Articles | Volume 17, issue 19
https://doi.org/10.5194/acp-17-12133-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-17-12133-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
12 Oct 2017
Research article |
| 12 Oct 2017
Impact of aerosol hygroscopic growth on retrieving aerosol extinction coefficient profiles from elastic-backscatter lidar signals
Gang Zhao
Department of Atmospheric and Oceanic Sciences, School of
Physics, Peking University, Beijing, China
Chunsheng Zhao
CORRESPONDING AUTHOR
Department of Atmospheric and Oceanic Sciences, School of
Physics, Peking University, Beijing, China
Department of Atmospheric and Oceanic Sciences, School of
Physics, Peking University, Beijing, China
Jiangchuan Tao
Department of Atmospheric and Oceanic Sciences, School of
Physics, Peking University, Beijing, China
Wangshu Tan
Department of Atmospheric and Oceanic Sciences, School of
Physics, Peking University, Beijing, China
Yuxuan Bian
State Key Laboratory of Severe Weather, Chinese Academy of
Meteorological Sciences, Beijing, 100081, China
Department of Atmospheric and Oceanic Sciences, School of
Physics, Peking University, Beijing, China
Chengcai Li
Department of Atmospheric and Oceanic Sciences, School of
Physics, Peking University, Beijing, China
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Juan Hong, Min Tang, Qiaoqiao Wang, Nan Ma, Shaowen Zhu, Shaobin Zhang, Xihao Pan, Linhong Xie, Guo Li, Uwe Kuhn, Chao Yan, Jiangchuan Tao, Ye Kuang, Yao He, Wanyun Xu, Runlong Cai, Yaqing Zhou, Zhibin Wang, Guangsheng Zhou, Bin Yuan, Yafang Cheng, and Hang Su
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Atmos. Chem. Phys., 23, 3195–3205, https://doi.org/10.5194/acp-23-3195-2023, https://doi.org/10.5194/acp-23-3195-2023, 2023
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Chemical compositions vary between and within particles due to the complex sources and aging processes, causing particle-to-particle heterogeneity in aerosol hygroscopicity, which is of great importance to aerosol climatic and environmental effects. This study proposes an algorithm to quantify the heterogeneity from in situ measurements, sheds light on the reanalysis of the existing H-TDMA datasets, and could have a large impact on how we use and think about these datasets.
Jiangchuan Tao, Biao Luo, Weiqi Xu, Gang Zhao, Hanbin Xu, Biao Xue, Miaomiao Zhai, Wanyun Xu, Huarong Zhao, Sanxue Ren, Guangsheng Zhou, Li Liu, Ye Kuang, and Yele Sun
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-840, https://doi.org/10.5194/acp-2022-840, 2023
Revised manuscript accepted for ACP
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Using simultaneous measurements of DMA-CCNC, H/VTDMA and DMA-SP2, impacts of primary emissions and secondary aerosol formations on changes of aerosol physicochemical properties were comprehensively investigated. It was found that intercomparisons among aerosol mixing state parameters derived from different techniques can help getting more insights into aerosol physical properties which in turn will aid the investigation of emission characteristics and secondary aerosol formation pathways.
Weilun Zhao, Gang Zhao, Ying Li, Song Guo, Nan Ma, Lizi Tang, Zirui Zhang, and Chunsheng Zhao
Atmos. Meas. Tech., 15, 6807–6817, https://doi.org/10.5194/amt-15-6807-2022, https://doi.org/10.5194/amt-15-6807-2022, 2022
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A new method to determine black carbon mass size distribution (BCMSD) was proposed using the size-resolved absorption coefficient measured by an aerodynamic aerosol classifier in tandem with an aethalometer. This new method fills the gap in the high-time-resolution measurement of BCMSD ranging from upper submicron particle sizes to larger than 1 µm. This method can be applied to field measurement of BCMSD extensively for better understanding BC aging and better estimating the BC climate effect.
Biao Luo, Ye Kuang, Shan Huang, Qicong Song, Weiwei Hu, Wei Li, Yuwen Peng, Duohong Chen, Dingli Yue, Bin Yuan, and Min Shao
Atmos. Chem. Phys., 22, 12401–12415, https://doi.org/10.5194/acp-22-12401-2022, https://doi.org/10.5194/acp-22-12401-2022, 2022
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We performed comprehensive analysis on biomass burning organic aerosol (BBOA) size distributions, as well as mass scattering and absorption efficiencies, with an improved method of on-line quantification of brown carbon absorptions. Both BBOA volume size distribution and retrieved refractive index depend highly on combustion conditions represented by the black carbon content, which has significant implications for BBOA climate effect simulations.
Gang Zhao, Tianyi Tan, Shuya Hu, Zhuofei Du, Dongjie Shang, Zhijun Wu, Song Guo, Jing Zheng, Wenfei Zhu, Mengren Li, Limin Zeng, and Min Hu
Atmos. Chem. Phys., 22, 10861–10873, https://doi.org/10.5194/acp-22-10861-2022, https://doi.org/10.5194/acp-22-10861-2022, 2022
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Black carbon is the second strongest absorbing component in the atmosphere that exerts warming effects on climate. One critical challenge in quantifying the ambient black carbon's radiative effects is addressing the BC microphysical properties. In this study, the microphysical properties of the aged and fresh BC particles are synthetically analyzed under different atmospheres. The measurement results can be further used in models to help constrain the uncertainties of the BC radiative effects.
Li Liu, Ye Kuang, Miaomiao Zhai, Biao Xue, Yao He, Jun Tao, Biao Luo, Wanyun Xu, Jiangchuan Tao, Changqin Yin, Fei Li, Hanbing Xu, Tao Deng, Xuejiao Deng, Haobo Tan, and Min Shao
Atmos. Chem. Phys., 22, 7713–7726, https://doi.org/10.5194/acp-22-7713-2022, https://doi.org/10.5194/acp-22-7713-2022, 2022
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Using simultaneous measurements of a humidified nephelometer system and an aerosol chemical speciation monitor in winter in Guangzhou, the strongest scattering ability of more oxidized oxygenated organic aerosol (MOOA) among aerosol components considering their dry-state scattering ability and water uptake ability was revealed, leading to large impacts of MOOA on visibility degradation. This has important implications for visibility improvement in China and aerosol radiative effect simulation.
Zhongjing Jiang and Jing Li
Atmos. Chem. Phys., 22, 7273–7285, https://doi.org/10.5194/acp-22-7273-2022, https://doi.org/10.5194/acp-22-7273-2022, 2022
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This study investigates the changes of tropospheric ozone in China associated with EP and CP El Niño, using satellite observations and the GEOS-Chem model. We found that El Niño generally leads to lower tropospheric ozone (LTO) decrease over most parts of China; La Niña acts the opposite. The difference between LTO changes during EP and CP El Niño primarily lies in southern China. Regional transport and chemical processes play the leading and secondary roles in driving the LTO changes.
Jingnan Shi, Juan Hong, Nan Ma, Qingwei Luo, Yao He, Hanbing Xu, Haobo Tan, Qiaoqiao Wang, Jiangchuan Tao, Yaqing Zhou, Shuang Han, Long Peng, Linhong Xie, Guangsheng Zhou, Wanyun Xu, Yele Sun, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 22, 4599–4613, https://doi.org/10.5194/acp-22-4599-2022, https://doi.org/10.5194/acp-22-4599-2022, 2022
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In this study, we investigated the hygroscopicity of submicron aerosols at a rural site in the North China Plain during the winter of 2018, using a HTDMA and a CV-ToF-ACSM. We observed differences in aerosol hygroscopicity during two distinct episodes with different primary emissions and secondary aerosol formation processes. These results provide an improved understanding of the complex influence of sources and aerosol evolution processes on their hygroscopicity.
Shuang Han, Juan Hong, Qingwei Luo, Hanbing Xu, Haobo Tan, Qiaoqiao Wang, Jiangchuan Tao, Yaqing Zhou, Long Peng, Yao He, Jingnan Shi, Nan Ma, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 22, 3985–4004, https://doi.org/10.5194/acp-22-3985-2022, https://doi.org/10.5194/acp-22-3985-2022, 2022
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We present the hygroscopicity of 23 organic species with different physicochemical properties using a hygroscopicity tandem differential mobility analyzer (HTDMA) and compare the results with previous studies. Based on the hygroscopicity parameter κ, the influence of different physicochemical properties that potentially drive hygroscopicity, such as the functionality, water solubility, molar volume, and O : C ratio of organics, are examined separately.
Xiajie Yang, Qiaoqiao Wang, Nan Ma, Weiwei Hu, Yang Gao, Zhijiong Huang, Junyu Zheng, Bin Yuan, Ning Yang, Jiangchuan Tao, Juan Hong, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 22, 3743–3762, https://doi.org/10.5194/acp-22-3743-2022, https://doi.org/10.5194/acp-22-3743-2022, 2022
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We use the GEOS-Chem model with additional anthropogenic and biomass burning chlorine emissions combined with updated parameterizations for N2O5 ＋ Cl chemistry to investigate the impacts of chlorine chemistry on air quality in China. Our study not only significantly improves the model's performance but also demonstrates the importance of non-sea-salt chlorine sources as well as an appropriate parameterization for N2O5 ＋ Cl chemistry to the impact of chlorine chemistry in China.
Yaqing Zhou, Nan Ma, Qiaoqiao Wang, Zhibin Wang, Chunrong Chen, Jiangchuan Tao, Juan Hong, Long Peng, Yao He, Linhong Xie, Shaowen Zhu, Yuxuan Zhang, Guo Li, Wanyun Xu, Peng Cheng, Uwe Kuhn, Guangsheng Zhou, Pingqing Fu, Qiang Zhang, Hang Su, and Yafang Cheng
Atmos. Chem. Phys., 22, 2029–2047, https://doi.org/10.5194/acp-22-2029-2022, https://doi.org/10.5194/acp-22-2029-2022, 2022
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This study characterizes size-resolved particle effective densities and their evolution associated with emissions and aging processes in a rural area of the North China Plain. Particle effective density exhibits a high-frequency bimodal distribution, and two density modes exhibit opposite trends with increasing particle size. SIA and BC mass fractions are key factors of particle effective density, and a value of 0.6 g cm−3 is appropriate to represent BC effective density in bulk particles.
