The Tropical Rainfall Measuring Mission (TRMM) is a joint U.S.-Japan satellite mission to monitor tropical and subtropical precipitation and to estimate its associated latent heating.
Hydrometeor profiles of cloud liquid water, precipitation water, cloud ice water, precipitation ice, rainfall type, and latent heating are reported in 28 layers, with a vertical resolution of 0.5 km from the surface ... to 18.0 km. Geolocation, time stamp, data quality, surface type, and surface rain confidence are included for each pixel. Spatial coverage is between 38 degrees North and 38 degrees South, owing to the 35 degree inclination of the TRMM satellite. This orbit provides extensive coverage in the tropics and allows each location to be covered at a different local time each day, enabling the analysis of the diurnal cycle of precipitation. There are, in general, 2991 scans along the orbit, with each scan consisting of 208 high resolution (85 GHz) pixels. The scan width is about 760 km.
The data are stored in the Hierarchical Data Format (HDF), which includes both core and product specific metadata applicable to the TMI measurements. A file contains a single orbit of data with a file size of about 95 MB (uncompressed). The HDF-EOS "swath" structure is used to accommodate the actual geophysical data arrays. There are 16 files of TMI 2A12 data produced per day.
An orbit boost occurred near 2001-08-08, which changed the resolution of the data.
Pre-Boost (1997-12-01 through 2001-08-07): Horizontal Resolution 4.4 km, Swath Width 760 km
Post-Boost (2001-08-24 through end of dataset): Horizontal Resolution 5.1 km, Swatch Width 878 km