基于GOCI卫星的大气细颗粒物PM2.5的遥感反演及其时空分布规律研究

Remote Sensing Retrieval of Atmospheric Fine Particle PM2.5 based on GOCI Satellite and Its Temporal and Spatial Distribution

随着我国经济的快速发展和城市化进程的加快,大气细颗粒物PM 2.5已经成为影响我国大气环境污染的主要因素之一。利用静止卫星数据可以获取大范围的面状PM 2.5信息,为我国大气环境的监测、治理、预测等提供了不可替代的数据源。以江苏省为研究区,利用静止卫星GOCI数据,在反演逐时气溶胶光学厚度(AOD)的基础上,结合气象因子,利用多元统计分析进行了研究区PM 2.5的遥感反演研究。结果表明:基于AOD的多元统计模型,在估计的PM 2.5浓度和观测值之间表现出良好的一致性,拟合度R 2为0.6652。在对AOD进行湿度订正后得到的dry AOD进行多元统计建模,预测的PM 2.5浓度与观测值之间的拟合度R 2达到了0.7026,证明了经过湿度订正后的“干”AOD与PM 2.5之间建立的关系更加可靠。使用GOCI反演的AOD计算PM 2.5浓度,在空间分辨率和时间分辨率上充分体现了GOCI作为静止卫星监测PM 2.5的优势。在空间分分辨率上,基于GOCI卫星获取AOD的空间分辨率为500 m,优于MODIS 10 km的AOD产品;时间分辨率上,基于GOCI获取AOD实现每日自9:00~16:00逐小时监测,优于MODIS每日两次的AOD产品。

With the rapid development of China's economy and the acceleration of urbanization,PM 2.5 has become one of the major factors affecting atmospheric environmental pollution in China.The use of geostationary satellite data can obtain a wide range of regional PM 2.5 information,providing irreplaceable data sources for China's atmospheric environment monitoring,control,and forecasting.This paper uses the geostationary satellite GOCI data,based on Aerosol Optical Depth(AOD)retrieveal,combined with meteorological factors,and uses multivariate statistical analysis to study the remote sensing retrieval of PM 2.5 in the study area.The results show that the multivariate statistical model based on AOD shows a good agreement between the estimated PM 2.5 concentration and the observed values,and the fitting degree R 2 is 0.6652.After multivariate statistical modeling of dry AOD obtained after moisture correction of AOD,the fitting degree R 2 between the predicted concentration of PM 2.5 and the observed value reached 0.7026,which proved the relationship established betweenthe“dry”AOD after the humidity correction and PM 2.5 is more reliable.The use of GOCI-retrieved AOD to calculate PM 2.5 concentration fully reflects the advantages of GOCI as a geostationary satellite in spatial resolution and temporal resolution.In terms of spatial resolution,the spatial resolution of AOD based on GOCI satellite reachs to 500 meters,which is better than MODIS 10 km AOD product.In terms of temporal resolution,hourly AOD monitoring from 9:00 to 16:00 based on GOCI can be obtained,which is better than MODIS twice daily AOD products.