Cross-Comparison of Tempest Stp-H8 and GPM/GMI Observations Over Tropical Cyclone Systems

The objective of this study is to compare microwave brightness temperature observations performed by the Temporal Experiment for Storms and Tropical Systems (TEMPEST) Space Test Program-Houston 8 (TEMPEST- H8) with those from the Global Precipitation Measurement (GPM) Microwave Imager (GMI). This study utilizes TEMPEST-H8 and GMI observations over tropical cyclones (TCs). Brightness temperature (TB) observations from the TEMPEST-H8 165 GHz channel and the GMI 166 GHz horizontal polarization channel were used in the cross-comparison study. Three tropical cyclones, including Tropical Cyclone Batsirai, Typhoon Mawar and Hurricane Hilary, occurring over a variety of oceanic regions, were analyzed. The cross-comparison results from all three cases showed that TC size and rain band structures appear similar in TEMPEST-H8 and GMI observations. The average correlation coefficient (r) values between the observations from the two instruments are 0.85 for TC Batsirai, 0.88 for Typhoon Mawar and 0.93 for Hurricane Hilary. These results demonstrate that the TEMPEST-H8 small-satellite sensor, which is nearly identical to TEMPEST-D, performs similarly to that of a traditional science mission sensor, i.e. GPM GMI.