Gang Zhao, Tianyi Tan, Yishu Zhu, Min Hu, and Chunsheng Zhao
Atmos. Chem. Phys., 21, 18055–18063, https://doi.org/10.5194/acp-21-18055-2021, https://doi.org/10.5194/acp-21-18055-2021, 2021
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In this study, the black carbon (BC) mixing state index (χ) is developed to quantify the dispersion of ambient black carbon aerosol mixing states based on binary systems of BC and other non-black carbon components. We demonstrate that the BC light absorption enhancement increases with χ for the same MR, which indicates that χ can be employed as a factor to constrain the light absorption enhancement of ambient BC.
Siying Chen, Rongzheng Cao, Yixuan Xie, Yinchao Zhang, Wangshu Tan, He Chen, Pan Guo, and Peitao Zhao
Atmos. Chem. Phys., 21, 11489–11504, https://doi.org/10.5194/acp-21-11489-2021, https://doi.org/10.5194/acp-21-11489-2021, 2021
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In this study, the seasonal variation in Aeolus wind product performance over China is analyzed by using L-band radiosonde detection data and ERA5 reanalysis data. The results show that the Aeolus wind product performance is affected by seasonal factors, which may be caused by seasonal changes in wind direction and cloud distribution.
Liangying Zeng, Yang Yang, Hailong Wang, Jing Wang, Jing Li, Lili Ren, Huimin Li, Yang Zhou, Pinya Wang, and Hong Liao
Atmos. Chem. Phys., 21, 10745–10761, https://doi.org/10.5194/acp-21-10745-2021, https://doi.org/10.5194/acp-21-10745-2021, 2021
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Using an aerosol–climate model, the impacts of El Niño with different durations on aerosols in China are examined. The modulation on aerosol concentrations and haze days by short-duration El Niño events is 2–3 times more than that by long-duration El Niño events in China. The frequency of short-duration El Niño has been increasing significantly in recent decades, suggesting that El Niño events have exerted increasingly intense modulation on aerosol pollution in China over the past few decades.
Jie Qiu, Wangshu Tan, Gang Zhao, Yingli Yu, and Chunsheng Zhao
Atmos. Meas. Tech., 14, 4879–4891, https://doi.org/10.5194/amt-14-4879-2021, https://doi.org/10.5194/amt-14-4879-2021, 2021
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Considering nephelometers' major problems of a nonideal Lambertian light source and angle truncation, a new correction method based on a machine learning model is proposed. Our method has the advantage of obtaining data with high accuracy while achieving self-correction, which means that researchers can get more accurate scattering coefficients without the need for additional observation data. This method provides a more precise estimation of the aerosol’s direct radiative forcing.
Ye Kuang, Shan Huang, Biao Xue, Biao Luo, Qicong Song, Wei Chen, Weiwei Hu, Wei Li, Pusheng Zhao, Mingfu Cai, Yuwen Peng, Jipeng Qi, Tiange Li, Sihang Wang, Duohong Chen, Dingli Yue, Bin Yuan, and Min Shao
Atmos. Chem. Phys., 21, 10375–10391, https://doi.org/10.5194/acp-21-10375-2021, https://doi.org/10.5194/acp-21-10375-2021, 2021
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We found that organic aerosol factors with identified sources perform much better than oxidation level parameters in characterizing variations in organic aerosol hygroscopicity, and secondary aerosol formations associated with different sources have distinct effects on organic aerosol hygroscopicity. It reveals that source-oriented organic aerosol hygroscopicity investigations might result in more appropriate parameterization approaches in chemical and climate models.
Gang Zhao, Yishu Zhu, Zhijun Wu, Taomou Zong, Jingchuan Chen, Tianyi Tan, Haichao Wang, Xin Fang, Keding Lu, Chunsheng Zhao, and Min Hu
Atmos. Chem. Phys., 21, 9995–10004, https://doi.org/10.5194/acp-21-9995-2021, https://doi.org/10.5194/acp-21-9995-2021, 2021
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New particle formation is thought to contribute half of the global cloud condensation nuclei. We find that the new particle formation is more likely to happen in the upper boundary layer than that at the ground, which can be partially explained by the aerosol–radiation interaction. Our study emphasizes the influence of aerosol–radiation interaction on the NPF.
Tianyi Tan, Min Hu, Zhuofei Du, Gang Zhao, Dongjie Shang, Jing Zheng, Yanhong Qin, Mengren Li, Yusheng Wu, Limin Zeng, Song Guo, and Zhijun Wu
Atmos. Chem. Phys., 21, 8499–8510, https://doi.org/10.5194/acp-21-8499-2021, https://doi.org/10.5194/acp-21-8499-2021, 2021
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Every year in the pre-monsoon season, the black carbon (BC) aerosols originated from biomass burning in southern Asia are easily transported to the Tibetan Plateau (TP) by the convenience of westerly wind. This study reveals that the BC aerosols in the aged biomass burning plumes strongly enhance the total light absorption over the TP, and the aging process during the long-range transport will further strengthen the radiative heating of those BC aerosols.
Jiangchuan Tao, Ye Kuang, Nan Ma, Juan Hong, Yele Sun, Wanyun Xu, Yanyan Zhang, Yao He, Qingwei Luo, Linhong Xie, Hang Su, and Yafang Cheng
Atmos. Chem. Phys., 21, 7409–7427, https://doi.org/10.5194/acp-21-7409-2021, https://doi.org/10.5194/acp-21-7409-2021, 2021
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The mechanism of secondary aerosol (SA) formation can be affected by relative humidity (RH) and has different influences on the particle CCN activity under different RH conditions. In the North China Plain, we find different responses of CCN activity and enhancements of CCN number concentration to SA formation under different RH conditions. In addition, variations of aerosol mixing state due to SA formation contribute some of the largest uncertainties in predicting CCN number concentration.
Zhongjing Jiang, Jing Li, Xiao Lu, Cheng Gong, Lin Zhang, and Hong Liao
Atmos. Chem. Phys., 21, 2601–2613, https://doi.org/10.5194/acp-21-2601-2021, https://doi.org/10.5194/acp-21-2601-2021, 2021
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This study demonstrates that the intensity of the western Pacific subtropical high (WPSH), a major synoptic pattern in the northern Pacific during summer, can induce a dipole change in surface ozone pollution over eastern China. Ozone concentration increases in the north and decreases in the south during the strong WPSH phase, and vice versa. The change in chemical processes associated with the WPSH change plays a decisive role, whereas the natural emission of ozone precursors accounts for ~ 30 %.
Weilun Zhao, Wangshu Tan, Gang Zhao, Chuanyang Shen, Yingli Yu, and Chunsheng Zhao
Atmos. Meas. Tech., 14, 1319–1331, https://doi.org/10.5194/amt-14-1319-2021, https://doi.org/10.5194/amt-14-1319-2021, 2021
Chuanyang Shen, Gang Zhao, and Chunsheng Zhao
Atmos. Meas. Tech., 14, 1293–1301, https://doi.org/10.5194/amt-14-1293-2021, https://doi.org/10.5194/amt-14-1293-2021, 2021
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Aerosol hygroscopicity measured by the humidified tandem differential mobility analyzer (HTDMA) is affected by multiply charged particles from two aspects: (1) number contribution and (2) the weakening effect. An algorithm is proposed to do the multi-charge correction and applied to a field measurement. Results show that the difference between corrected and measured size-resolved κ can reach 0.05, highlighting that special attention needs to be paid to the multi-charge effect when using HTDMA.
Chuanyang Shen, Gang Zhao, Weilun Zhao, Ping Tian, and Chunsheng Zhao
Atmos. Chem. Phys., 21, 1375–1388, https://doi.org/10.5194/acp-21-1375-2021, https://doi.org/10.5194/acp-21-1375-2021, 2021
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Submicron particles larger than 300 nm dominate the aerosol light extinction and mass concentration in the urban environment. Aerosol hygroscopic properties extended to 600 nm were investigated at an urban site. Our results find that there exists a large fraction of a less hygroscopic group above 300 nm, and the hygroscopicity in this size range is enhanced significantly with the development of pollution levels. The hygroscopicity variation contributes greatly to the low visibility.
Quan Liu, Dantong Liu, Qian Gao, Ping Tian, Fei Wang, Delong Zhao, Kai Bi, Yangzhou Wu, Shuo Ding, Kang Hu, Jiale Zhang, Deping Ding, and Chunsheng Zhao
Atmos. Chem. Phys., 20, 3931–3944, https://doi.org/10.5194/acp-20-3931-2020, https://doi.org/10.5194/acp-20-3931-2020, 2020
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We present a series of aircraft-based in situ measurements of aerosol chemical components and size distributions over the North China Plain, and the hygroscopicity is derived from aerosol chemical composition. These results reveal the vertical characteristics of aerosol hygroscopicity, and we investigated their impacts on optical properties and activation under different moisture and pollution conditions over this polluted region.
Tianning Su, Zhanqing Li, Chengcai Li, Jing Li, Wenchao Han, Chuanyang Shen, Wangshu Tan, Jing Wei, and Jianping Guo
Atmos. Chem. Phys., 20, 3713–3724, https://doi.org/10.5194/acp-20-3713-2020, https://doi.org/10.5194/acp-20-3713-2020, 2020
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We study the role of aerosol vertical distribution in thermodynamic stability and PBL development. Under different aerosol vertical structures, the diurnal cycles of PBLH and PM2.5 show distinct characteristics. Large differences in the heating rate affect atmospheric buoyancy and stability differently under different aerosol structures. As a result, the aerosol–PBL interaction can be strengthened by the inverse aerosol structure and potentially neutralized by the decreasing structure.
Jing Wei, Zhanqing Li, Maureen Cribb, Wei Huang, Wenhao Xue, Lin Sun, Jianping Guo, Yiran Peng, Jing Li, Alexei Lyapustin, Lei Liu, Hao Wu, and Yimeng Song
Atmos. Chem. Phys., 20, 3273–3289, https://doi.org/10.5194/acp-20-3273-2020, https://doi.org/10.5194/acp-20-3273-2020, 2020
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This study introduced an enhanced space–time extremely randomized trees (STET) approach to improve the 1 km resolution ground-level PM2.5 estimates across China using the remote sensing technology. The STET model shows high accuracy and strong predictive power and appears to outperform most models reported by previous studies. Thus, it is of great importance for future air pollution studies at medium- or small-scale areas and will be applied to generate the historical PM2.5 dataset across China.
