of particles influencing clouds in clean conditions could help constrain their climate-cooling potential.
Hsiang-He Lee, Oussama Iraqui, Yefu Gu, Steve Hung-Lam Yim, Apisada Chulakadabba, Adam Yiu-Ming Tonks, Zhengyu Yang, and Chien Wang
Atmos. Chem. Phys., 18, 6141–6156, https://doi.org/10.5194/acp-18-6141-2018, https://doi.org/10.5194/acp-18-6141-2018, 2018
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Our study shows that across ASEAN 50 cities, these model results reveal that 39 % of observed low-visibility days can be explained by either fossil fuel burning or biomass burning emissions alone, a further 20 % by fossil fuel burning alone, a further 8 % by biomass burning alone, and a further 5 % by a combination of fossil fuel burning and biomass burning. The remaining 28 % of observed low-visibility days remains unexplained, likely due to emissions sources that have not been accounted for.
Sarvesh Garimella, Daniel A. Rothenberg, Martin J. Wolf, Robert O. David, Zamin A. Kanji, Chien Wang, Michael Rösch, and Daniel J. Cziczo
Atmos. Chem. Phys., 17, 10855–10864, https://doi.org/10.5194/acp-17-10855-2017, https://doi.org/10.5194/acp-17-10855-2017, 2017
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This study investigates systematic and variable low bias in the measurement of ice nucleating particle concentration using continuous flow diffusion chambers. We find that non-ideal instrument behavior exposes particles to different humidities and/or temperatures than predicted from theory. We use a machine learning approach to quantify and minimize the uncertainty associated with this measurement bias.
Daniel Rothenberg and Chien Wang
Geosci. Model Dev., 10, 1817–1833, https://doi.org/10.5194/gmd-10-1817-2017, https://doi.org/10.5194/gmd-10-1817-2017, 2017
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Climate models include descriptions of how cloud droplets form from particles in the atmosphere. We have developed an efficient parameterization of this process by building an emulator of a detailed model, which can accurately predict cloud droplet number concentrations and potentially include additional physics and chemistry. We further show that using different parameterizations could influence droplet number estimates in global models and their aerosol indirect effect on climate.
Benjamin S. Grandey, Hsiang-He Lee, and Chien Wang
Atmos. Chem. Phys., 16, 14495–14513, https://doi.org/10.5194/acp-16-14495-2016, https://doi.org/10.5194/acp-16-14495-2016, 2016
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Wildfires emit organic carbon aerosols, small particles suspended in the atmosphere. These aerosols may cool the climate system via interactions with sunlight and clouds. We have used a global climate model to investigate the cooling effects of these aerosols. We find that ignoring interannual variability of the emissions may lead to an overestimation of the cooling effect of the aerosols emitted by fires.
Graydon Snider, Crystal L. Weagle, Kalaivani K. Murdymootoo, Amanda Ring, Yvonne Ritchie, Emily Stone, Ainsley Walsh, Clement Akoshile, Nguyen Xuan Anh, Rajasekhar Balasubramanian, Jeff Brook, Fatimah D. Qonitan, Jinlu Dong, Derek Griffith, Kebin He, Brent N. Holben, Ralph Kahn, Nofel Lagrosas, Puji Lestari, Zongwei Ma, Amit Misra, Leslie K. Norford, Eduardo J. Quel, Abdus Salam, Bret Schichtel, Lior Segev, Sachchida Tripathi, Chien Wang, Chao Yu, Qiang Zhang, Yuxuan Zhang, Michael Brauer, Aaron Cohen, Mark D. Gibson, Yang Liu, J. Vanderlei Martins, Yinon Rudich, and Randall V. Martin
Atmos. Chem. Phys., 16, 9629–9653, https://doi.org/10.5194/acp-16-9629-2016, https://doi.org/10.5194/acp-16-9629-2016, 2016
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We examine the chemical composition of fine particulate matter (PM2.5) collected on filters at traditionally undersampled, globally dispersed urban locations. Several PM2.5 chemical components (e.g. ammonium sulfate, ammonium nitrate, and black carbon) vary by more than an order of magnitude between sites while aerosol hygroscopicity varies by a factor of 2. Enhanced anthropogenic dust fractions in large urban areas are apparent from high Zn : Al ratios.
Matthew J. Alvarado, Chantelle R. Lonsdale, Helen L. Macintyre, Huisheng Bian, Mian Chin, David A. Ridley, Colette L. Heald, Kenneth L. Thornhill, Bruce E. Anderson, Michael J. Cubison, Jose L. Jimenez, Yutaka Kondo, Lokesh K. Sahu, Jack E. Dibb, and Chien Wang
Atmos. Chem. Phys., 16, 9435–9455, https://doi.org/10.5194/acp-16-9435-2016, https://doi.org/10.5194/acp-16-9435-2016, 2016
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Understanding the scattering and absorption of light by aerosols is necessary for understanding air quality and climate change. We used data from the 2008 ARCTAS campaign to evaluate aerosol optical property models using a closure methodology that separates errors in these models from other errors in aerosol emissions, chemistry, or transport. We find that the models on average perform reasonably well, and make suggestions for how remaining biases could be reduced.
