Title
Himawari-8/AHI and MODIS Aerosol Optical Depths in China: Evaluation and Comparison
Abstract
The geostationary earth orbit satelliteHimawari-8 loaded with the Advanced Himawari Imager (AHI) has greatly enhanced our capacity of dynamic monitoring in Asia-Pacific area. The Himawari-8/AHI hourly aerosol product is a promising complementary source to the MODerate resolution Imaging Spectroradiometer (MODIS) daily aerosol product for near real-time air pollution observations. However, a comprehensive evaluation of AHI aerosol optical depth (AOD) is still limited, and the difference in performances of AHI and MODIS remains uncertain. In this study, we evaluated the Himawari-8/AHI Level 3 Version 3.0 and MODIS Collection 6.1 Deep Blue AOD products over China against AOD measurements from AErosol RObotic NETwork (AERONET) sites in a spatiotemporal comparison of the products from February 2018 to January 2019. Results showed that AHI AOD achieved a moderate agreement with AERONET with a correlation coefficient of 0.75 and a root-mean-square-error of 0.26, which was slightly inferior to MODIS. The retrieval accuracy was spatially and temporally varied in AHI AOD, with higher accuracies for XiangHe and Lulin sites as well as in the morning and during the summer. The dependency analysis further revealed that the bias in AHI AOD was strongly dependent on aerosol loading and influenced by the angstrom ngstrom Exponent and NDVI while those for MODIS appeared to be independent of all variables. Fortunately, the biases in AHI AOD could be rectified using a random forest model that contained the appropriate variables to produce sufficiently accurate results with cross-validation R of 0.92 and RMSE of 0.15. With these adjustments, AHI AOD will continue to have great potential in characterizing precise dynamic aerosol variations and air quality at a fine temporal resolution.
Year
DOI
Venue
2019
10.3390/rs11091011
REMOTE SENSING
Keywords
Field
DocType
aerosol optical depth (AOD),Himawari-8,MODIS,validation,China
Aerosol,Remote sensing,China,Geology
Journal
Volume
Issue
Citations 
11
9
0
PageRank 
References 
Authors
0.34
0
4
Name
Order
Citations
PageRank
Jiang Tingting1112.69
Bin Chen2424.93
Karen Kie Yan Chan300.34
Bin Xu413323.23