Ping Tian, Dantong Liu, Delong Zhao, Chenjie Yu, Quan Liu, Mengyu Huang, Zhaoze Deng, Liang Ran, Yunfei Wu, Shuo Ding, Kang Hu, Gang Zhao, Chunsheng Zhao, and Deping Ding
Atmos. Chem. Phys., 20, 2603–2622, https://doi.org/10.5194/acp-20-2603-2020, https://doi.org/10.5194/acp-20-2603-2020, 2020
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This study paints a full picture of the evolution of vertical characteristics of aerosol optical properties and shortwave heating impacts of carbonaceous aerosols during different stages of pollution events over the Beijing region and highlights the increased contribution of brown carbon absorption, especially at higher levels, during pollution.
Yu Wang, Ying Chen, Zhijun Wu, Dongjie Shang, Yuxuan Bian, Zhuofei Du, Sebastian H. Schmitt, Rong Su, Georgios I. Gkatzelis, Patrick Schlag, Thorsten Hohaus, Aristeidis Voliotis, Keding Lu, Limin Zeng, Chunsheng Zhao, M. Rami Alfarra, Gordon McFiggans, Alfred Wiedensohler, Astrid Kiendler-Scharr, Yuanhang Zhang, and Min Hu
Atmos. Chem. Phys., 20, 2161–2175, https://doi.org/10.5194/acp-20-2161-2020, https://doi.org/10.5194/acp-20-2161-2020, 2020
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Severe haze events, with high particulate nitrate (pNO3−) burden, frequently prevail in Beijing. In this study, we demonstrate a mutual-promotion effect between aerosol water uptake and pNO3− formation backed up by theoretical calculations and field observations throughout a typical pNO3−-dominated haze event in Beijing wintertime. This self-amplified mutual-promotion effect between aerosol water content and particulate nitrate can rapidly deteriorate air quality and degrade visibility.
Ye Kuang, Yao He, Wanyun Xu, Pusheng Zhao, Yafang Cheng, Gang Zhao, Jiangchuan Tao, Nan Ma, Hang Su, Yanyan Zhang, Jiayin Sun, Peng Cheng, Wenda Yang, Shaobin Zhang, Cheng Wu, Yele Sun, and Chunsheng Zhao
Atmos. Chem. Phys., 20, 865–880, https://doi.org/10.5194/acp-20-865-2020, https://doi.org/10.5194/acp-20-865-2020, 2020
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A new method was developed to calculate hygroscopicity parameter κ of organic aerosols (κOA) based on aerosol light-scattering measurements and bulk aerosol chemical-composition measurements. Derived high-time-resolution κOA varied in a wide range (near 0 to 0.25), and the organic aerosol oxidation degree significantly impacts variations in κOA. Distinct diurnal variation in κOA is found, and its relationship with oxygenated organic aerosol is discussed.
Gang Zhao, Jiangchuan Tao, Ye Kuang, Chuanyang Shen, Yingli Yu, and Chunsheng Zhao
Atmos. Chem. Phys., 19, 13175–13188, https://doi.org/10.5194/acp-19-13175-2019, https://doi.org/10.5194/acp-19-13175-2019, 2019
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Characteristics of the black carbon size distribution (BCMSD) are studied by using our developed measurement system. Results show that the BCMSDs have two modes and the mean peak diameters are 150 nm and 503 nm, respectively. The coarser mode varies significantly under different pollution conditions, which gives rise to significant variation in aerosol bulk optical properties. Our study reveals that the BCMSD as well as the mixing state in estimating aerosol radiative forcing matters.
Gang Zhao, Tianyi Tan, Weilun Zhao, Song Guo, Ping Tian, and Chunsheng Zhao
Atmos. Chem. Phys., 19, 12875–12885, https://doi.org/10.5194/acp-19-12875-2019, https://doi.org/10.5194/acp-19-12875-2019, 2019
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Traditionally, the real part of the refractive index (RRI) of ambient aerosols is calculated by their chemical components. In this study, we demonstrate that the RRI is highly related to effective density rather than chemical components using field measurements. For the first time, a parameterization scheme for ambient aerosol RRI using effective density is proposed. This simple scheme is more reliable and ready to use in the calculation of aerosol optics and radiation.
Wanyun Xu, Ye Kuang, Chunsheng Zhao, Jiangchuan Tao, Gang Zhao, Yuxuan Bian, Wen Yang, Yingli Yu, Chuanyang Shen, Linlin Liang, Gen Zhang, Weili Lin, and Xiaobin Xu
Atmos. Chem. Phys., 19, 10557–10570, https://doi.org/10.5194/acp-19-10557-2019, https://doi.org/10.5194/acp-19-10557-2019, 2019
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The study of HONO, the primary source of OH radicals, is crucial for atmospheric photochemistry and heterogeneous chemistry. Heterogeneous NO2 conversion was shown to be one of the missing sources of HONO on the North China Plain, but the reaction path is still under debate. In this work, evidence was found that NH3 was the key factor that promoted the hydrolysis of NO2, leading to the explosive growth of HONO and nitrate, suggesting that NH3 emission control measures are urgently needed.
Wangshu Tan, Gang Zhao, Yingli Yu, Chengcai Li, Jian Li, Ling Kang, Tong Zhu, and Chunsheng Zhao
Atmos. Meas. Tech., 12, 3825–3839, https://doi.org/10.5194/amt-12-3825-2019, https://doi.org/10.5194/amt-12-3825-2019, 2019
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A new method to retrieve CCN number concentrations using multiwavelength Raman lidars is proposed. The method implements hygroscopic enhancements of backscatter and extinction with relative humidity to represent particle hygroscopicity. The retrieved CCN number concentrations are in good agreement with theoretical calculated values. Sensitivity tests indicate that retrieval error in CCN arises mostly from uncertainties in extinction coefficients and RH profiles.
Gang Zhao, Weilun Zhao, and Chunsheng Zhao
Atmos. Meas. Tech., 12, 3541–3550, https://doi.org/10.5194/amt-12-3541-2019, https://doi.org/10.5194/amt-12-3541-2019, 2019
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A new method is proposed to retrieve the size-resolved real part of the refractive index (RRI). The main principle of deriving the RRI is measuring the scattering intensity by a single-particle soot photometer of a size-selected aerosol. This method is validated by a series of calibration experiments using the components of the known RI. The retrieved size-resolved RRI covers a wide range, from 200 nm to 450 nm, with uncertainty of less than 0.02.
Yingjie Zhang, Wei Du, Yuying Wang, Qingqing Wang, Haofei Wang, Haitao Zheng, Fang Zhang, Hongrong Shi, Yuxuan Bian, Yongxiang Han, Pingqing Fu, Francesco Canonaco, André S. H. Prévôt, Tong Zhu, Pucai Wang, Zhanqing Li, and Yele Sun
Atmos. Chem. Phys., 18, 14637–14651, https://doi.org/10.5194/acp-18-14637-2018, https://doi.org/10.5194/acp-18-14637-2018, 2018
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We have a comprehensive characterization of aerosol chemistry and particle growth events at a downwind site of a highly polluted city in the North China Plain. Aerosol particles at the urban downwind site were highly aged and mainly from secondary formation. New particle growth events were also frequently observed on both clean and polluted days. While both sulfate and SOA played important roles in particle growth during clean periods, SOA was more important than sulfate during polluted events.
Gang Zhao, Chunsheng Zhao, Ye Kuang, Yuxuan Bian, Jiangchuan Tao, Chuanyang Shen, and Yingli Yu
Atmos. Chem. Phys., 18, 9049–9060, https://doi.org/10.5194/acp-18-9049-2018, https://doi.org/10.5194/acp-18-9049-2018, 2018
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The aerosol asymmetry factor (g) is one of the most important factors for assessing direct aerosol radiative forcing (DARF) and remote sensing. So far, few studies have focused on the measurements and parameterization of g. Our study shows that relative humidity has significant impacts on g and DARF due to aerosol hygroscopic growth. For the first time, a novel method based on measurements from the humidified nephelometer system is proposed to calculate g accurately with high time resolution.
Ye Kuang, Chun Sheng Zhao, Gang Zhao, Jiang Chuan Tao, Wanyun Xu, Nan Ma, and Yu Xuan Bian
Atmos. Meas. Tech., 11, 2967–2982, https://doi.org/10.5194/amt-11-2967-2018, https://doi.org/10.5194/amt-11-2967-2018, 2018
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Aerosol water has become an important topic recently because of its implications for multiphase secondary aerosol formation during severe haze events in Asia. This is a timely paper on this topic; a novel method is proposed to calculate ambient aerosol liquid water contents based only on measurements of a three-wavelength humidified nephelometer system. The advantage of this method is that this technique can provide continuous measurements of the changing ambient conditions.
Jing Li, Chengcai Li, and Chunsheng Zhao
Atmos. Chem. Phys., 18, 3289–3298, https://doi.org/10.5194/acp-18-3289-2018, https://doi.org/10.5194/acp-18-3289-2018, 2018
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Our study investigates the long-term trends of extreme aerosol pollution in China over the past ~ 30 years. In the 1980s, an overall positive trend is found throughout China with the extreme trend exceeding the mean trend, except for Northwest China and the North China Plain. In the 1990s, the extreme trends continued to dominate in the south while they yield to the mean trend in the north. After 2000, the extreme trend became weaker than the mean trend overall.
Jiangchuan Tao, Chunsheng Zhao, Ye Kuang, Gang Zhao, Chuanyang Shen, Yingli Yu, Yuxuan Bian, and Wanyun Xu
Atmos. Meas. Tech., 11, 895–906, https://doi.org/10.5194/amt-11-895-2018, https://doi.org/10.5194/amt-11-895-2018, 2018
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Existing chamber technologies for direct measurements of number concentration of cloud condensation nuclei (NCCN) are sophisticated and expensive. In this paper, a new method is proposed to calculate NCCN based only on measurements of a humidified nephelometer system which have accounted for influences of both aerosol size and aerosol hygroscopicity on NCCN calculation. This new method makes NCCN measurements more convenient and is capable of obtaining NCCN at lower supersaturations.