Hsiang-He Lee, Shu-Hua Chen, Michael J. Kleeman, Hongliang Zhang, Steven P. DeNero, and David K. Joe
Atmos. Chem. Phys., 16, 8353–8374, https://doi.org/10.5194/acp-16-8353-2016, https://doi.org/10.5194/acp-16-8353-2016, 2016
Short summary
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A source-oriented CCN module was implemented in a source-oriented chemistry model to study the effect of aerosol mixing state on fog formation. The fraction of aerosols activating into CCN at a supersaturation of 0.5 % in the Central Valley decreased from 94 % in the internal mixture model to 80 % in the source-oriented model. The internal mixture model predicted greater CCN activation than the source-oriented model due to artificial coating of hydrophobic particles with hygroscopic components.
Related subject area
Subject: Aerosols | Research Activity: Atmospheric Modelling | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
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Chandan Sarangi, Yun Qian, L. Ruby Leung, Yang Zhang, Yufei Zou, and Yuhang Wang
Atmos. Chem. Phys., 23, 1769–1783, https://doi.org/10.5194/acp-23-1769-2023, https://doi.org/10.5194/acp-23-1769-2023, 2023
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We show that for air quality, the densely populated eastern US may see even larger impacts of wildfires due to long-distance smoke transport and associated positive climatic impacts, partially compensating the improvements from regulations on anthropogenic emissions. This study highlights the tension between natural and anthropogenic contributions and the non-local nature of air pollution that complicate regulatory strategies for improving future regional air quality for human health.
Rémy Lapere, Nicolás Huneeus, Sylvain Mailler, Laurent Menut, and Florian Couvidat
Atmos. Chem. Phys., 23, 1749–1768, https://doi.org/10.5194/acp-23-1749-2023, https://doi.org/10.5194/acp-23-1749-2023, 2023
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Glaciers in the Andes of central Chile are shrinking rapidly in response to global warming. This melting is accelerated by the deposition of opaque particles onto snow and ice. In this work, model simulations quantify typical deposition rates of soot on glaciers in summer and winter months and show that the contribution of emissions from Santiago is not as high as anticipated. Additionally, the combination of regional- and local-scale meteorology explains the seasonality in deposition.
Ju Liang and Jim Haywood
Atmos. Chem. Phys., 23, 1687–1703, https://doi.org/10.5194/acp-23-1687-2023, https://doi.org/10.5194/acp-23-1687-2023, 2023
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The recent record-breaking flood events in China during the summer of 2021 highlight the importance of mitigating the risks from future changes in high-impact weather systems under global warming. Based on a state-of-the-art Earth system model, we demonstrate a pilot study on the responses of atmospheric rivers and extreme precipitation over East Asia to anthropogenically induced climate warming and an unconventional mitigation strategy – stratospheric aerosol injection.
Azad Madhu, Myoseon Jang, and David Deacon
Atmos. Chem. Phys., 23, 1661–1675, https://doi.org/10.5194/acp-23-1661-2023, https://doi.org/10.5194/acp-23-1661-2023, 2023
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SOA formation is simulated using the UNIPAR model for series of linear alkanes. The inclusion of autoxidation reactions within the explicit gas mechanisms of C9–C12 was found to significantly improve predictions. Available product distributions were extrapolated with an incremental volatility coefficient (IVC) to predict SOA formation of alkanes without explicit mechanisms. These product distributions were used to simulate SOA formation from C13 and C15 and had good agreement with chamber data.
Jianbing Jin, Bas Henzing, and Arjo Segers
Atmos. Chem. Phys., 23, 1641–1660, https://doi.org/10.5194/acp-23-1641-2023, https://doi.org/10.5194/acp-23-1641-2023, 2023
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Aerosol models and satellite retrieval algorithms rely on different aerosol size assumptions. In practice, differences between simulations and observations do not always reflect the difference in aerosol amount. To avoid inconsistencies, we designed a hybrid assimilation approach. Different from a standard aerosol optical depth (AOD) assimilation that directly assimilates AODs, the hybrid one estimates aerosol size parameters by assimilating Ängström observations before assimilating the AODs.
Je-Yun Chun, Robert Wood, Peter Blossey, and Sarah J. Doherty
Atmos. Chem. Phys., 23, 1345–1368, https://doi.org/10.5194/acp-23-1345-2023, https://doi.org/10.5194/acp-23-1345-2023, 2023
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We investigate the impact of injected aerosol on subtropical low marine clouds under a variety of meteorological conditions using high-resolution model simulations. This study illustrates processes perturbed by aerosol injections and their impact on cloud properties (e.g., cloud number concentration, thickness, and cover). We show that those responses are highly sensitive to background meteorological conditions, such as precipitation, and background cloud properties.
Nora L. S. Fahrenbach and Massimo A. Bollasina
Atmos. Chem. Phys., 23, 877–894, https://doi.org/10.5194/acp-23-877-2023, https://doi.org/10.5194/acp-23-877-2023, 2023
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We studied the monthly-scale climate response to COVID-19 aerosol emission reductions during January–May 2020 using climate models. Our results show global temperature and rainfall anomalies driven by circulation changes. The climate patterns reverse polarity from JF to MAM due to a shift in the main SO2 reduction region from China to India. This real-life example of rapid climate adjustments to abrupt, regional aerosol emission reduction has large implications for future climate projections.
Seoung Soo Lee, Junshik Um, Won Jun Choi, Kyung-Ja Ha, Chang Hoon Jung, Jianping Guo, and Youtong Zheng
Atmos. Chem. Phys., 23, 273–286, https://doi.org/10.5194/acp-23-273-2023, https://doi.org/10.5194/acp-23-273-2023, 2023
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This paper elaborates on process-level mechanisms regarding how the interception of radiation by aerosols interacts with the surface heat fluxes and atmospheric instability in warm cumulus clouds. This paper elucidates how these mechanisms vary with the location or altitude of an aerosol layer. This elucidation indicates that the location of aerosol layers should be taken into account for parameterizations of aerosol–cloud interactions.
