Articles | Volume 21, issue 10 
            
                
                    
                    
            
            
            https://doi.org/10.5194/acp-21-7723-2021
                    © Author(s) 2021. This work is distributed under 
the Creative Commons Attribution 4.0 License.
                the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-21-7723-2021
                    © Author(s) 2021. This work is distributed under 
the Creative Commons Attribution 4.0 License.
                the Creative Commons Attribution 4.0 License.
Variability of NO2 concentrations over China and effect on air quality derived from satellite and ground-based observations
Cheng Fan
                                            State Environment Protection Key Laboratory of Satellite Remote
Sensing, Aerospace Information Research Institute, Chinese Academy of
Sciences, Beijing 100101, China
                                        
                                    
                                            University of Chinese Academy of Sciences, Beijing 100049, China
                                        
                                    Zhengqiang Li
                                            State Environment Protection Key Laboratory of Satellite Remote
Sensing, Aerospace Information Research Institute, Chinese Academy of
Sciences, Beijing 100101, China
                                        
                                    Ying Li
CORRESPONDING AUTHOR
                                            
                                    
                                            China Academy of Culture and Tourism, Beijing International Studies
University, Beijing 100024, China
                                        
                                    Jiantao Dong
                                            School of Surveying and Land Information Engineering, Henan
Polytechnic University, Jiao Zuo, China
                                        
                                    Ronald van der A
                                            Royal Netherlands Meteorological Institute (KNMI), R&D Satellite
Observations, 3731GA De Bilt, the Netherlands
                                        
                                    
                                            Nanjing University of Information Science and Technology (NUIST),
School of Atmospheric Physics, No. 219, Ningliu Road, Nanjing, Jiangsu, China
                                        
                                    Gerrit de Leeuw
                                            State Environment Protection Key Laboratory of Satellite Remote
Sensing, Aerospace Information Research Institute, Chinese Academy of
Sciences, Beijing 100101, China
                                        
                                    
                                            Royal Netherlands Meteorological Institute (KNMI), R&D Satellite
Observations, 3731GA De Bilt, the Netherlands
                                        
                                    
                                            Nanjing University of Information Science and Technology (NUIST),
School of Atmospheric Physics, No. 219, Ningliu Road, Nanjing, Jiangsu, China
                                        
                                    
                                            China University of Mining and Technology (CUMT), School of Environment
Science and Spatial Informatics, Xuzhou, Jiangsu 221116, China
                                        
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                                                The aerosol fine-mode fraction (FMF) is an important parameter reflecting the content of man-made aerosols. This study carried out the retrieval of FMF in China based on multi-angle polarization data and validated the results. The results of this study can contribute to the FMF retrieval algorithm of multi-angle polarization sensors. At the same time, a high-precision FMF dataset of China was obtained, which can provide basic data for atmospheric environment research.
                                            
                                            
                                        Jianping Guo, Boming Liu, Wei Gong, Lijuan Shi, Yong Zhang, Yingying Ma, Jian Zhang, Tianmeng Chen, Kaixu Bai, Ad Stoffelen, Gerrit de Leeuw, and Xiaofeng Xu
                                    Atmos. Chem. Phys., 21, 2945–2958, https://doi.org/10.5194/acp-21-2945-2021, https://doi.org/10.5194/acp-21-2945-2021, 2021
                                    Short summary
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                                                Vertical wind profiles are crucial to a wide range of atmospheric disciplines. Aeolus is the first satellite mission to directly observe wind profile information on a global scale. However, Aeolus wind products over China have thus far not been evaluated by in situ comparison. This work is expected to let the public and science community better know the Aeolus wind products and to encourage use of these valuable data in future research and applications.
                                            
                                            
                                        Boming Liu, Jianping Guo, Wei Gong, Yong Zhang, Lijuan Shi, Yingying Ma, Jian Li, Xiaoran Guo, Ad Stoffelen, Gerrit de Leeuw, and Xiaofeng Xu
                                        Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-41, https://doi.org/10.5194/acp-2021-41, 2021
                                    Revised manuscript not accepted 
                                    Short summary
                                    Short summary
                                            
                                                Vertical wind profiles are crucial to a wide range of atmospheric disciplines. Aeolus is the first satellite mission to directly observe wind profile information on a global scale. However, Aeolus wind products over China were thus far not evaluated by in-situ comparison. This work is expected to let the public and science community better know the Aeolus wind products and to encourage use of these valuable data in future researches and applications.
                                            
                                            
                                        Qiaoyun Hu, Haofei Wang, Philippe Goloub, Zhengqiang Li, Igor Veselovskii, Thierry Podvin, Kaitao Li, and Mikhail Korenskiy
                                    Atmos. Chem. Phys., 20, 13817–13834, https://doi.org/10.5194/acp-20-13817-2020, https://doi.org/10.5194/acp-20-13817-2020, 2020
                                    Short summary
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                                                This study presents the characteristics of Taklamakan dust particles derived from lidar measurements collected in the dust aerosol observation field campaign. It provides comprehensive parameters for Taklamakan dust properties and vertical distributions of Taklamakan dust. This paper also points out the importance of polluted dust which was frequently observed in the field campaign. The results contribute to improving knowledge about dust and reducing uncertainties in the climatic model.
                                            
                                            
                                        Ying Zhang, Zhengqiang Li, Yu Chen, Gerrit de Leeuw, Chi Zhang, Yisong Xie, and Kaitao Li
                                    Atmos. Chem. Phys., 20, 12795–12811, https://doi.org/10.5194/acp-20-12795-2020, https://doi.org/10.5194/acp-20-12795-2020, 2020
                                    Short summary
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                                                Observation of atmospheric aerosol components plays an important role in reducing uncertainty in climate assessment. In this study, an improved remote sensing method which can better distinguish scattering components is developed, and the aerosol components in the atmospheric column over China are retrieved based on the Sun–sky radiometer Observation NETwork (SONET). The component distribution shows there could be a sea salt component in northwest China from a paleomarine source in desert land.
                                            
                                            
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the COVID-19 Lockdown on Air Quality in the Guanzhong Basin, China, Remote
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An insight into the transport pathways and source distribution,
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                        Zheng, B., Tong, D., Li, M., Liu, F., Hong, C., Geng, G., Li, H., Li, X., Peng, L., Qi, J., Yan, L., Zhang, Y., Zhao, H., Zheng, Y., He, K., and Zhang, Q.: Trends in China's anthropogenic emissions since 2010 as the consequence of clean air actions, Atmos. Chem. Phys., 18, 14095–14111, https://doi.org/10.5194/acp-18-14095-2018, 2018. 
                    
                
                        
                        Zhong, J., Zhang, X., Dong, Y., Wang, Y., Liu, C., Wang, J., Zhang, Y., and Che, H.: Feedback effects of boundary-layer meteorological factors on cumulative explosive growth of PM2.5 during winter heavy pollution episodes in Beijing from 2013 to 2016, Atmos. Chem. Phys., 18, 247–258, https://doi.org/10.5194/acp-18-247-2018, 2018. 
                    
                Short summary
                    Emission control policy in China has resulted in the decrease of nitrogen dioxide concentrations, which however leveled off and stabilized in recent years, as shown from satellite data. The effects of the further emission reduction during the COVID-19 lockdown in 2020 resulted in an initial improvement of air quality, which, however, was offset by chemical and meteorological effects. The study shows the regional dependence over east China, and results have a wider application than China only.
                    Emission control policy in China has resulted in the decrease of nitrogen dioxide...
                    
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