MODIS Land Surface Temperature and Emissivity (MOD21)

MODIS Land Surface Temperature and Emissivity (MOD21) is an open NASA Level 2 product for land surface temperature and emissivity retrieval from MODIS thermal infrared observations ^[1]. The product uses three thermal infrared bands spanning 8400 to 12270 nm and is distributed as HDF at 1 km native ground sampling distance ^[1]. NASA Earthdata and the MODIS product catalogue provide access paths for MOD21 data discovery and download ^[1].

MOD21 fits workflows that need regional land-surface temperature context, thermal screening, or arid and semi-arid surface-temperature retrieval rather than building-scale detail ^[1]. Its 1 km spatial resolution is too coarse for direct building thermal performance assessment, but it can support city, regional, and background thermal context layers around higher-resolution observations ^[1]. The product is an orbital, open-access data source under NASA EOSDIS open data terms ^[1].