Meredith Schervish and Manabu Shiraiwa
Atmos. Chem. Phys., 23, 221–233, https://doi.org/10.5194/acp-23-221-2023, https://doi.org/10.5194/acp-23-221-2023, 2023
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Secondary organic aerosols (SOAs) can exhibit complex non-ideal behavior and adopt an amorphous semisolid state. We simulate condensation of semi-volatile compounds into a phase-separated particle to investigate the effect of non-ideality and particle phase state on the equilibration timescale of SOA partitioning. Our results provide useful insights into the interpretation of experimental observations and the description and treatment of SOA in aerosol models.
Christof G. Beer, Johannes Hendricks, and Mattia Righi
Atmos. Chem. Phys., 22, 15887–15907, https://doi.org/10.5194/acp-22-15887-2022, https://doi.org/10.5194/acp-22-15887-2022, 2022
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Ice-nucleating particles (INPs) have important influences on cirrus clouds and the climate system; however, their global atmospheric distribution in the cirrus regime is still very uncertain. We present a global climatology of INPs under cirrus conditions derived from model simulations, considering the mineral dust, soot, crystalline ammonium sulfate, and glassy organics INP types. The comparison of respective INP concentrations indicates the large importance of ammonium sulfate particles.
Mykhailo Savenets, Larysa Pysarenko, Svitlana Krakovska, Alexander Mahura, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 15777–15791, https://doi.org/10.5194/acp-22-15777-2022, https://doi.org/10.5194/acp-22-15777-2022, 2022
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The paper explores the spatio-temporal variability of black carbon during a wildfire in August 2010, with a focus on Ukraine. As a research tool, the seamless Enviro-HIRLAM modelling system is used for investigating the atmospheric transport of aerosol particles emitted by wildfires from remote and local sources. The results of this study improve our understanding of the physical and chemical processes and the interactions of aerosols in the atmosphere.
Huilin Huang, Yun Qian, Ye Liu, Cenlin He, Jianyu Zheng, Zhibo Zhang, and Antonis Gkikas
Atmos. Chem. Phys., 22, 15469–15488, https://doi.org/10.5194/acp-22-15469-2022, https://doi.org/10.5194/acp-22-15469-2022, 2022
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Using a clustering method developed in the field of artificial neural networks, we identify four typical dust transport patterns across the Sierra Nevada, associated with the mesoscale and regional-scale wind circulations. Our results highlight the connection between dust transport and dominant weather patterns, which can be used to understand dust transport in a changing climate.
Anbao Zhu, Haiming Xu, Jiechun Deng, Jing Ma, and Shaofeng Hua
Atmos. Chem. Phys., 22, 15425–15447, https://doi.org/10.5194/acp-22-15425-2022, https://doi.org/10.5194/acp-22-15425-2022, 2022
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This study demonstrates the instant and delayed effects of biomass burning (BB) aerosols on precipitation over the Indochina Peninsula (ICP). The convection suppression due to the BB aerosol-induced stabilized atmosphere dominates over the favorable water-vapor condition induced by large-scale circulation responses, leading to an overall reduced precipitation in March, while the delayed effect promotes precipitation from early April to mid April due to the anomalous atmospheric circulations.
Wenjie Zhang, Hong Wang, Xiaoye Zhang, Liping Huang, Yue Peng, Zhaodong Liu, Xiao Zhang, and Huizheng Che
Atmos. Chem. Phys., 22, 15207–15221, https://doi.org/10.5194/acp-22-15207-2022, https://doi.org/10.5194/acp-22-15207-2022, 2022
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Aerosol–cloud interaction (ACI) is first implemented in the atmospheric chemistry system GRAPES_Meso5.1/CUACE. ACI can improve the simulated cloud, temperature, and precipitation under haze pollution conditions in Jing-Jin-Ji in China. This paper demonstrates the critical role of ACI in current numerical weather prediction over the severely polluted region.
Santeri Tuovinen, Runlong Cai, Veli-Matti Kerminen, Jingkun Jiang, Chao Yan, Markku Kulmala, and Jenni Kontkanen
Atmos. Chem. Phys., 22, 15071–15091, https://doi.org/10.5194/acp-22-15071-2022, https://doi.org/10.5194/acp-22-15071-2022, 2022
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We compare observed survival probabilities of atmospheric particles from Beijing, China, with survival probabilities based on analytical formulae and model simulations. We find observed survival probabilities under polluted conditions at smaller sizes to be higher, while at larger sizes they are lower than or similar to theoretical survival probabilities. Uncertainties in condensation sink and growth rate are unlikely to explain higher-than-predicted survival probabilities at smaller sizes.
Stephanie Woodward, Alistair A. Sellar, Yongming Tang, Marc Stringer, Andrew Yool, Eddy Robertson, and Andy Wiltshire
Atmos. Chem. Phys., 22, 14503–14528, https://doi.org/10.5194/acp-22-14503-2022, https://doi.org/10.5194/acp-22-14503-2022, 2022
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We describe the dust scheme in the UKESM1 Earth system model and show generally good agreement with observations. Comparing with the closely related HadGEM3-GC3.1 model, we show that dust differences are not only due to inter-model differences but also to the dust size distribution. Under climate change, HadGEM3-GC3.1 dust hardly changes, but UKESM1 dust decreases because that model includes the vegetation response which, in our models, has a bigger impact on dust than climate change itself.
