2000—2019年常州市MODIS气溶胶光学厚度时空变化特征研究

利用2000—2019年TERRA和AQUA相结合的气溶胶光学厚度(AOD)产品数据，从时间和空间角度分析了常州市AOD的变化特征。结果显示：(1)2012—2019年常州市PM_2.5与AOD年均值的相关系数为0.898,表明AOD产品适用于常州市气溶胶污染年际变化研究。(2)2000—2019年常州市AOD年均值范围为0.463～0.688,平均值为0.627。其中，2000—2007年常州市AOD年均值整体呈上升趋势，2011—2019年呈下降趋势。常州市AOD的月变化趋势呈倒“U”形，特征最高值出现在6月，最低值出现在12月。常州市AOD有明显的季节变化特征，夏季最高，冬季最低。(3)常州市AOD高值主要分布在西部的溧阳市金坛区，北部的新北区也存在少量高值分布。(4)通过Moran指数发现，常州市Moran指数均大于零，表明各年份AOD均呈集聚状态。2000—2010年常州市AOD的空间集聚程度较高，2010年以后的空间集聚效应逐渐减弱。空间热点分析表明，2011—2019年常州市AOD高值集聚区域相比2000—2010年有所减少，冷点集聚区域有所增加，AO...

Temporal and Spatial Variation Characteristics of MODIS Aerosol Optical Depth in Changzhou from 2000 to 2019

The aerosol optical depth product (AOD) data obtained by TERRA and AQUA from 2000 to 2019 were used to analyze the spatial and temporal variation characteristics of AOD in Changzhou.The results showed that:(1) From 2012 to 2019,the correlation coefficients between the annual average values of PM_2.5 and AOD in Changzhou were 0.898,indicating that AOD products in Changzhou are suitable for the needs of interannual research on aerosol pollution.(2) The annual mean value of AOD in Changzhou from 2000 to 2019 ranged from 0.463 to 0.688,and the average value was 0.627.The annual mean value of AOD in Changzhou from 2000 to 2007 showed an upward trend,but a downward trend from 2011 to 2019.The monthly variation of AOD in Changzhou presented an inverted U-shaped distribution,with the highest value in June and the lowest value in December;AOD had obvious seasonal changes,with the highest in summer and the lowest in winter.(3) The high values of AOD in Changzhou were mainly distributed in Jintan District of Liyang City in the western region,and high values also existed in Xinbei District in the northern region.(4) According to the Moran index analysis,Changzhou''s indexes were all greater than zero,indicating that they were concentrated in each year.The spatial agglomeration effect of AOD in Changzhou fluctuated before 2010,and gradually weakened after 2010;the spatial hot spot analysis showed that the high AOD concentration areas in Changzhou from 2011 to 2019 decreased compared with 2000 to 2010,the cold spot concentration areas increased,and the AOD value homogenization areas also increased.