タイトル | Rainfall Estimation Over Tropical Oceans |
著者(英) | Yoo, Jung-Moon; Short, David A.; Dalu, G.; Schols, J. L.; Weinman, J. A.; Meneghini, R.; Cuddapah, Prabhakara; Cadeddu, Maria |
著者所属(英) | NASA Goddard Space Flight Center |
発行日 | 1997-01-01 1997 |
言語 | eng |
内容記述 | Multichannel dual polarization microwave radiometer SSM/I observations over oceans do not contain sufficient information to differentiate quantitatively the rain from other hydrometeors on a scale comparable to the radiometer field of view (approx. 30 km). For this reason we have developed a method to retrieve average rain rate over a mesoscale grid box of approx. 300 x 300 sq km area over the TOGA COARE region where simultaneous radiometer and radar observations are available for four months (Nov. 92 to Feb. 93). The rain area in the grid box, inferred from the scattering depression due to hydrometeors in the 85 Ghz brightness temperature, constitutes a key parameter in this method. Then the spectral and polarization information contained in all the channels of the SSM/I is utilized to deduce a second parameter. This is the ratio S/E of scattering index S, and emission index E calculated from the SSM/I data. The rain rate retrieved from this method over the mesoscale area can reproduce the radar observed rain rate with a correlation coefficient of about 0.85. Furthermore monthly total rainfall estimated from this method over that area has an average error of about 15%. |
NASA分類 | Meteorology and Climatology |
権利 | Copyright |
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