Yang Yang, Liangying Zeng, Hailong Wang, Pinya Wang, and Hong Liao
Atmos. Chem. Phys., 22, 14489–14502, https://doi.org/10.5194/acp-22-14489-2022, https://doi.org/10.5194/acp-22-14489-2022, 2022
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Using an aerosol–climate model, dust pollution in China affected by different spatial and temporal types of El Niño are examined. Both eastern and central Pacific El Niño and short-duration El Niño increase winter dust concentrations over northern China, while long-duration El Niño decreases concentrations. Only long-duration El Niño events can significantly affect dust over China in the following spring. This study has profound implications for air pollution control and dust storm prediction.
Robin Stevens, Andrei Ryjkov, Mahtab Majdzadeh, and Ashu Dastoor
Atmos. Chem. Phys., 22, 13527–13549, https://doi.org/10.5194/acp-22-13527-2022, https://doi.org/10.5194/acp-22-13527-2022, 2022
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Absorbing particles like black carbon can be coated with other matter. How much radiation these particles absorb depends on the coating thickness. The removal of these particles by clouds and rain depends on the coating composition. These effects are important for both climate and air quality. We implement a more detailed representation of these particles in an air quality model which accounts for both coating thickness and composition. We find a significant effect on particle concentrations.
Fan Wang, Gregory R. Carmichael, Jing Wang, Bin Chen, Bo Huang, Yuguo Li, Yuanjian Yang, and Meng Gao
Atmos. Chem. Phys., 22, 13341–13353, https://doi.org/10.5194/acp-22-13341-2022, https://doi.org/10.5194/acp-22-13341-2022, 2022
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Unprecedented urbanization in China has led to serious urban heat island (UHI) issues, exerting intense heat stress on urban residents. We find diverse influences of aerosol pollution on urban heat island intensity (UHII) under different circulations. Our results also highlight the role of black carbon in aggravating UHI, especially during nighttime. It could thus be targeted for cooperative management of heat islands and aerosol pollution.
Qianqian Song, Zhibo Zhang, Hongbin Yu, Jasper F. Kok, Claudia Di Biagio, Samuel Albani, Jianyu Zheng, and Jiachen Ding
Atmos. Chem. Phys., 22, 13115–13135, https://doi.org/10.5194/acp-22-13115-2022, https://doi.org/10.5194/acp-22-13115-2022, 2022
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This study developed a dataset that enables us to efficiently calculate dust direct radiative effect (DRE, i.e., cooling or warming our planet) for any given dust size distribution in addition to three sets of dust mineral components and two dust shapes. We demonstrate and validate the method of using this dataset to calculate dust DRE. Moreover, using this dataset we found that dust mineral composition is a more important factor in determining dust DRE than dust size and shape.
Eleni Drakaki, Vassilis Amiridis, Alexandra Tsekeri, Antonis Gkikas, Emmanouil Proestakis, Sotirios Mallios, Stavros Solomos, Christos Spyrou, Eleni Marinou, Claire L. Ryder, Demetri Bouris, and Petros Katsafados
Atmos. Chem. Phys., 22, 12727–12748, https://doi.org/10.5194/acp-22-12727-2022, https://doi.org/10.5194/acp-22-12727-2022, 2022
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State-of-the-art atmospheric dust models have limitations in accounting for a realistic dust size distribution (emission, transport). We modify the parameterization of the mineral dust cycle by including particles with diameter >20 μm, as indicated by observations over deserts. Moreover, we investigate the effects of reduced settling velocities of dust particles. Model results are evaluated using airborne and spaceborne dust measurements above Cabo Verde.
Chenguang Tian, Xu Yue, Jun Zhu, Hong Liao, Yang Yang, Yadong Lei, Xinyi Zhou, Hao Zhou, Yimian Ma, and Yang Cao
Atmos. Chem. Phys., 22, 12353–12366, https://doi.org/10.5194/acp-22-12353-2022, https://doi.org/10.5194/acp-22-12353-2022, 2022
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We quantify the impacts of fire aerosols on climate through direct, indirect, and albedo effects. In atmosphere-only simulations, we find global fire aerosols cause surface cooling and rainfall inhibition over many land regions. These fast atmospheric perturbations further lead to a reduction in regional leaf area index and lightning activities. By considering the feedback of fire aerosols on humidity, lightning, and leaf area index, we predict a slight reduction in fire emissions.
Yanxing Wu, Run Liu, Yanzi Li, Junjie Dong, Zhijiong Huang, Junyu Zheng, and Shaw Chen Liu
Atmos. Chem. Phys., 22, 11945–11955, https://doi.org/10.5194/acp-22-11945-2022, https://doi.org/10.5194/acp-22-11945-2022, 2022
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Multiple linear regression (MLR) analyses often interpret the correlation coefficient (r2) as the contribution of an independent variable to the dependent variable. Since a good correlation does not imply a causal relationship, we propose that r2 should be interpreted as the maximum possible contribution. Moreover, MLR results are sensitive to the length of time analyzed; long-term analysis gives a more accurate assessment because of its additional constraints.
