Towards developing a long-term high-quality intercalibrated TRMM/GPM radiometer dataset

The Global Precipitation Measurement (GPM) mission is a constellation-based satellite mission designed to produce unified precipitation retrievals from a constellation of available microwave radiometers [1]. The core observatory builds on the successes of the Tropical Rainfall Measuring Mission (TRMM) providing advances in satellite precipitation monitoring including a dual-frequency radar, increased sensitivity to frozen precipitation, and coverage over higher latitudes. The constellation approach, however, is a unique and challenging aspect of the mission that has implications for science applications far beyond global precipitation monitoring. The success of the GPM mission has led to plans to extend the constellation concept back to the launch of TRMM [2]. Advances in radiometer calibration and improved intercalibration techniques are subsequently being used to improve the quality and stability of the TRMM Microwave Imager (TMI) data record and the associated radiometer constellation for an extended high-quality radiometer data record approaching two decades.