Yuxuan Bian, Chunsheng Zhao, Wanyun Xu, Gang Zhao, Jiangchuan Tao, and Ye Kuang
Atmos. Meas. Tech., 10, 2313–2322, https://doi.org/10.5194/amt-10-2313-2017, https://doi.org/10.5194/amt-10-2313-2017, 2017
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Aerosol phase function is crucial for understanding the climate effects of aerosols. So far, there is a lack of instruments for measuring the aerosol phase function directly and accurately in laboratory studies and in situ measurements. A novel portable instrument with high angular range and resolution named
charge-coupled device-laser aerosol detective system(CCD-LADS) has been developed and validated for the measurement of the phase function of ambient aerosols in this study.
Ye Kuang, Chunsheng Zhao, Jiangchuan Tao, Yuxuan Bian, Nan Ma, and Gang Zhao
Atmos. Chem. Phys., 17, 6651–6662, https://doi.org/10.5194/acp-17-6651-2017, https://doi.org/10.5194/acp-17-6651-2017, 2017
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A novel approach is proposed in this research to derive the aerosol hygroscopicity parameter based only on measurements from a humidified nephelometer system without any additional information about particle number size distribution and black carbon. New findings in this research can bridge the gap between κ-Köhler theory and the aerosol light-scattering enhancement factor and will make the humidified nephelometer system more convenient when it comes to aerosol hygroscopicity research.
Nan Ma, Chunsheng Zhao, Jiangchuan Tao, Zhijun Wu, Simonas Kecorius, Zhibin Wang, Johannes Größ, Hongjian Liu, Yuxuan Bian, Ye Kuang, Monique Teich, Gerald Spindler, Konrad Müller, Dominik van Pinxteren, Hartmut Herrmann, Min Hu, and Alfred Wiedensohler
Atmos. Chem. Phys., 16, 8593–8607, https://doi.org/10.5194/acp-16-8593-2016, https://doi.org/10.5194/acp-16-8593-2016, 2016
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New particle formation (NPF) is one of main sources of cloud condensation nuclei (CCN) in the atmosphere. Based on in situ measurements, we found that CCN activity of newly formed particles largely differs in different NPF events. It is therefore difficult to find a simple parameterization of CCN activity for NPF events. Using a fixed size-resolved activation ratio curve or critical diameter is very likely to result in large biases up to 50 % in the calculated NCCN during NPF events.
Y. Kuang, C. S. Zhao, J. C. Tao, and N. Ma
Atmos. Chem. Phys., 15, 5761–5772, https://doi.org/10.5194/acp-15-5761-2015, https://doi.org/10.5194/acp-15-5761-2015, 2015
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In this paper, it is found that the diurnal variations of single scattering albedo (SSA) and asymmetry factor (g) for ambient aerosol are both evident and far different from those of dry state aerosol in the North China Plain (NCP. The diurnal changes of SSA and g have significant impacts on the estimation of daily average direct aerosol radiative effect (DARE) at the top of the atmosphere. In addition, several suggestions are proposed to improve the accurate prediction of DARE in the NCP.
J. Huang, H. Liu, J. H. Crawford, C. Chan, D. B. Considine, Y. Zhang, X. Zheng, C. Zhao, V. Thouret, S. J. Oltmans, S. C. Liu, D. B. A. Jones, S. D. Steenrod, and M. R. Damon
Atmos. Chem. Phys., 15, 5161–5179, https://doi.org/10.5194/acp-15-5161-2015, https://doi.org/10.5194/acp-15-5161-2015, 2015
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High ozone concentrations (up to 94.7ppbv) were frequently observed at an altitude of ~1.5--2km over Beijing during April--May 2005. Ozone due to Asian anthropogenic pollution made major contributions to the observed ozone enhancements. These enhancements typically occurred under southerly wind and warmer conditions. An earlier onset of the Asian summer monsoon would cause more ozone enhancement events in the lower troposphere over the North China Plain in late spring and early summer.
J. Li, B. E. Carlson, O. Dubovik, and A. A. Lacis
Atmos. Chem. Phys., 14, 12271–12289, https://doi.org/10.5194/acp-14-12271-2014, https://doi.org/10.5194/acp-14-12271-2014, 2014
J. C. Tao, C. S. Zhao, N. Ma, and P. F. Liu
Atmos. Chem. Phys., 14, 12055–12067, https://doi.org/10.5194/acp-14-12055-2014, https://doi.org/10.5194/acp-14-12055-2014, 2014
G. Q. Fu, W. Y. Xu, R. F. Yang, J. B. Li, and C. S. Zhao
Atmos. Chem. Phys., 14, 11949–11958, https://doi.org/10.5194/acp-14-11949-2014, https://doi.org/10.5194/acp-14-11949-2014, 2014
Q. S. He, C. C. Li, J. Z. Ma, H. Q. Wang, X. L. Yan, J. Lu, Z. R. Liang, and G. M. Qi
Atmos. Chem. Phys., 14, 11687–11696, https://doi.org/10.5194/acp-14-11687-2014, https://doi.org/10.5194/acp-14-11687-2014, 2014
J. Li, B. E. Carlson, and A. A. Lacis
Atmos. Meas. Tech., 7, 2531–2549, https://doi.org/10.5194/amt-7-2531-2014, https://doi.org/10.5194/amt-7-2531-2014, 2014
J. Chen, C. S. Zhao, N. Ma, and P. Yan
Atmos. Chem. Phys., 14, 8105–8118, https://doi.org/10.5194/acp-14-8105-2014, https://doi.org/10.5194/acp-14-8105-2014, 2014
W. Y. Xu, C. S. Zhao, L. Ran, W. L. Lin, P. Yan, and X. B. Xu
Atmos. Chem. Phys., 14, 7757–7768, https://doi.org/10.5194/acp-14-7757-2014, https://doi.org/10.5194/acp-14-7757-2014, 2014
Y. X. Bian, C. S. Zhao, N. Ma, J. Chen, and W. Y. Xu
Atmos. Chem. Phys., 14, 6417–6426, https://doi.org/10.5194/acp-14-6417-2014, https://doi.org/10.5194/acp-14-6417-2014, 2014
N. Ma, W. Birmili, T. Müller, T. Tuch, Y. F. Cheng, W. Y. Xu, C. S. Zhao, and A. Wiedensohler
Atmos. Chem. Phys., 14, 6241–6259, https://doi.org/10.5194/acp-14-6241-2014, https://doi.org/10.5194/acp-14-6241-2014, 2014
H. J. Liu, C. S. Zhao, B. Nekat, N. Ma, A. Wiedensohler, D. van Pinxteren, G. Spindler, K. Müller, and H. Herrmann
Atmos. Chem. Phys., 14, 2525–2539, https://doi.org/10.5194/acp-14-2525-2014, https://doi.org/10.5194/acp-14-2525-2014, 2014
Z. Z. Deng, C. S. Zhao, N. Ma, L. Ran, G. Q. Zhou, D. R. Lu, and X. J. Zhou
Atmos. Chem. Phys., 13, 6227–6237, https://doi.org/10.5194/acp-13-6227-2013, https://doi.org/10.5194/acp-13-6227-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Remote Sensing | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
The emission, transport, and impacts of the extreme Saharan dust storm of 2015
California wildfire smoke contributes to a positive atmospheric temperature anomaly over the western United States
Light-absorbing black carbon and brown carbon components of smoke aerosol from DSCOVR EPIC measurements over North America and Central Africa
Dust storms from the Taklamakan Desert significantly darken snow surface on surrounding mountains
Opposite effects of aerosols and meteorological parameters on warm clouds in two contrasting regions over eastern China
Effect of wind speed on marine aerosol optical properties over remote oceans with use of spaceborne lidar observations
Assessment of smoke plume height products derived from multisource satellite observations using lidar-derived height metrics for wildfires in the western US
A remote sensing algorithm for vertically resolved cloud condensation nuclei number concentrations from airborne and spaceborne lidar observations
Opinion: Aerosol remote sensing over the next 20 years
Monitoring biomass burning aerosol transport using CALIOP observations and reanalysis models: a Canadian wildfire event in 2019
Thermal infrared observations of a western United States biomass burning aerosol plume
A new look into the impacts of dust radiative effects on the energetics of tropical easterly waves
Wind-driven emissions of coarse-mode particles in an urban environment
Measurement report: Dust and anthropogenic aerosols' vertical distributions over northern China dense aerosols gathered at the top of the mixing layer
Climatological assessment of the vertically resolved optical and microphysical aerosol properties by lidar measurements, sun photometer, and in situ observations over 17 years at Universitat Politècnica de Catalunya (UPC) Barcelona
Aerosol optical depth climatology from the high-resolution MAIAC product over Europe: differences between major European cities and their surrounding environments
Impact of assimilating NOAA VIIRS aerosol optical depth (AOD) observations on global AOD analysis from the Copernicus Atmosphere Monitoring Service (CAMS)
Influence of covariance of aerosol and meteorology on co-located precipitating and non-precipitating clouds over Indo-Gangetic Plains
Spectral dependence of birch and pine pollen optical properties using a synergy of lidar instruments
Validation activities of Aeolus wind products on the southeastern Iberian Peninsula
Thermal infrared dust optical depth and coarse-mode effective diameter over oceans retrieved from collocated MODIS and CALIOP observations
A comprehensive reappraisal of long-term aerosol characteristics, trends, and variability in Asia
Satellite (GOSAT-2 CAI-2) retrieval and surface (ARFINET) observations of aerosol black carbon over India
Spatiotemporal variation characteristics of global fires and their emissions
The (mis)identification of high-latitude dust events using remote sensing methods in the Yukon, Canada: a sub-daily variability analysis
Comparison of dust optical depth from multi-sensor products and MONARCH (Multiscale Online Non-hydrostatic AtmospheRe CHemistry) dust reanalysis over North Africa, the Middle East, and Europe
Understanding day–night differences in dust aerosols over the dust belt of North Africa, the Middle East, and Asia
Satellite observations of smoke–cloud–radiation interactions over the Amazon rainforest
Single-scattering properties of ellipsoidal dust aerosols constrained by measured dust shape distributions
Validation of the TROPOMI/S5P aerosol layer height using EARLINET lidars
Vertical characterization of fine and coarse dust particles during an intense Saharan dust outbreak over the Iberian Peninsula in springtime 2021
Aerosol optical depth regime over megacities of the world
South American 2020 regional smoke plume: intercomparison with previous years, impact on solar radiation, and the role of Pantanal biomass burning season
Circular polarization in atmospheric aerosols
Spatiotemporal continuous estimates of daily 1 km PM2.5 from 2000 to present under the Tracking Air Pollution in China (TAP) framework
Robust evidence for reversal of the trend in aerosol effective climate forcing
Simultaneous retrievals of biomass burning aerosols and trace gases from the ultraviolet to near-infrared over northern Thailand during the 2019 pre-monsoon season
A decadal assessment of the climatology of aerosol and cloud properties over South Africa
Aerosol characterisation in the subtropical eastern North Atlantic region using long-term AERONET measurements
Long-range transport of Asian dust to the Arctic: identification of transport pathways, evolution of aerosol optical properties, and impact assessment on surface albedo changes
Canadian and Alaskan wildfire smoke particle properties, their evolution, and controlling factors, from satellite observations
Evaluation of aerosol optical depths and clear-sky radiative fluxes of the CERES Edition 4.1 SYN1deg data product
Arctic spring and summertime aerosol optical depth baseline from long-term observations and model reanalyses – Part 1: Climatology and trend
Vertical structure of biomass burning aerosol transported over the southeast Atlantic Ocean
Arctic spring and summertime aerosol optical depth baseline from long-term observations and model reanalyses – Part 2: Statistics of extreme AOD events, and implications for the impact of regional biomass burning processes
Aerosol atmospheric rivers: climatology, event characteristics, and detection algorithm sensitivities
Dust transport and advection measurement with spaceborne lidars ALADIN and CALIOP and model reanalysis data
Record-breaking dust loading during two mega dust storm events over northern China in March 2021: aerosol optical and radiative properties and meteorological drivers
Wintertime Saharan dust transport towards the Caribbean: an airborne lidar case study during EUREC4A
Evaluation of aerosol number concentrations from CALIPSO with ATom airborne in situ measurements
Brian Harr, Bing Pu, and Qinjian Jin
Atmos. Chem. Phys., 24, 8625–8651, https://doi.org/10.5194/acp-24-8625-2024, https://doi.org/10.5194/acp-24-8625-2024, 2024
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We found that the formation of the extreme trans-Atlantic African dust event in June 2015 was associated with a brief surge in dust emissions over western North Africa and extreme circulation patterns, including intensified easterly jets, which facilitated the westward transport of dust. The dust plume modified radiative flux along its transport pathway but had minor impacts on air quality in the US due to the record-high Caribbean low-level jet advecting part of the plume to the Pacific.