Mengying Li, Shaocai Yu, Xue Chen, Zhen Li, Yibo Zhang, Zhe Song, Weiping Liu, Pengfei Li, Xiaoye Zhang, Meigen Zhang, Yele Sun, Zirui Liu, Caiping Sun, Jingkun Jiang, Shuxiao Wang, Benjamin N. Murphy, Kiran Alapaty, Rohit Mathur, Daniel Rosenfeld, and John H. Seinfeld
Atmos. Chem. Phys., 22, 11845–11866, https://doi.org/10.5194/acp-22-11845-2022, https://doi.org/10.5194/acp-22-11845-2022, 2022
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This study constructed an emission inventory of condensable particulate matter (CPM) in China with a focus on organic aerosols (OAs), based on collected CPM emission information. The results show that OA emissions are enhanced twofold for the years 2014 and 2017 after the inclusion of CPM in the new inventory. Sensitivity cases demonstrated the significant contributions of CPM emissions from stationary combustion and mobile sources to primary, secondary, and total OA concentrations.
Petri Räisänen, Joonas Merikanto, Risto Makkonen, Mikko Savolahti, Alf Kirkevåg, Maria Sand, Øyvind Seland, and Antti-Ilari Partanen
Atmos. Chem. Phys., 22, 11579–11602, https://doi.org/10.5194/acp-22-11579-2022, https://doi.org/10.5194/acp-22-11579-2022, 2022
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A climate model is used to evaluate how the radiative forcing (RF) associated with black carbon (BC) emissions depends on the latitude, longitude, and seasonality of emissions. It is found that both the direct RF (BC absorption of solar radiation in air) and snow RF (BC absorption in snow/ice) depend strongly on the emission region and season. The results suggest that, for a given mass of BC emitted, climatic impacts are likely to be largest for high-latitude emissions due to the large snow RF.
Xipeng Jin, Xuhui Cai, Mingyuan Yu, Yu Song, Xuesong Wang, Hongsheng Zhang, and Tong Zhu
Atmos. Chem. Phys., 22, 11409–11427, https://doi.org/10.5194/acp-22-11409-2022, https://doi.org/10.5194/acp-22-11409-2022, 2022
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Meteorological discontinuities in the vertical direction define the lowest atmosphere as the boundary layer, while in the horizontal direction it identifies the contrast zone as the internal boundary. Both of them determine the polluted air mass dimension over the North China Plain. This study reveals the boundary layer structures under three categories of internal boundaries, modified by thermal, dynamical, and blending effects. It provides a new insight to understand regional pollution.
Lichao Yang, Wansuo Duan, Zifa Wang, and Wenyi Yang
Atmos. Chem. Phys., 22, 11429–11453, https://doi.org/10.5194/acp-22-11429-2022, https://doi.org/10.5194/acp-22-11429-2022, 2022
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The initial meteorological state has a great impact on PM2.5 forecasts. Assimilating additional observations is an effective way to improve the accuracy of the initial meteorological state. Here we used an advanced optimization approach to identify where we should preferentially place the meteorological observations associated with PM2.5 forecasts in the Beijing–Tianjin–Hebei region of China. We provide evidence that the target observation strategy is effective for improving PM2.5 forecasts.
Anthony C. Jones, Adrian Hill, John Hemmings, Pascal Lemaitre, Arnaud Quérel, Claire L. Ryder, and Stephanie Woodward
Atmos. Chem. Phys., 22, 11381–11407, https://doi.org/10.5194/acp-22-11381-2022, https://doi.org/10.5194/acp-22-11381-2022, 2022
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As raindrops fall to the ground, they capture aerosol (i.e. below-cloud scavenging or BCS). Many different BCS schemes are available to climate models, and it is unclear what the impact of selecting one scheme over another is. Here, various BCS models are outlined and then applied to mineral dust in climate model simulations. We find that dust concentrations are highly sensitive to the BCS scheme, with dust atmospheric lifetimes ranging from 5 to 44 d.
Peng Wang, Ruhan Zhang, Shida Sun, Meng Gao, Bo Zheng, Dan Zhang, Yangli Zhang, Gregory R. Carmichael, and Hongliang Zhang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-577, https://doi.org/10.5194/acp-2022-577, 2022
Revised manuscript accepted for ACP
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In China, vehicles have jumped significantly in the recent decade. This caused severe traffic congestion and aggravated air pollution. In this study, we developed a new temporal-allocation approach to quantify the impacts of traffic congestion. We found that traffic congestion worsens air quality and health burden across China, especially in the urban clusters. More effective and comprehensive vehicle emission control policies should be implemented to improve air quality in China.
Zhicong Yin, Mingkeng Duan, Yuyan Li, Tianbao Xu, and Huijun Wang
Atmos. Chem. Phys., 22, 11173–11185, https://doi.org/10.5194/acp-22-11173-2022, https://doi.org/10.5194/acp-22-11173-2022, 2022
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The PM2.5 concentration has been greatly reduced in recent years in China and has entered a crucial stage that required fine seasonal prediction. However, there is still no study aimed at predicting gridded PM2.5 concentration. A model for seasonal prediction of gridded winter PM2.5 concentration in the east of China was developed by analyzing the contributions of emissions and climate variability, which could provide scientific support for air pollution control at the regional and city levels.
Qirui Zhong, Nick Schutgens, Guido van der Werf, Twan van Noije, Kostas Tsigaridis, Susanne E. Bauer, Tero Mielonen, Alf Kirkevåg, Øyvind Seland, Harri Kokkola, Ramiro Checa-Garcia, David Neubauer, Zak Kipling, Hitoshi Matsui, Paul Ginoux, Toshihiko Takemura, Philippe Le Sager, Samuel Rémy, Huisheng Bian, Mian Chin, Kai Zhang, Jialei Zhu, Svetlana G. Tsyro, Gabriele Curci, Anna Protonotariou, Ben Johnson, Joyce E. Penner, Nicolas Bellouin, Ragnhild B. Skeie, and Gunnar Myhre
Atmos. Chem. Phys., 22, 11009–11032, https://doi.org/10.5194/acp-22-11009-2022, https://doi.org/10.5194/acp-22-11009-2022, 2022
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Aerosol optical depth (AOD) errors for biomass burning aerosol (BBA) are evaluated in 18 global models against satellite datasets. Notwithstanding biases in satellite products, they allow model evaluations. We observe large and diverse model biases due to errors in BBA. Further interpretations of AOD diversities suggest large biases exist in key processes for BBA which require better constraining. These results can contribute to further model improvement and development.
