Seasonal variations in aerosol optical properties over China
The seasonal variations in background aerosol optical depth(AOD)and aerosol type are investigated over various ecosystems in China based upon three years” worth of meteorological data and data collected by the Chinese Sun Hazemeter Network. In most parts of China，AODs are at a maximum in spring or summer and at a minimum in autumn or winter. Minimum values(0.10～0.20)of annual mean AOD at 500 nm are found in the Qinghai-Tibetan Plateau，the remote northeast corner of China，the northern forest ecosystems and Hainan Island. Annual mean AOD ranges from 0.25 to 0.30 over desert and oasis areas as well as the desertification grasslands in northern China; the annual mean AOD over the Loess Plateau is moderately high at 0.36. Regions where the highest density of agricultural and industrial activities are located and where anthropogenic sulphate aerosol and soil aerosol emissions are consistently high throughout the whole year(e.g. the central-eastern，southern and eastern coastal regions of China)experience annual mean AODs ranging from 0.50～0.80. Remarkable seasonal changes in the main types of aerosol over northern China(characterized by the Angstrom exponent，α)are seen. Due to biomass and fossil fuel burning from extensive agricultural practices in northern rural areas，concentrations of smoke and soot aerosols rise dramatically during autumn and winter(high α)，while the main types of aerosol during spring and summer are dust and soil aerosols(low α). Over southeast Asia，biomass burning during the spring leads to increases in smoke and soot emissions. Over the Tibetan Plateau and Hainan Island where the atmosphere is pristine，the main types of aerosol are dust and sea salt，respectively.
Seasonal variations optical propertie aerosol optical depth aerosol
Yuesi Wang Yang Sun Jinyuan Xin Zhanqing Li Shigong Wang Pucai Wang Wei Min Hao Bryce L. Nordgren Hongbin Chen Lili Wang
LAPC,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,P.R.China Department of Meteorology,The University of Maryland,College Park,MD 20782,USA College of Atmospheric Science,Lanzhou University,Lanzhou 730000,P.R.China USDA Forest Service,Fire Sciences Laboratory,Missoula,MT 59808,USA
国内会议
北京
英文
1-17
2008-11-20（万方平台首次上网日期，不代表论文的发表时间）