An empirical study of surface wind retrievals using the TMI over the South China Sea in the summer monsoon season

This study demonstrates the feasibility of an oceanic wind speed retrieval method: the D-matrix algorithm for local usage. The D-matrix algorithm was examined and ocean surface wind retrievals, utilizing the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI), were validated by using wind speed measurements from ocean buoys deployed over the South China Sea from April to June of 1998 as part of the South China Sea Monsoon Experiment/1998. Results showed the TMI D-matrix algorithm potentially malfunctioning in terms of no-rainfall recognition when summer monsoons prevail. In this study, assistance to its rain identification ability was conducted by using rain-screening methods for screening out non-rainfall TMI points. As to the quantitative validation, only cases of wind speed weaker than 15 m s^-1 were analyzed with a root mean square of 1.34 m s^-1. The study results are significant for local usage of the rainfall-profiling algorithm providing a scheme for estimating surface wind speeds over the South China Sea during the summer monsoon season.