Marje Prank, Juha Tonttila, Jaakko Ahola, Harri Kokkola, Thomas Kühn, Sami Romakkaniemi, and Tomi Raatikainen
Atmos. Chem. Phys., 22, 10971–10992, https://doi.org/10.5194/acp-22-10971-2022, https://doi.org/10.5194/acp-22-10971-2022, 2022
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Aerosols and clouds persist as the dominant sources of uncertainty in climate projections. In this modelling study, we investigate the role of marine aerosols in influencing the lifetime of low-level clouds. Our high resolution simulations show that sea spray can both extend and shorten the lifetime of the cloud layer depending on the model setup. The impact of the primary marine organics is relatively limited while secondary aerosol from monoterpenes can have larger impact.
Roger Teoh, Ulrich Schumann, Edward Gryspeerdt, Marc Shapiro, Jarlath Molloy, George Koudis, Christiane Voigt, and Marc E. J. Stettler
Atmos. Chem. Phys., 22, 10919–10935, https://doi.org/10.5194/acp-22-10919-2022, https://doi.org/10.5194/acp-22-10919-2022, 2022
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Aircraft condensation trails (contrails) contribute to over half of the climate forcing attributable to aviation. This study uses historical air traffic and weather data to simulate contrails in the North Atlantic over 5 years, from 2016 to 2021. We found large intra- and inter-year variability in contrail radiative forcing and observed a 66 % reduction due to COVID-19. Most warming contrails predominantly result from night-time flights in winter.
Haochi Che, Philip Stier, Duncan Watson-Parris, Hamish Gordon, and Lucia Deaconu
Atmos. Chem. Phys., 22, 10789–10807, https://doi.org/10.5194/acp-22-10789-2022, https://doi.org/10.5194/acp-22-10789-2022, 2022
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Extensive stratocumulus clouds over the south-eastern Atlantic (SEA) can lead to a cooling effect on the climate. A key pathway by which aerosols affect cloud properties is by acting as cloud condensation nuclei (CCN). Here, we investigated the source attribution of CCN in the SEA as well as the cloud responses. Our results show that aerosol nucleation contributes most to CCN in the marine boundary layer. In terms of emissions, anthropogenic sources contribute most to the CCN and cloud droplets.
Marios Chatziparaschos, Nikos Daskalakis, Stelios Myriokefalitakis, Nikos Kalivitis, Athanasios Nenes, Maria Gonçalves Ageitos, Montserrat Costa-Surós, Carlos Pérez García-Pando, Medea Zanoli, Mihalis Vrekoussis, and Maria Kanakidou
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-551, https://doi.org/10.5194/acp-2022-551, 2022
Revised manuscript accepted for ACP
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Ice formation is enabled by Ice Nucleating Particles (INP) at higher temperatures than homogeneous formation and can profoundly affect the properties of clouds. Our global model results show that additionally to k-feldspar dust mineral that is globally the most important INP precursor, quartz, which is abundant in mineral dust, can be regionally significant, affecting different cloud level regimes (low-level clouds) than K-feldspar (mid-level clouds).
Aditya Kumar, R. Bradley Pierce, Ravan Ahmadov, Gabriel Pereira, Saulo Freitas, Georg Grell, Chris Schmidt, Allen Lenzen, Joshua P. Schwarz, Anne E. Perring, Joseph M. Katich, John Hair, Jose L. Jimenez, Pedro Campuzano-Jost, and Hongyu Guo
Atmos. Chem. Phys., 22, 10195–10219, https://doi.org/10.5194/acp-22-10195-2022, https://doi.org/10.5194/acp-22-10195-2022, 2022
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We use the WRF-Chem model with new implementations of GOES-16 wildfire emissions and plume rise based on fire radiative power (FRP) to interpret aerosol observations during the 2019 NASA–NOAA FIREX-AQ field campaign and perform model evaluations. The model shows significant improvements in simulating the variety of aerosol loading environments sampled during FIREX-AQ. Our results also highlight the importance of accurate wildfire diurnal cycle and aerosol chemical mechanisms in models.
Golnaz Roudsari, Olli H. Pakarinen, Bernhard Reischl, and Hanna Vehkamäki
Atmos. Chem. Phys., 22, 10099–10114, https://doi.org/10.5194/acp-22-10099-2022, https://doi.org/10.5194/acp-22-10099-2022, 2022
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We use atomistic simulations to study heterogeneous ice nucleation on silver iodide surfaces in slit and wedge geometries at low supercooling which serve as a model of irregularities on real atmospheric aerosol particle surfaces. The revealed microscopic ice nucleation mechanisms in confined geometries strongly support the experimental evidence for the importance of surface features such as cracks or pits functioning as active sites for ice nucleation in the atmosphere.
