Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Characteristics of atmospheric aerosol optical depth variation in China during 1993–2012
Abstract The long-term variations of atmospheric aerosol optical depth (AOD) over 14 first-class solar radiation stations in China during 1993–2012 are studied. The AOD at 750 nm wavelength is retrieved with the hourly accumulated direct solar radiation by using a broadband extinction method. The retrievals are validated in comparison with AERONET (Aerosol Robotic Network) and MODIS (Moderate Resolution Imaging Spectroradiometer) AOD products. For the comparison with AERONET, the correlation coefficient (R), mean bias error (MBE) and root mean square error (RMSE) of the monthly mean AODs are respectively 0.848, 0.029 and 0.101. Based on the statistical analysis, the monthly, seasonal and annual AOD variation characteristics are categorized as follow: (1) There are three major types of the seasonal AOD variations, which shows the largest seasonal averaged AOD appearing in spring, summer and winter. The smallest seasonal averaged AOD appears mostly in autumn. (2) Beijing and Guangzhou show a significant decreasing trend of the yearly AOD, while an increasing tendency appears in Zhengzhou, Shanghai, Kunming, Kashi and Wuhan. Although no significant variation trends are found, some fluctuations appear in the 20-year period in other cities. (3) The 20-year mean AOD ranges from 0.135 (Lhasa) to 0.678 (Zhengzhou). The aerosol hygroscopic growth contributes a lot to AOD in major cities in the eastern part of China, while not in most cities in the western part. A simple correction method is applied for enhancing the relationship of AOD and PM2.5 concentration.
Highlights AOD is retrieved from broadband solar radiation in 14 cities during 1993–2012. Good agreements are found between our retrievals and AERONET and MODIS. There are three major types of the seasonal AOD variations. Yearly and seasonal mean AOD variation trends are analyzed in 14 cities. Hygroscopic growth contributes a lot to AODs in the major cities in East China.
Characteristics of atmospheric aerosol optical depth variation in China during 1993–2012
Abstract The long-term variations of atmospheric aerosol optical depth (AOD) over 14 first-class solar radiation stations in China during 1993–2012 are studied. The AOD at 750 nm wavelength is retrieved with the hourly accumulated direct solar radiation by using a broadband extinction method. The retrievals are validated in comparison with AERONET (Aerosol Robotic Network) and MODIS (Moderate Resolution Imaging Spectroradiometer) AOD products. For the comparison with AERONET, the correlation coefficient (R), mean bias error (MBE) and root mean square error (RMSE) of the monthly mean AODs are respectively 0.848, 0.029 and 0.101. Based on the statistical analysis, the monthly, seasonal and annual AOD variation characteristics are categorized as follow: (1) There are three major types of the seasonal AOD variations, which shows the largest seasonal averaged AOD appearing in spring, summer and winter. The smallest seasonal averaged AOD appears mostly in autumn. (2) Beijing and Guangzhou show a significant decreasing trend of the yearly AOD, while an increasing tendency appears in Zhengzhou, Shanghai, Kunming, Kashi and Wuhan. Although no significant variation trends are found, some fluctuations appear in the 20-year period in other cities. (3) The 20-year mean AOD ranges from 0.135 (Lhasa) to 0.678 (Zhengzhou). The aerosol hygroscopic growth contributes a lot to AOD in major cities in the eastern part of China, while not in most cities in the western part. A simple correction method is applied for enhancing the relationship of AOD and PM2.5 concentration.
Highlights AOD is retrieved from broadband solar radiation in 14 cities during 1993–2012. Good agreements are found between our retrievals and AERONET and MODIS. There are three major types of the seasonal AOD variations. Yearly and seasonal mean AOD variation trends are analyzed in 14 cities. Hygroscopic growth contributes a lot to AODs in the major cities in East China.
Characteristics of atmospheric aerosol optical depth variation in China during 1993–2012
Xu, Xiaofeng (Autor:in) / Qiu, Jinhuan (Autor:in) / Xia, Xiangao (Autor:in) / Sun, Ling (Autor:in) / Min, Min (Autor:in)
Atmospheric Environment ; 119 ; 82-94
14.08.2015
13 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
Retrieval and Validation of Atmospheric Aerosol Optical Depth From AVHRR Over China
| Online Contents | 2016
Retrieval and Validation of Atmospheric Aerosol Optical Depth From AVHRR Over China
| Online Contents | 2016