2010—2019年粤港澳地区气溶胶光学厚度时空分布特征

SPATIO-TEMPORAL DISTRIBUTION CHARACTERISTICS OF AEROSOL OPTICAL DEPTH IN GUANGDONG,HONG KONG AND MACAO FROM 2010 TO 2019

为了解粤港澳地区气溶胶光学厚度分布和时序变化规律,深入认识大气气溶胶的光学特性及其气候效应,利用2010-2019年的MODISC61AOD3km逐日产品,分析了粤港澳地区的AOD空间分布及年、季、月变化特征。(1)MODISAOD与AERONETCE318AOD最优拟合系数为0.96,与SolarSIM-D2AOD拟合系数为0.62,与PM_(2.5)、PM_(10)的最优拟合系数为0.58、0.56。(2)空间上表现为珠三角AOD值高,粤西次之,粤北及粤东北较低。(3)年变化特征整体上呈明显的下降趋势,2010-2014年AOD波动上升,至2014年达到峰值,2015年后AOD显著减小,于2016年达到最低值。(4)季节上表现为春季>夏季>秋季>冬季。(5)月变化特征表现为3月最大(AOD值:0.73),4月次之,5-8月AOD维持在高值且波动平稳,9-12月显著下降。研究显示,粤港澳地区颗粒物污染防治应以佛山、广州等珠江三角洲城市及粤西为主,重点控制春夏季高污染企业生产强度及颗粒物排放。

To understand the optical depth distribution and temporal variation characteristics of aerosol in Guangdong,Hong Kong and Macao,and to explore the optical properties of atmospheric aerosols and their effects on climate,the present study used the daily products of MODIS C61 AOD 3 km from 2010 to 2019 to analyze the spatial distribution of aerosol optical depth(AOD)in Guangdong,Hong Kong and Macao and the characteristics of its annual,seasonal and monthly variation.The results showed that:(1)The optimal fitting coefficient of MODIS AOD and AERONET CE318 AOD was 0.96,that of Solarsim-D2 AOD was 0.62,and that of PM_(2.5)and PM_(10)mass concentrations were 0.58 and 0.56,respectively.(2)Spatially,the AOD value of the Pearl River Delta was the highest,followed by that of western Guangdong,and the values of northern Guangdong and northeastern Guangdong were the lowest.(3)Annual variation showed a clear downward trend.The fluctuation of AOD increased from 2010 to 2014 and reached its peak in 2014.After 2015,AOD decreased significantly and bottomed out in 2016.(4)The seasonal pattern was as follows:spring(AOD:0.66)>summer(AOD:0.53)>autumn(AOD:0.44)>winter(AOD:0.41).(5)The characteristics of monthly variation were that the AOD value in March was the largest(AOD:0.73),followed by that in April.It remained high and fluctuated steadily from May to August,and decreased significantly from September to December.The results showed that Foshan,Guangzhou,other Pearl River Delta cities and western Guangdong are the key areas for the prevention and control of particulate matter pollution in Guangdong,Hong Kong and Macao,and the emphasis should be the control of production intensity and particulate matter emissions of high pollution enterprises in spring and summer.