James L. Gomez, Robert J. Allen, and King-Fai Li
Atmos. Chem. Phys., 24, 6937–6963, https://doi.org/10.5194/acp-24-6937-2024, https://doi.org/10.5194/acp-24-6937-2024, 2024
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Wildfires in California (CA) have grown very large during the past 20 years. These fires emit sunlight-absorbing aerosols. Analyzing observational data, our study finds that aerosols emitted from large fires in northern CA spread throughout CA and Nevada and heat the atmosphere. This heating is consistent with larger-than-normal temperatures and dry conditions. Further study is needed to determine how much the aerosols heat the atmosphere and whether they are drying the atmosphere as well.
Myungje Choi, Alexei Lyapustin, Gregory L. Schuster, Sujung Go, Yujie Wang, Sergey Korkin, Ralph Kahn, Jeffrey S. Reid, Edward J. Hyer, Thomas F. Eck, Mian Chin, David J. Diner, Olga Kalashnikova, Oleg Dubovik, Jhoon Kim, and Hans Moosmüller
EGUsphere, https://doi.org/10.5194/egusphere-2024-1327, https://doi.org/10.5194/egusphere-2024-1327, 2024
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This paper introduces a retrieval algorithm to estimate two key absorbing components in smoke, black carbon and brown carbon, using DSCOVR EPIC measurements. Our analysis reveals distinct smoke properties, including spectral absorption, layer height, and black carbon and brown carbon, over North America and Central Africa. The retrieved smoke properties offer valuable observational constraints for modeling radiative forcing and informing health-related studies.
Yuxuan Xing, Yang Chen, Shirui Yan, Xiaoyi Cao, Yong Zhou, Xueying Zhang, Tenglong Shi, Xiaoying Niu, Dongyou Wu, Jiecan Cui, Yue Zhou, Xin Wang, and Wei Pu
Atmos. Chem. Phys., 24, 5199–5219, https://doi.org/10.5194/acp-24-5199-2024, https://doi.org/10.5194/acp-24-5199-2024, 2024
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This study investigated the impact of dust storms from the Taklamakan Desert on surrounding high mountains and regional radiation balance. Using satellite data and simulations, researchers found that dust storms significantly darken the snow surface in the Tien Shan, Kunlun, and Qilian mountains, reaching mountains up to 1000 km away. This darkening occurs not only in spring but also during summer and autumn, leading to increased absorption of solar radiation.
Yuqin Liu, Tao Lin, Jiahua Zhang, Fu Wang, Yiyi Huang, Xian Wu, Hong Ye, Guoqin Zhang, Xin Cao, and Gerrit de Leeuw
Atmos. Chem. Phys., 24, 4651–4673, https://doi.org/10.5194/acp-24-4651-2024, https://doi.org/10.5194/acp-24-4651-2024, 2024
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A new method, the geographical detector method (GDM), has been applied to satellite data, in addition to commonly used statistical methods, to study the sensitivity of cloud properties to aerosol over China. Different constraints for aerosol and cloud liquid water path apply over polluted and clean areas. The GDM shows that cloud parameters are more sensitive to combinations of parameters than to individual parameters, but confounding effects due to co-variation of parameters cannot be excluded.
Kangwen Sun, Guangyao Dai, Songhua Wu, Oliver Reitebuch, Holger Baars, Jiqiao Liu, and Suping Zhang
Atmos. Chem. Phys., 24, 4389–4409, https://doi.org/10.5194/acp-24-4389-2024, https://doi.org/10.5194/acp-24-4389-2024, 2024
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This paper investigates the correlation between marine aerosol optical properties and wind speeds over remote oceans using the spaceborne lidars ALADIN and CALIOP. Three remote ocean areas are selected. Pure marine aerosol optical properties at 355 nm are derived from ALADIN. The relationships between marine aerosol optical properties and wind speeds are analyzed within and above the marine atmospheric boundary layer, revealing the effect of wind speed on marine aerosols over remote oceans.
Jingting Huang, S. Marcela Loría-Salazar, Min Deng, Jaehwa Lee, and Heather A. Holmes
Atmos. Chem. Phys., 24, 3673–3698, https://doi.org/10.5194/acp-24-3673-2024, https://doi.org/10.5194/acp-24-3673-2024, 2024
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Increased wildfire intensity has resulted in taller wildfire smoke plumes. We investigate the vertical structure of wildfire smoke plumes using aircraft lidar data and establish two effective smoke plume height metrics. Four novel satellite-based plume height products are evaluated for wildfires in the western US. Our results provide guidance on the strengths and limitations of these satellite products and set the stage for improved plume rise estimates by leveraging satellite products.
Piyushkumar N. Patel, Jonathan H. Jiang, Ritesh Gautam, Harish Gadhavi, Olga Kalashnikova, Michael J. Garay, Lan Gao, Feng Xu, and Ali Omar
Atmos. Chem. Phys., 24, 2861–2883, https://doi.org/10.5194/acp-24-2861-2024, https://doi.org/10.5194/acp-24-2861-2024, 2024
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Global measurements of cloud condensation nuclei (CCN) are essential for understanding aerosol–cloud interactions and predicting climate change. To address this gap, we introduced a remote sensing algorithm that retrieves vertically resolved CCN number concentrations from airborne and spaceborne lidar systems. This innovation offers a global distribution of CCN concentrations from space, facilitating model evaluation and precise quantification of aerosol climate forcing.
Lorraine A. Remer, Robert C. Levy, and J. Vanderlei Martins
Atmos. Chem. Phys., 24, 2113–2127, https://doi.org/10.5194/acp-24-2113-2024, https://doi.org/10.5194/acp-24-2113-2024, 2024
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Aerosols are small liquid or solid particles suspended in the atmosphere, including smoke, particulate pollution, dust, and sea salt. Today, we rely on satellites viewing Earth's atmosphere to learn about these particles. Here, we speculate on the future to imagine how satellite viewing of aerosols will change. We expect more public and private satellites with greater capabilities, better ways to infer information from satellites, and merging of data with models.
Xiaoxia Shang, Antti Lipponen, Maria Filioglou, Anu-Maija Sundström, Mark Parrington, Virginie Buchard, Anton S. Darmenov, Ellsworth J. Welton, Eleni Marinou, Vassilis Amiridis, Michael Sicard, Alejandro Rodríguez-Gómez, Mika Komppula, and Tero Mielonen
Atmos. Chem. Phys., 24, 1329–1344, https://doi.org/10.5194/acp-24-1329-2024, https://doi.org/10.5194/acp-24-1329-2024, 2024
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In June 2019, smoke particles from a Canadian wildfire event were transported to Europe. The long-range-transported smoke plumes were monitored with a spaceborne lidar and reanalysis models. Based on the aerosol mass concentrations estimated from the observations, the reanalysis models had difficulties in reproducing the amount and location of the smoke aerosols during the transport event. Consequently, more spaceborne lidar missions are needed for reliable monitoring of aerosol plumes.
