Because of MODIS predominant space and spectral differentiate rate,it’s has been broadly applied to various field,in the aspect of snow monitoring,MODIS has been successfully using a normalized difference snow index(NDSI)to provide global automated binary maps of snow cover.The NDSI is a spectral ratio that takes advantage of the spectral difference of snow in short-wave infrared and visible spectral bands ,although it has higher precision,it can only discern one pixel to snow or other features...