The latest MODIS aerosol optical depth (AOD) retrieval algorithm (C005) for both Terra and Aqua has gradually ...
Lili Wanga, Yuesi Wanga,Jinyuan Xina, Zhanqing Lib, Xiaoyuan Wanga aLAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, PR China bDepartment of Meteorology, The University of Maryland, College Park, MD 20782, USA
Aerosol observational data at 8 ground-based observation sites in the Chinese Sun Hazemeter Network (CSHNET) were analyzed to characterize the optical properties of aerosol particles during the strong dust storm of 16-21 April 2005. The observational aerosol optical depth (AOD) increased significantly during this dust storm at sites in Beijing city (86%), Beijing forest (84%), Xianghe (13%), Shapotou (27%), Shenyang (47%), Shanghai (23%), and Jiaozhou Bay (24%). The API (air pollution index) in Beijing and Tianjin also had a similar rise during the dust storm, while the Angstrhm exponent (a) declined evidently at sites in Beijing city (21%), Beijing forest (39%), Xianghe (19%), Ordos (77%), Shapotou (50%), Shanghai (12%), and Jiaozhou Bay (21%), respectively. Furthermore, The observational AOD and a demonstrated contrary trends during M1 storm stages (pre-dust storm, dust storm, and post-dust storm), with the AOD indicating an obvious "Valley Peak-Valley" pattern of variation, while a demonstrated a "Peak-Valley- Peak" pattern. In addition, the dust module in a regional climate model (RegCM3) simulated the dust storm occurrence and track accurately and RegCM3 was able to basically simulate the trends in AOD. The simulation results for the North China stations were the best, and the simulation for dust-source stations was on the high side, while the simulation was on the low side for coastal sites.
The Chinese Sun Hazemeter Network (CSHNET) provides the necessary ground-based observation to validate and assess the applicability of MODIS aerosol optical depth (AOD) products over different ecological and geographic regions in China for the first time. The validation results show that the comprehensive utilization ratio and applicability of MODIS products varied very much over different regions and seasons from August 2004 to July 2005. On the Tibetan Plateau, the comprehensive utili- zation ratio of MODIS data was low: MODIS products only accounted for 16% of the ground-based observation; on average, 31% to 45% of MODIS products fell within the retrieval errors issued by NASA. A similar result was found in northern desert areas with the ratio of MODIS to observation ranging from 15% to 55%, with 7% to 39% of MODIS products within errors. In the remote northeast corner of China, low ratios of MODIS to observation were also found ranging from 14% to 46%, with 49% to 69% of MODIS within errors. The forested sites exhibited moderate ratios of MODIS to observation ranging from 46% to 65%, with 30% to 59% of MODIS within errors. This was similar to numbers observed at sites along eastern seashore of China and inland urban sites with the ratio of MODIS to observation between 63% to 75%, with 25% to 67% of MODIS within errors for sites along eastern seashore of China and 43% to 78%, with 35% to 75% of MODIS within errors for inland urban sites. The ratio of MODIS to observation over agricultural areas ranged from 61% to 89%; 59%-88% of MODIS fell within the retrieval errors. At homogeneous and well vegetated areas, the comprehensive utilization ratio of MODIS products was over 80% and above 70% of MODIS products fell within the retrieval errors in growing season.
WANG LiLiXIN JinYuanWANG YueSiLI ZhanQingWANG PuCaiLIU GuangRenWEN TianXue
<正>Aerosol observational data spanning three years(2005-2007) from the Chinese Sun Hazemeter Network(CSHN) wer...
Wupeng Du~a,Jinyuan Xin~a,Mingxing Wang~a,Qingxian Gao~b,Zhanqing Li~c,Yuesi Wang~(a,*) a Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,PR China b Chinese Research Academy of Environment Science,Beijing 100012,PR China c Department of Meteorology,The University of Maryland,College Park,MD 20782,USA