Blake T. Sorenson, Jeffrey S. Reid, Jianglong Zhang, Robert E. Holz, William L. Smith Sr., and Amanda Gumber
Atmos. Chem. Phys., 24, 1231–1248, https://doi.org/10.5194/acp-24-1231-2024, https://doi.org/10.5194/acp-24-1231-2024, 2024
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Smoke particles are typically submicron in size and assumed to have negligible impacts at the thermal infrared spectrum. However, we show that infrared signatures can be observed over dense smoke plumes from satellites. We found that giant particles are unlikely to be the dominant cause. Rather, co-transported water vapor injected to the middle to upper troposphere and surface cooling beneath the plume due to shadowing are significant, with the surface cooling effect being the most dominant.
Farnaz Hosseinpour and Eric M. Wilcox
Atmos. Chem. Phys., 24, 707–724, https://doi.org/10.5194/acp-24-707-2024, https://doi.org/10.5194/acp-24-707-2024, 2024
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This study shows mechanistic relationships between the radiative effect of dust aerosols in the Saharan air layer and the kinetic energy of the African easterly waves across the tropical Atlantic Ocean using 22 years of daily satellite observations and reanalysis data based on satellite assimilation. Our findings suggest that dust aerosols not merely are transported by these waves but also contribute to the growth of waves through the enhancement of diabatic heating induced by dust.
Markus D. Petters, Tyas Pujiastuti, Ajmal Rasheeda Satheesh, Sabin Kasparoglu, Bethany Sutherland, and Nicholas Meskhidze
Atmos. Chem. Phys., 24, 745–762, https://doi.org/10.5194/acp-24-745-2024, https://doi.org/10.5194/acp-24-745-2024, 2024
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This work introduces a new method that uses remote sensing techniques to obtain surface number emissions of particles with a diameter greater than 500 nm. The technique was applied to study particle emissions at an urban site near Houston, TX, USA. The emissions followed a diurnal pattern and peaked near noon local time. The daily averaged emissions correlated with wind speed. The source is likely due to wind-driven erosion of material situated on asphalted and other hard surfaces.
Zhuang Wang, Chune Shi, Hao Zhang, Yujia Chen, Xiyuan Chi, Congzi Xia, Suyao Wang, Yizhi Zhu, Kaidi Zhang, Xintong Chen, Chengzhi Xing, and Cheng Liu
Atmos. Chem. Phys., 23, 14271–14292, https://doi.org/10.5194/acp-23-14271-2023, https://doi.org/10.5194/acp-23-14271-2023, 2023
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The annual cycle of dust and anthropogenic aerosols' vertical distributions was revealed by polarization Raman lidar in Beijing. Anthropogenic aerosols typically accumulate at the top of the mixing layer (ML) due to the hygroscopic growth of atmospheric particles, and this is most significant in summer. There is no significant relationship between bottom dust mass concentration and ML height, while the dust in the upper air tends to be distributed near the mixing layer.
Simone Lolli, Michaël Sicard, Francesco Amato, Adolfo Comeron, Cristina Gíl-Diaz, Tony C. Landi, Constantino Munoz-Porcar, Daniel Oliveira, Federico Dios Otin, Francesc Rocadenbosch, Alejandro Rodriguez-Gomez, Andrés Alastuey, Xavier Querol, and Cristina Reche
Atmos. Chem. Phys., 23, 12887–12906, https://doi.org/10.5194/acp-23-12887-2023, https://doi.org/10.5194/acp-23-12887-2023, 2023
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We evaluated the long-term trends and seasonal variability of the vertically resolved aerosol properties over the past 17 years in Barcelona. Results shows that air quality is improved, with a consistent drop in PM concentrations at the surface, as well as the column aerosol optical depth. The results also show that natural dust outbreaks are more likely in summer, with aerosols reaching an altitude of 5 km, while in winter, aerosols decay as an exponential with a scale height of 600 m.
Ludovico Di Antonio, Claudia Di Biagio, Gilles Foret, Paola Formenti, Guillaume Siour, Jean-François Doussin, and Matthias Beekmann
Atmos. Chem. Phys., 23, 12455–12475, https://doi.org/10.5194/acp-23-12455-2023, https://doi.org/10.5194/acp-23-12455-2023, 2023
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Long-term (2000–2021) 1 km resolution satellite data have been used to investigate the climatological aerosol optical depth (AOD) variability and trends at different scales in Europe. Average enhancements of the local-to-regional AOD ratio at 550 nm of 57 %, 55 %, 39 % and 32 % are found for large metropolitan areas such as Barcelona, Lisbon, Paris and Athens, respectively, suggesting a non-negligible enhancement of the aerosol burden through local emissions.
Sebastien Garrigues, Melanie Ades, Samuel Remy, Johannes Flemming, Zak Kipling, Istvan Laszlo, Mark Parrington, Antje Inness, Roberto Ribas, Luke Jones, Richard Engelen, and Vincent-Henri Peuch
Atmos. Chem. Phys., 23, 10473–10487, https://doi.org/10.5194/acp-23-10473-2023, https://doi.org/10.5194/acp-23-10473-2023, 2023
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The Copernicus Atmosphere Monitoring Service (CAMS) provides global monitoring of aerosols using the ECMWF forecast model constrained by the assimilation of satellite aerosol optical depth (AOD). This work aims at evaluating the assimilation of the NOAA VIIRS AOD product in the ECMWF model. It shows that the introduction of VIIRS in the CAMS data assimilation system enhances the accuracy of the aerosol analysis, particularly over Europe and desert and maritime sites.
Nabia Gulistan, Khan Alam, and Yangang Liu
EGUsphere, https://doi.org/10.5194/egusphere-2023-1865, https://doi.org/10.5194/egusphere-2023-1865, 2023
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This study investigates the influence of aerosol and meteorology on precipitating and non-precipitating clouds over Indo-Gangetic Plains (IGP). The major findings of this study include the high loading of aerosols led to a high occurrence of precipitating clouds under unstable conditions in summer. This study has the potential to open a new avenue for the scientific community to further explore and understand the complications of aerosol-cloud-precipitation over the complex topography of IGP.
Maria Filioglou, Ari Leskinen, Ville Vakkari, Ewan O'Connor, Minttu Tuononen, Pekko Tuominen, Samuli Laukkanen, Linnea Toiviainen, Annika Saarto, Xiaoxia Shang, Petri Tiitta, and Mika Komppula
Atmos. Chem. Phys., 23, 9009–9021, https://doi.org/10.5194/acp-23-9009-2023, https://doi.org/10.5194/acp-23-9009-2023, 2023
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Pollen impacts climate and public health, and it can be detected in the atmosphere by lidars which measure the linear particle depolarization ratio (PDR), a shape-relevant optical parameter. As aerosols also cause depolarization, surface aerosol and pollen observations were combined with measurements from ground-based lidars operating at different wavelengths to determine the optical properties of birch and pine pollen and quantify their relative contribution to the PDR.
Jesús Abril-Gago, Pablo Ortiz-Amezcua, Diego Bermejo-Pantaleón, Juana Andújar-Maqueda, Juan Antonio Bravo-Aranda, María José Granados-Muñoz, Francisco Navas-Guzmán, Lucas Alados-Arboledas, Inmaculada Foyo-Moreno, and Juan Luis Guerrero-Rascado
Atmos. Chem. Phys., 23, 8453–8471, https://doi.org/10.5194/acp-23-8453-2023, https://doi.org/10.5194/acp-23-8453-2023, 2023
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Validation activities of Aeolus wind products were performed in Granada with different upward-probing instrumentation (Doppler lidar system and radiosondes) and spatiotemporal collocation criteria. Specific advantages and disadvantages of each instrument were identified, and an optimal comparison criterion is proposed. Aeolus was proven to provide reliable wind products, and the upward-probing instruments were proven to be useful for Aeolus wind product validation activities.
Jianyu Zheng, Zhibo Zhang, Hongbin Yu, Anne Garnier, Qianqian Song, Chenxi Wang, Claudia Di Biagio, Jasper F. Kok, Yevgeny Derimian, and Claire Ryder
Atmos. Chem. Phys., 23, 8271–8304, https://doi.org/10.5194/acp-23-8271-2023, https://doi.org/10.5194/acp-23-8271-2023, 2023
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We developed a multi-year satellite-based retrieval of dust optical depth at 10 µm and the coarse-mode dust effective diameter over global oceans. It reveals climatological coarse-mode dust transport patterns and regional differences over the North Atlantic, the Indian Ocean and the North Pacific.
Shikuan Jin, Yingying Ma, Zhongwei Huang, Jianping Huang, Wei Gong, Boming Liu, Weiyan Wang, Ruonan Fan, and Hui Li
Atmos. Chem. Phys., 23, 8187–8210, https://doi.org/10.5194/acp-23-8187-2023, https://doi.org/10.5194/acp-23-8187-2023, 2023
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To better understand the Asian aerosol environment, we studied distributions and trends of aerosol with different sizes and types. Over the past 2 decades, dust, sulfate, and sea salt aerosol decreased by 5.51 %, 3.07 %, and 9.80 %, whereas organic carbon and black carbon aerosol increased by 17.09 % and 6.23 %, respectively. The increase in carbonaceous aerosols was a feature of Asia. An exception is found in East Asia, where the carbonaceous aerosols reduced, owing largely to China's efforts.
Mukunda M. Gogoi, S. Suresh Babu, Ryoichi Imasu, and Makiko Hashimoto
Atmos. Chem. Phys., 23, 8059–8079, https://doi.org/10.5194/acp-23-8059-2023, https://doi.org/10.5194/acp-23-8059-2023, 2023
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Considering the climate warming potential of atmospheric black carbon (BC), satellite-based retrieval is a novel idea. This study highlights the regional distribution of BC based on observations by the Cloud and Aerosol Imager-2 on board the GOSAT-2 satellite and near-surface measurements of BC in ARFINET. The satellite retrieval fairly depicts the regional and seasonal features of BC over the Indian region, which are similar to those recorded by surface observations.
Hao Fan, Xingchuan Yang, Chuanfeng Zhao, Yikun Yang, and Zhenyao Shen
Atmos. Chem. Phys., 23, 7781–7798, https://doi.org/10.5194/acp-23-7781-2023, https://doi.org/10.5194/acp-23-7781-2023, 2023
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Using 20-year multi-source data, this study shows pronounced regional and seasonal variations in fire activities and emissions. Seasonal variability of fires is larger with increasing latitude. The increase in temperature in the Northern Hemisphere's middle- and high-latitude forest regions was primarily responsible for the increase in fires and emissions, while the changes in fire occurrence in tropical regions were more influenced by the decrease in precipitation and relative humidity.