Carlton Xavier, Metin Baykara, Robin Wollesen de Jonge, Barbara Altstädter, Petri Clusius, Ville Vakkari, Roseline Thakur, Lisa Beck, Silvia Becagli, Mirko Severi, Rita Traversi, Radovan Krejci, Peter Tunved, Mauro Mazzola, Birgit Wehner, Mikko Sipilä, Markku Kulmala, Michael Boy, and Pontus Roldin
Atmos. Chem. Phys., 22, 10023–10043, https://doi.org/10.5194/acp-22-10023-2022, https://doi.org/10.5194/acp-22-10023-2022, 2022
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The focus of this work is to study and improve our understanding of processes involved in the formation and growth of new particles in a remote Arctic marine environment. We run the 1D model ADCHEM along air mass trajectories arriving at Ny-Ålesund in May 2018. The model finds that ion-mediated H2SO4–NH3 nucleation can explain the observed new particle formation at Ny-Ålesund. The growth of particles is driven via H2SO4 condensation and formation of methane sulfonic acid in the aqueous phase.
Kai Zhang, Wentao Zhang, Hui Wan, Philip J. Rasch, Steven J. Ghan, Richard C. Easter, Xiangjun Shi, Yong Wang, Hailong Wang, Po-Lun Ma, Shixuan Zhang, Jian Sun, Susannah M. Burrows, Manish Shrivastava, Balwinder Singh, Yun Qian, Xiaohong Liu, Jean-Christophe Golaz, Qi Tang, Xue Zheng, Shaocheng Xie, Wuyin Lin, Yan Feng, Minghuai Wang, Jin-Ho Yoon, and L. Ruby Leung
Atmos. Chem. Phys., 22, 9129–9160, https://doi.org/10.5194/acp-22-9129-2022, https://doi.org/10.5194/acp-22-9129-2022, 2022
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Here we analyze the effective aerosol forcing simulated by E3SM version 1 using both century-long free-running and short nudged simulations. The aerosol forcing in E3SMv1 is relatively large compared to other models, mainly due to the large indirect aerosol effect. Aerosol-induced changes in liquid and ice cloud properties in E3SMv1 have a strong correlation. The aerosol forcing estimates in E3SMv1 are sensitive to the parameterization changes in both liquid and ice cloud processes.
Seoung Soo Lee, Jinho Choi, Goun Kim, Kyung-Ja Ha, Kyong-Hwan Seo, Chang Hoon Jung, Junshik Um, Youtong Zheng, Jianping Guo, Sang-Keun Song, Yun Gon Lee, and Nobuyuki Utsumi
Atmos. Chem. Phys., 22, 9059–9081, https://doi.org/10.5194/acp-22-9059-2022, https://doi.org/10.5194/acp-22-9059-2022, 2022
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This study investigates how aerosols affect clouds and precipitation and how the aerosol effects vary with varying types of clouds that are characterized by cloud depth in two metropolitan areas in East Asia. As cloud depth increases, the enhancement of precipitation amount transitions to no changes in precipitation amount with increasing aerosol concentrations. This indicates that cloud depth needs to be considered for a comprehensive understanding of aerosol-cloud interactions.
Karine Sartelet, Youngseob Kim, Florian Couvidat, Maik Merkel, Tuukka Petäjä, Jean Sciare, and Alfred Wiedensohler
Atmos. Chem. Phys., 22, 8579–8596, https://doi.org/10.5194/acp-22-8579-2022, https://doi.org/10.5194/acp-22-8579-2022, 2022
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A methodology is defined to estimate number emissions from an inventory providing mass emissions. Number concentrations are simulated over Greater Paris using different nucleation parameterisations (binary, ternary involving sulfuric acid and ammonia, and heteromolecular involving sulfuric acid and extremely low-volatility organics, ELVOCs). The comparisons show that ternary nucleation may not be a dominant process for new particle formation in cities, but they stress the role of ELVOCs.
Zhaochen Liu, Xianmei Lang, and Dabang Jiang
Atmos. Chem. Phys., 22, 7667–7680, https://doi.org/10.5194/acp-22-7667-2022, https://doi.org/10.5194/acp-22-7667-2022, 2022
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Stratospheric aerosol intervention geoengineering is considered a potential means to counteract global warming. Here the impact of stratospheric aerosol intervention geoengineering on surface air temperature over China and related physical processes are investigated. Results show that the increased stratospheric aerosols cause surface cooling over China. The temperature responses vary with models, regions, and seasons and are largely related to net surface shortwave radiation changes.
Jie Luo, Zhengqiang Li, Chenchong Zhang, Qixing Zhang, Yongming Zhang, Ying Zhang, Gabriele Curci, and Rajan K. Chakrabarty
Atmos. Chem. Phys., 22, 7647–7666, https://doi.org/10.5194/acp-22-7647-2022, https://doi.org/10.5194/acp-22-7647-2022, 2022
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The fractal black carbon was applied to re-evaluate the regional impacts of morphologies on aerosol–radiation interactions (ARIs), and the effects were compared between the US and China. The regional-mean clear-sky ARI is significantly affected by the BC morphology, and relative differences of 17.1 % and 38.7 % between the fractal model with a Df of 1.8 and the spherical model were observed in eastern China and the northwest US, respectively.
Suvarna Fadnavis, Prashant Chavan, Akash Joshi, Sunil M. Sonbawne, Asutosh Acharya, Panuganti C. S. Devara, Alexandru Rap, Felix Ploeger, and Rolf Müller
Atmos. Chem. Phys., 22, 7179–7191, https://doi.org/10.5194/acp-22-7179-2022, https://doi.org/10.5194/acp-22-7179-2022, 2022
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We show that large amounts of anthropogenic aerosols are transported from South Asia to the northern Indian Ocean. These aerosols are then lifted into the UTLS by the ascending branch of the Hadley circulation. They are further transported to the Southern Hemisphere and downward via westerly ducts over the tropical Atlantic and Pacific. These aerosols increase tropospheric heating, resulting in an increase in water vapor, which is then transported to the UTLS.
