A fine time resolution
analysis, such as the Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis
(TMPA) (Huffman et al., 2006), is the key data set for the proposed landslide monitoring system in this
study. The TMPA global rainfall map is produced by using TRMM to calibrate, or adjust, the estimates
from other satellite sensors, and then combining all the estimates into the TMPA final analysis. The
coverage of the TMPA depends on input from different sets of sensors. First, precipitation-related passive
microwave data are collected by a variety of low-Earth-orbit satellites, including the TRMM Microwave
Imager (TMI) on TRMM, Special Sensor Microwave/Imager on Defense Meteorological Satellite Program
(DMSP) satellites, Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E)
on Aqua, and the Advanced Microwave Sounding Unit B (AMSU-B) on the National Oceanic and
Atmospheric Administration (NOAA) satellite series. The second major data source for the TMPA is the
window-channel (–10.7 micron) infrared (IR) data that are being collected by the international constellation
of geosynchronous-Earth-orbit satellites, which provide excellent time-space coverage (half-hourly
4x4-km equivalent lat./long. grids) after merged by the Climate Prediction Center of the National Weather
Service/NOAA (Janowiak et al., 2001). The IR brightness temperatures are corrected for zenith-angle
viewing effects and inter-satellite calibration differences.