Rosemary Huck, Robert G. Bryant, and James King
Atmos. Chem. Phys., 23, 6299–6318, https://doi.org/10.5194/acp-23-6299-2023, https://doi.org/10.5194/acp-23-6299-2023, 2023
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This study shows that mineral aerosol (dust) emission events in high-latitude areas are under-represented in both ground- and space-based detecting methods. This is done through a suite of ground-based data to prove that dust emissions from the proglacial area, Lhù’ààn Mân, occur almost daily but are not always recorded at different timescales. Dust has multiple effects on atmospheric processes; therefore, accurate quantification is important in the calibration and validation of climate models.
Michail Mytilinaios, Sara Basart, Sergio Ciamprone, Juan Cuesta, Claudio Dema, Enza Di Tomaso, Paola Formenti, Antonis Gkikas, Oriol Jorba, Ralph Kahn, Carlos Pérez García-Pando, Serena Trippetta, and Lucia Mona
Atmos. Chem. Phys., 23, 5487–5516, https://doi.org/10.5194/acp-23-5487-2023, https://doi.org/10.5194/acp-23-5487-2023, 2023
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Multiscale Online Non-hydrostatic AtmospheRe CHemistry model (MONARCH) dust reanalysis provides a high-resolution 3D reconstruction of past dust conditions, allowing better quantification of climate and socioeconomic dust impacts. We assess the performance of the reanalysis needed to reproduce dust optical depth using dust-related products retrieved from satellite and ground-based observations and show that it reproduces the spatial distribution and seasonal variability of atmospheric dust well.
Jacob Z. Tindan, Qinjian Jin, and Bing Pu
Atmos. Chem. Phys., 23, 5435–5466, https://doi.org/10.5194/acp-23-5435-2023, https://doi.org/10.5194/acp-23-5435-2023, 2023
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We use the Infrared Atmospheric Sounder Interferometer (IASI) retrievals of dust variables (dust optical depth and dust layer height) and surface observations to understand the day- and nighttime variations in dust aerosols over the dust belt. Our results show that daytime dust aerosols are significantly different from nighttime, and such day–night variations are influenced by meteorological factors such as wind speed, precipitation, and turbulent motions within the atmospheric boundary layer.
Ross Herbert and Philip Stier
Atmos. Chem. Phys., 23, 4595–4616, https://doi.org/10.5194/acp-23-4595-2023, https://doi.org/10.5194/acp-23-4595-2023, 2023
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We provide robust evidence from multiple sources showing that smoke from fires in the Amazon rainforest significantly modifies the diurnal cycle of convection and cools the climate. Low to moderate amounts of smoke increase deep convective clouds and rain, whilst beyond a threshold amount, the smoke starts to suppress the convection and rain. We are currently at this threshold, suggesting increases in fires from agricultural practices or droughts will reduce cloudiness and rain over the region.
Yue Huang, Jasper F. Kok, Masanori Saito, and Olga Muñoz
Atmos. Chem. Phys., 23, 2557–2577, https://doi.org/10.5194/acp-23-2557-2023, https://doi.org/10.5194/acp-23-2557-2023, 2023
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Global aerosol models and remote sensing retrievals use dust optical models with inconsistent and inaccurate dust shape approximations. Here, we present a new dust optical model constrained by measured dust shape distributions. This new dust optical model is an improvement on the current dust optical models used in models and retrieval algorithms, as quantified by comparisons against laboratory and field observations of dust optics.
Konstantinos Michailidis, Maria-Elissavet Koukouli, Dimitris Balis, J. Pepijn Veefkind, Martin de Graaf, Lucia Mona, Nikolaos Papagianopoulos, Gesolmina Pappalardo, Ioanna Tsikoudi, Vassilis Amiridis, Eleni Marinou, Anna Gialitaki, Rodanthi-Elisavet Mamouri, Argyro Nisantzi, Daniele Bortoli, Maria João Costa, Vanda Salgueiro, Alexandros Papayannis, Maria Mylonaki, Lucas Alados-Arboledas, Salvatore Romano, Maria Rita Perrone, and Holger Baars
Atmos. Chem. Phys., 23, 1919–1940, https://doi.org/10.5194/acp-23-1919-2023, https://doi.org/10.5194/acp-23-1919-2023, 2023
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Comparisons with ground-based correlative lidar measurements constitute a key component in the validation of satellite aerosol products. This paper presents the validation of the TROPOMI aerosol layer height (ALH) product, using archived quality assured ground-based data from lidar stations that belong to the EARLINET network. Comparisons between the TROPOMI ALH and co-located EARLINET measurements show good agreement over the ocean.
María Ángeles López-Cayuela, Carmen Córdoba-Jabonero, Diego Bermejo-Pantaleón, Michaël Sicard, Vanda Salgueiro, Francisco Molero, Clara Violeta Carvajal-Pérez, María José Granados-Muñoz, Adolfo Comerón, Flavio T. Couto, Rubén Barragán, María-Paz Zorzano, Juan Antonio Bravo-Aranda, Constantino Muñoz-Porcar, María João Costa, Begoña Artíñano, Alejandro Rodríguez-Gómez, Daniele Bortoli, Manuel Pujadas, Jesús Abril-Gago, Lucas Alados-Arboledas, and Juan Luis Guerrero-Rascado
Atmos. Chem. Phys., 23, 143–161, https://doi.org/10.5194/acp-23-143-2023, https://doi.org/10.5194/acp-23-143-2023, 2023
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An intense Saharan dust outbreak crossing the Iberian Peninsula in springtime was monitored to determinine the specific contribution of fine and coarse dust particles at five lidar stations, strategically covering its SW–central–NE pathway. Expected dust ageing along the transport started unappreciated. A different fine-dust impact on optical (~30 %) and mass (~10 %) properties was found. Use of polarized lidar measurements (mainly in elastic systems) for fine/coarse dust separation is crucial.
Kyriakoula Papachristopoulou, Ioannis-Panagiotis Raptis, Antonis Gkikas, Ilias Fountoulakis, Akriti Masoom, and Stelios Kazadzis
Atmos. Chem. Phys., 22, 15703–15727, https://doi.org/10.5194/acp-22-15703-2022, https://doi.org/10.5194/acp-22-15703-2022, 2022
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Megacities' air quality is determined by atmospheric aerosols. We focus on changes over the last two decades in the 81 largest cities, using satellite data. European and American cities have lower aerosol compared to African and Asian cities. For European, North American and East Asian cities, aerosols are decreasing over time, especially in China and the US. In the remaining cities, aerosol loads are increasing, particularly in India.
Nilton Évora do Rosário, Elisa Thomé Sena, and Marcia Akemi Yamasoe
Atmos. Chem. Phys., 22, 15021–15033, https://doi.org/10.5194/acp-22-15021-2022, https://doi.org/10.5194/acp-22-15021-2022, 2022
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The 2020 burning season in Brazil was marked by an atypically high number of fire spots across Pantanal, leading to high amounts of smoke within the biome. This study shows that smoke over Pantanal, usually a fraction of that over Amazonia, was higher and resulted mainly from fires in conservation and indigenous areas. It also contributes to highlighting Pantanal's 2020 burning season as the worst combination of a climate extreme scenario and inadequately enforced environmental regulations.
Santiago Gassó and Kirk D. Knobelspiesse
Atmos. Chem. Phys., 22, 13581–13605, https://doi.org/10.5194/acp-22-13581-2022, https://doi.org/10.5194/acp-22-13581-2022, 2022
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Atmospheric particles interact with light resulting in observable optical polarization. Thus, we can learn about their composition from space. New satellite sensor technology measures full polarization of reflected sunlight. This paper considers circular polarization, an overlooked category of polarization with distinctive features that could bring new insights. We review existing literature and make novel computations to consider this previously underappreciated category of polarization.
Qingyang Xiao, Guannan Geng, Shigan Liu, Jiajun Liu, Xia Meng, and Qiang Zhang
Atmos. Chem. Phys., 22, 13229–13242, https://doi.org/10.5194/acp-22-13229-2022, https://doi.org/10.5194/acp-22-13229-2022, 2022
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We provided complete coverage PM2.5 concentrations at a 1-km resolution from 2000 to the present, carefully considering the significant changes in land use characteristics in China. This high-resolution PM2.5 data successfully revealed the local-scale PM2.5 variations. We noticed changes in PM2.5 spatial patterns in association with the clean air policies, with the pollution hotspots having transferred from urban centers to rural regions with limited air quality monitoring.
Johannes Quaas, Hailing Jia, Chris Smith, Anna Lea Albright, Wenche Aas, Nicolas Bellouin, Olivier Boucher, Marie Doutriaux-Boucher, Piers M. Forster, Daniel Grosvenor, Stuart Jenkins, Zbigniew Klimont, Norman G. Loeb, Xiaoyan Ma, Vaishali Naik, Fabien Paulot, Philip Stier, Martin Wild, Gunnar Myhre, and Michael Schulz
Atmos. Chem. Phys., 22, 12221–12239, https://doi.org/10.5194/acp-22-12221-2022, https://doi.org/10.5194/acp-22-12221-2022, 2022
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Pollution particles cool climate and offset part of the global warming. However, they are washed out by rain and thus their effect responds quickly to changes in emissions. We show multiple datasets to demonstrate that aerosol emissions and their concentrations declined in many regions influenced by human emissions, as did the effects on clouds. Consequently, the cooling impact on the Earth energy budget became smaller. This change in trend implies a relative warming.
Ukkyo Jeong, Si-Chee Tsay, N. Christina Hsu, David M. Giles, John W. Cooper, Jaehwa Lee, Robert J. Swap, Brent N. Holben, James J. Butler, Sheng-Hsiang Wang, Somporn Chantara, Hyunkee Hong, Donghee Kim, and Jhoon Kim
Atmos. Chem. Phys., 22, 11957–11986, https://doi.org/10.5194/acp-22-11957-2022, https://doi.org/10.5194/acp-22-11957-2022, 2022
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Ultraviolet (UV) measurements from satellite and ground are important for deriving information on several atmospheric trace and aerosol characteristics. Simultaneous retrievals of aerosol and trace gases in this study suggest that water uptake by aerosols is one of the important phenomena affecting aerosol properties over northern Thailand, which is important for regional air quality and climate. Obtained aerosol properties covering the UV are also important for various satellite algorithms.
