Comparison of TRMM-Derived Rainfall Products for General and Extreme Rains over the Maritime Continent

Abstract

roperties of the rain estimation differences between Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) 2A25, Microwave Imager (TMI) 2A12, and TRMM Multisatellite Precipitation Analysis (TMPA) 3B42 are investigated with a focus on distinguishing between non-extreme and extreme rains over the Maritime Continent (MC) from 1998-2014. Statistical analyses of collocated TMI1B11 85 GHz polarization-corrected brightness temperatures (PCTs), PR2A23 storm top heights, and PR2A25 vertical rain profiles are conducted to identify possible sources of the differences. The results indicate that a large estimation difference exists between PR and TMI for the general rain rate (extreme and non-extreme events). The PR-TMI rain rate differences are larger over land and coast than over ocean. When extreme rain is isolated, a higher frequency of occurrence is identified by PR over ocean, followed by TMI and TMPA. Over land, TMI yields higher rain frequencies than PR with an intermediate range of rain rates (between 15 mm h?1 and 25 mm h?1), but it gives way to PR for the highest extremes. The turnover at the highest rain rates arises because the heaviest rain depicted by PR does not necessarily accompany the strongest ice-scattering signals, which TMI relies on for estimating precipitation over land and coast.