Enabling technologies to map precipitation with near-global coverage and hour-scale revisit times

The Tropical Rainfall Measuring Mission (TRMM) is a joint NASA/NASDA mission intended to produce rainfall accumulation maps using a combined active radar and passive radiometer set of sensors. The TRMM orbit inclination of 35 deg limits coverage to the tropics. The single satellite limits sampling (revisit time) to at best 15 hours. A new measurement concept is presented which extends and improves on the performance of TRMM. Global, rather than tropical, coverage is provided by a polar orbit inclination. The concept is comprised of a “core” spacecraft, which is an upgraded version of TRMM, together with ~8 smaller constellation satellites which carry a subset of radiometers. Proper orbital phasing of the core and constellation satellites will improve temporal sampling to ~3 hours. An overview of the concept is presented, followed by a description of current technology development projects which are underway to enable the measurement