Abdulaziz Tunde Yakubu and Naven Chetty
Atmos. Chem. Phys., 22, 11065–11087, https://doi.org/10.5194/acp-22-11065-2022, https://doi.org/10.5194/acp-22-11065-2022, 2022
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This study examined the source of atmospheric aerosols and their role in forming clouds and rainfall over South Africa. The research provided answers to the cause of low precipitation, mainly linked to drought and water shortages experienced over the region. Further insight into the cause of occasional flooding that occurs in other parts of the area is provided. Finally, the study described the relationship between aerosol–cloud precipitation based on observation over the region.
África Barreto, Rosa D. García, Carmen Guirado-Fuentes, Emilio Cuevas, A. Fernando Almansa, Celia Milford, Carlos Toledano, Francisco J. Expósito, Juan P. Díaz, and Sergio F. León-Luis
Atmos. Chem. Phys., 22, 11105–11124, https://doi.org/10.5194/acp-22-11105-2022, https://doi.org/10.5194/acp-22-11105-2022, 2022
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A comprehensive characterization of atmospheric aerosols in the subtropical eastern North Atlantic has been carried out in this paper using long-term ground AERONET photometric observations over the period 2005–2020 from a unique network made up of four stations strategically located from sea level to 3555 m height on the island of Tenerife. This is a region that can be considered a key location to study the seasonal dependence of dust transport from the Sahel-Sahara.
Xiaoxi Zhao, Kan Huang, Joshua S. Fu, and Sabur F. Abdullaev
Atmos. Chem. Phys., 22, 10389–10407, https://doi.org/10.5194/acp-22-10389-2022, https://doi.org/10.5194/acp-22-10389-2022, 2022
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Long-range transport of Asian dust to the Arctic was considered an important source of Arctic air pollution. Different transport routes to the Arctic had divergent effects on the evolution of aerosol properties. Depositions of long-range-transported dust particles can reduce the Arctic surface albedo considerably. This study implied that the ubiquitous long-transport dust from China exerted considerable aerosol indirect effects on the Arctic and may have potential biogeochemical significance.
Katherine T. Junghenn Noyes, Ralph A. Kahn, James A. Limbacher, and Zhanqing Li
Atmos. Chem. Phys., 22, 10267–10290, https://doi.org/10.5194/acp-22-10267-2022, https://doi.org/10.5194/acp-22-10267-2022, 2022
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We compare retrievals of wildfire smoke particle size, shape, and light absorption from the MISR satellite instrument to modeling and other satellite data on land cover type, drought conditions, meteorology, and estimates of fire intensity (fire radiative power – FRP). We find statistically significant differences in the particle properties based on burning conditions and land cover type, and we interpret how changes in these properties point to specific aerosol aging mechanisms.
David W. Fillmore, David A. Rutan, Seiji Kato, Fred G. Rose, and Thomas E. Caldwell
Atmos. Chem. Phys., 22, 10115–10137, https://doi.org/10.5194/acp-22-10115-2022, https://doi.org/10.5194/acp-22-10115-2022, 2022
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This paper presents an evaluation of the aerosol analysis incorporated into the Clouds and the Earth's Radiant Energy System (CERES) data products as well as the aerosols' impact on solar radiation reaching the surface. CERES is a NASA Earth observation mission with instruments flying on various polar-orbiting satellites. Its primary objective is the study of the radiative energy balance of the climate system as well as examination of the influence of clouds and aerosols on this balance.
Peng Xian, Jianglong Zhang, Norm T. O'Neill, Travis D. Toth, Blake Sorenson, Peter R. Colarco, Zak Kipling, Edward J. Hyer, James R. Campbell, Jeffrey S. Reid, and Keyvan Ranjbar
Atmos. Chem. Phys., 22, 9915–9947, https://doi.org/10.5194/acp-22-9915-2022, https://doi.org/10.5194/acp-22-9915-2022, 2022
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The study provides baseline Arctic spring and summertime aerosol optical depth climatology, trend, and extreme event statistics from 2003 to 2019 using a combination of aerosol reanalyses, remote sensing, and ground observations. Biomass burning smoke has an overwhelming contribution to black carbon (an efficient climate forcer) compared to anthropogenic sources. Burning's large interannual variability and increasing summer trend have important implications for the Arctic climate.
Harshvardhan Harshvardhan, Richard Ferrare, Sharon Burton, Johnathan Hair, Chris Hostetler, David Harper, Anthony Cook, Marta Fenn, Amy Jo Scarino, Eduard Chemyakin, and Detlef Müller
Atmos. Chem. Phys., 22, 9859–9876, https://doi.org/10.5194/acp-22-9859-2022, https://doi.org/10.5194/acp-22-9859-2022, 2022
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The evolution of aerosol in biomass burning smoke plumes that travel over marine clouds off the Atlantic coast of central Africa was studied using measurements made by a lidar deployed on a high-altitude aircraft. The main finding was that the physical properties of aerosol do not change appreciably once the plume has left land and travels over the ocean over a timescale of 1 to 2 d. Almost all particles in the plume are of radius less than 1 micrometer and spherical in shape.
Peng Xian, Jianglong Zhang, Norm T. O'Neill, Jeffrey S. Reid, Travis D. Toth, Blake Sorenson, Edward J. Hyer, James R. Campbell, and Keyvan Ranjbar
Atmos. Chem. Phys., 22, 9949–9967, https://doi.org/10.5194/acp-22-9949-2022, https://doi.org/10.5194/acp-22-9949-2022, 2022
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The study provides a baseline Arctic spring and summertime aerosol optical depth climatology, trend, and extreme event statistics from 2003 to 2019 using a combination of aerosol reanalyses, remote sensing, and ground observations. Biomass burning smoke has an overwhelming contribution to black carbon (an efficient climate forcer) compared to anthropogenic sources. Burning's large interannual variability and increasing summer trend have important implications for the Arctic climate.
Sudip Chakraborty, Bin Guan, Duane E. Waliser, and Arlindo M. da Silva
Atmos. Chem. Phys., 22, 8175–8195, https://doi.org/10.5194/acp-22-8175-2022, https://doi.org/10.5194/acp-22-8175-2022, 2022
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This study explores extreme aerosol transport events by aerosol atmospheric rivers (AARs) and shows the characteristics of individual AARs such as length, width, length-to-width ratio, transport strength, and dominant transport direction, the seasonal variations, the relationship to the spatial distribution of surface emissions, the vertical profiles of wind, aerosol mixing ratio, and aerosol mass fluxes, and the major planetary-scale aerosol transport pathways.
Guangyao Dai, Kangwen Sun, Xiaoye Wang, Songhua Wu, Xiangying E, Qi Liu, and Bingyi Liu
Atmos. Chem. Phys., 22, 7975–7993, https://doi.org/10.5194/acp-22-7975-2022, https://doi.org/10.5194/acp-22-7975-2022, 2022
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In this paper, a Sahara dust event is tracked with the spaceborne lidars ALADIN and CALIOP and the models ECMWF and HYSPLIT. The performance of ALADIN and CALIOP on tracking the dust event and on the observations of dust optical properties and wind fields during the dust transport is evaluated. The dust mass advection is defined, which is calculated with the combination of data from ALADIN and CALIOP coupled with the products from models to describe the dust transport quantitatively.
Ke Gui, Wenrui Yao, Huizheng Che, Linchang An, Yu Zheng, Lei Li, Hujia Zhao, Lei Zhang, Junting Zhong, Yaqiang Wang, and Xiaoye Zhang
Atmos. Chem. Phys., 22, 7905–7932, https://doi.org/10.5194/acp-22-7905-2022, https://doi.org/10.5194/acp-22-7905-2022, 2022
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This study investigates the aerosol optical and radiative properties and meteorological drivers during two mega SDS events over Northern China in March 2021. The MODIS-retrieved DOD data registered these two events as the most intense episode in the same period in history over the past 20 years. These two extreme SDS events were associated with both atmospheric circulation extremes and local meteorological anomalies that favor enhanced dust emissions in the Gobi Desert.
Manuel Gutleben, Silke Groß, Christian Heske, and Martin Wirth
Atmos. Chem. Phys., 22, 7319–7330, https://doi.org/10.5194/acp-22-7319-2022, https://doi.org/10.5194/acp-22-7319-2022, 2022
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The main transportation route of Saharan mineral dust particles leads over the subtropical Atlantic Ocean and is subject to a seasonal variation. This study investigates the characteristics of wintertime transatlantic dust transport towards the Caribbean by means of airborne lidar measurements. It is found that dust particles are transported at low atmospheric altitudes (<3.5 km) embedded in a relatively moist mixture with two other particle types, namely marine and biomass-burning particles.
Goutam Choudhury, Albert Ansmann, and Matthias Tesche
Atmos. Chem. Phys., 22, 7143–7161, https://doi.org/10.5194/acp-22-7143-2022, https://doi.org/10.5194/acp-22-7143-2022, 2022
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Lidars provide height-resolved type-specific aerosol properties and are key in studying vertically collocated aerosols and clouds. In this study, we compare the aerosol number concentrations derived from spaceborne lidar with the in situ flight measurements. Our results show a reasonable agreement between both datasets. Such an agreement has not been achieved yet. It shows the potential of spaceborne lidar in studying aerosol–cloud interactions, which is needed to improve our climate forecasts.
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Short summary
In this paper, influences of aerosol hygroscopic growth on the lidar ratio are studied. Results indicate that both the magnitude and vertical structures of the retrieved aerosol extinction coefficient (σext) profile from lidar signals are significantly biased. This study proposes a feasible method for reducing the bias of retrieving the σext profile and this method can be implemented in operational retrieval of the aerosol σext profile and for pollution monitoring.
In this paper, influences of aerosol hygroscopic growth on the lidar ratio are studied. Results...
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