The drought index has been developed, based on a 8.6m surface emissivity in the 8-12m MODIS channelsE). The emissivity indicates the SiO2 strength and can vary interannually by vegetation, water vapor, and soil moisture, asa potential indicator of dro...
The drought index has been developed, based on a 8.6m surface emissivity in the 8-12m MODIS channelsE). The emissivity indicates the SiO2 strength and can vary interannually by vegetation, water vapor, and soil moisture, asa potential indicator of drought conditions. In a well-vegetated region close to 10 N of the Sahel, the NormalizedDiference Vegetation Index (NDVI) showed high sensitivity, while the emissivity did not. On the other hand, the NDVIexperienced negligible variability in a poorly vegetated region near 20 N, while the emissivity reflected sensitively theeffects of atmospheric water vapor and soil moisture conditions. Seasonal variations of the emissivity (0.94-0.97) haveHere, the dryness was more severe in urban area with less vegetation than in suburban area; the two areas correspondedto the north and south of the Han river, respectively. The emissivity exhibiting a significant spatial correlation of ~0.8with the two indices can supplement their information. ......... surface emissivity, satellite, MODIS, drought index, NDVI, EVI