黄渤海大气气溶胶卫星观测与长期变化趋势分析

Satellite Observation of Atmospheric Aerosol Over Yellow and Bohai Seas and EMD Analysis of Its Long-term Variation

收集了中国黄渤海区域（112°-125°E,35°-45°N）2000—2009年10 a内MODIS气溶胶光学厚度AOD月均标准数据,按陆地和海洋（陆海）像元及海洋像元两类分别进行经验模态分解（EMD）,结合南方涛动指数（SOI）和我国年度化石燃料消耗总量讨论黄渤海海区气溶胶时间变化特征及成因。研究表明该陆海区域大气气溶胶光学厚度6月份多为全年最高,海洋区域最高值出现在4—7月之间;秋冬季（10—次年2月）气溶胶光学厚度达到最低;EMD分解获得气溶胶具有4 a变化周期特性,与南方涛动指数的相关性均达到0.7,说明大气气溶胶同样受到全球气候变化的影响;与我国煤炭化石年消耗量相关系数达到0.98,该研究区气溶胶受陆源影响明显,人类活动对海洋环境的作用不容忽视。

The monthly averaged standard MODIS data（2000-2009） of atmospheric aerosol optical depth（AOD） over the Yellow Sea and the Bohai Sea（112°～125°E,35°～45°N） are collected,and the empirical mode decomposition（EMD） method are used to analyze respectively AOD over the land/ocean boundary area and AOD over the ocean area.In addition to AOD data,Southern oscillation index（SOI） and annual coal-consumption amount of China are also utilized to discuss the aerosal time variation and its causality over the Yellow Sea and the Bohai Sea.It is learnt from the study that AOD over the boundary area reaches its maximum in June while the AOD maximum over the ocean area appears sometime in the period from April to July.AOD fall down to its minimum in autumn and winter,i.e.in the period from October to February of the following year.It is also learnt from the EMD analysis results that aerosol over the whole studied area has its 4-year periodicity,and the correlation between the aerosol variation and the SOI variation is about 0.7,implying some effects of the global climatic variation on aerosol.The correlation between the aerosol variation and the coal consumption amount is 0.98,which means the former is greatly impacted by the source from land.Therefore it may not be ignored that human activities exert their impacts on the environments.