Correction methods of MODIS cloud product based on ground observation data
Comparative analysis of cloud fraction obtained from Moderate-resolution Imaging Spectroradiometer (MODIS) and ground observations shows the existence of considerable deviations. Five correction methods, based on cloud fraction observed from ground meteorological stations, have been proposed in this paper, including difference correction, ratio correction, difference-mixed correction, ratio-mixed correction and normalization-mixed correction of MODIS cloud product. The results show that all of the five correction methods are workable. Comparatively, the ratio correction method has the highest precision and is easy to be implemented. Hence it is the best recommended correction method for MODIS cloud product. After correction, the cloud fraction of MODIS is identical with that of ground observations, both in spatial distribution and quantitative analysis. Furthermore, intensive observations test show that monthly Mean Absolute Bias Error (MABE) of cloud fraction obtained from MODIS after ratio correction is less than 5%. This study gives a reference for relative researches using ground observation data to correct the related satellite products, which is of great significance to the related investigations of plateau, mountains and desert with sparse stations.
NETL
NSTL
万方数据
维普
