TRMM卫星反演降水在江苏典型平原区的评估与订正

Evaluation and Correction of TRMM Satellite-retrieved Precipitation in the Typical Plain Area of Jiangsu Province

卫星反演降水由于具有较高的时空分辨率,在大气、水文、生态等研究中起到越来越重要的作用,评估和订正卫星反演降水也成为研究热点之一。以江苏省为研究区域,以雨量站观测降水数据为基础,分析TRMM 3B42卫星降水产品在典型平原区的误差特性,并基于月水量平衡和逐步订正的基本原理订正其系统误差和随机误差。结果表明,原始的TRMM卫星降水数据和地面测站数据相关性较好,但在量值上存在明显误差。订正之后的TRMM卫星降水绝对误差和相对误差在量值和空间分布上均改善明显,均方根误差显著减小,确定性系数也有所提高。经过误差订正后的降水数据综合考虑了TRMM卫星空间分布的合理性和站点观测的精确性,提高了卫星反演降水的精度。研究成果为TRMM卫星降水数据在其他地区的应用提供了参考。

Satellite-retrieved precipitation has been playing more and more important role in the study of atmosphere,hydrology and ecology due to its high temporal and spatial resolution,and the evaluation and correction of satellite-retrieved precipitation has become one of the research hot spots.The error characteristics of TRMM 3B42satellite-retrieved precipitation in the typical plain were analyzed based on the gauged precipitation of Jiangsu Province,and the systematic and random error were revised based on the monthly water balance and the successive iterative correction method.Results show that the absolute and relative errors of the corrected TRMM satellite-retrieved precipitation are improved significantly in both magnitude and spatial distribution.And the root mean square error is significantly reduced.Besides,the deterministic coefficient is improved.The corrected precipitation can comprehensively consider the rationality of the spatial distribution of TRMM and the accuracy of site observation so as to improve the accuracy of satellite-retrieved precipitation.This study provides an important reference for the application of TRMM 3B42satellite-retrieved precipitation in other areas.