Xiadong An, Wen Chen, Peng Hu, Shangfeng Chen, and Lifang Sheng
Atmos. Chem. Phys., 22, 6507–6521, https://doi.org/10.5194/acp-22-6507-2022, https://doi.org/10.5194/acp-22-6507-2022, 2022
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The intraseasonal NAAA usually establishes quickly on day −3 with a life span of 8 days. Further results revealed that the probability of regional PM2.5 pollution related to the NAAA for at least 2 days in the NCP is 80% in NDJ period 2000–2021. Particularly, air quality in the NCP tends to deteriorate on day 2 prior to the peak day of the NAAA and reaches a peak on day −1 with a life cycle of 4 days. The corresponding meteorological conditions support these conclusions.
Jianbing Jin, Mijie Pang, Arjo Segers, Wei Han, Li Fang, Baojie Li, Haochuan Feng, Hai Xiang Lin, and Hong Liao
Atmos. Chem. Phys., 22, 6393–6410, https://doi.org/10.5194/acp-22-6393-2022, https://doi.org/10.5194/acp-22-6393-2022, 2022
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Super dust storms reappeared in East Asia last spring after being absent for one and a half decades. Accurate simulation of such super sandstorms is valuable, but challenging due to imperfect emissions. In this study, the emissions of these dust storms are estimated by assimilating multiple observations. The results reveal that emissions originated from both China and Mongolia. However, for northern China, long-distance transport from Mongolia contributes much more dust than Chinese deserts.
Thanh Le and Deg-Hyo Bae
Atmos. Chem. Phys., 22, 5253–5263, https://doi.org/10.5194/acp-22-5253-2022, https://doi.org/10.5194/acp-22-5253-2022, 2022
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Here we assess the response of dust activities to El Niño–Southern Oscillation (ENSO) over the 1850–2014 period using climate model outputs. Our results show that ENSO is an important driver of dust deposition and dust transportation with high consensus across models. However, the results indicate that ENSO is unlikely to show causal impacts on dust emissions of major dust sources. This study allows us to obtain further understanding of the linkages between ENSO and dust cycle at a global scale.
Yun Lin, Yuan Wang, Bowen Pan, Jiaxi Hu, Song Guo, Misti Levy Zamora, Pengfei Tian, Qiong Su, Yuemeng Ji, Jiayun Zhao, Mario Gomez-Hernandez, Min Hu, and Renyi Zhang
Atmos. Chem. Phys., 22, 4951–4967, https://doi.org/10.5194/acp-22-4951-2022, https://doi.org/10.5194/acp-22-4951-2022, 2022
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Severe regional haze events, which are characterized by exceedingly high levels of fine particulate matter (PM), occur frequently in many developing countries (such as China and India), with profound implications for human health, weather, and climate. Our work establishes a synthetic view for the dominant regional features during severe haze events, unraveling rapid in situ PM production and inefficient transport, both of which are amplified by atmospheric stagnation.
Ranjeet S. Sokhi, Nicolas Moussiopoulos, Alexander Baklanov, John Bartzis, Isabelle Coll, Sandro Finardi, Rainer Friedrich, Camilla Geels, Tiia Grönholm, Tomas Halenka, Matthias Ketzel, Androniki Maragkidou, Volker Matthias, Jana Moldanova, Leonidas Ntziachristos, Klaus Schäfer, Peter Suppan, George Tsegas, Greg Carmichael, Vicente Franco, Steve Hanna, Jukka-Pekka Jalkanen, Guus J. M. Velders, and Jaakko Kukkonen
Atmos. Chem. Phys., 22, 4615–4703, https://doi.org/10.5194/acp-22-4615-2022, https://doi.org/10.5194/acp-22-4615-2022, 2022
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This review of air quality research focuses on developments over the past decade. The article considers current and future challenges that are important from air quality research and policy perspectives and highlights emerging prominent gaps of knowledge. The review also examines how air pollution management needs to adapt to new challenges and makes recommendations to guide the direction for future air quality research within the wider community and to provide support for policy.
Xin Yin, Cong Jiang, Yaping Shao, Ning Huang, and Jie Zhang
Atmos. Chem. Phys., 22, 4509–4522, https://doi.org/10.5194/acp-22-4509-2022, https://doi.org/10.5194/acp-22-4509-2022, 2022
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Through a series of numerical experiments using the large-eddy-simulation model, we have developed an improved particle deposition scheme that takes into account transient wind shear fluctuations. Statistical analysis of the simulation results shows that the shear stress can be well approximated by a Weibull distribution and that the new scheme provides more accurate predictions than the conventional scheme, particularly under weak wind conditions and strong convective atmospheric conditions.
Cited articles
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Short summary
Fires including peatland burning in Southeast Asia (SA) have become a major concern in the region. In order to improve our understanding of the spatiotemporal coverage and influence of fire aerosols in SA, we have used surface visibility and aerosol observations, added by decade-long simulations using the WRF model with a fire aerosol module. Our result suggests that mitigation policies targeting both biomass burning and fossil fuel burning sources need to be implemented.
Fires including peatland burning in Southeast Asia (SA) have become a major concern in the...
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