The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is a high-spatial-resolution multispectral imager on the Terra satellite launched in December 1999. The ASTER thermal infrared (TIR) subsystem has five spectral bands with a spatial resolution of 90 m in the TIR spectral region, which are used for generation of the standard products of surface temperature and surface spectral emissivity. High-resolution surface emissivity at five spectral bands is unique, and is particularly useful for geological mapping. However, the emissivity product is not always easy to use, because (1) its image size is about 60 km square which is not large enough for regional-scale studies, (2) its imaged area is not fixed to the world reference system (WRS) due to a flexible pointing system, and (3) standard atmospheric correction often fails under humid conditions. Thus, in order to improve the usability of the ASTER emissivity product, Ibaraki University has produced a land surface emissivity map in global scale by applying improved retrieval algorithms and stack/mosaic processing to an ASTER orthogonal projection dataset which have been produced from the ASTER data archives by the Advanced Industrial Science and Technology (AIST), Japan.

This web site provides the emissivity map divided by a tile of 5 by 5 degrees.