基于IVW方法的MODIS AOD融合

Data Fusion of MODIS AOD Based on IVW Method

气溶胶光学厚度(Aerosol Optical Depth,AOD)受高湿、多云等气候特征的影响而造成非随机缺失,为了最大限度地扩大AOD的覆盖范围,本文以华中三省为研究区,首先基于武汉大学自测的地面AOD数据,对华中地区C 6.1中等分辨率成像光谱仪(Moderate Resolution Imaging Spectroradiometer,MODIS)反演的2010—2017年10 km DT、10 km DB以及3 km DT AOD数据的精度进行验证,然后利用逆方差加权(Inverse Variance Weighting,IVW)方法,将10 km分辨率深蓝算法反演的AOD分别和10 km、3 km分辨率暗目标算法反演的AOD融合。结果表明,融合后10 km和3 km AOD与地面实测AOD的皮尔森相关系数分别为0.83和0.86;相对于MODIS标准10 km和3 km DT数据,IVW融合后的10 km和3 km AOD的平均覆盖率分别提高55.17%和48.00%。

Satellite AOD data is often missing due to the influence of the climate characteristics such as high humidity and cloudy.For expanding the coverage of AOD,this paper takes three provinces in Central China as the research area.Firstly,the accuracy of 10 km DT,10 km DB and 3 km DT AOD data is verified based on the ground AOD data measured by Wuhan university,and then the AOD inversion of 10 km resolution deep blue algorithm is fused with the AOD inversion of 10 km resolution dark target algorithm inversion of 10 km and 3 km resolution,respectively.The Pearson correlation coefficients of the IVW combined 10 km and 3 km AOD and ground measured AOD were 0.83 and 0.86 respectively,which were significantly higher than the MODIS standard data;compared with the MODIS standard 10 km and 3 km DT data,the average coverage of IVW combined 10 km and 3 km AOD increased by 55.17%and 48.00%respectively.