基于小波多分辨率分析的环渤海地区TRMM 3B42数据校正

Improvement of TRMM 3B42 Precipitation Estimate over Circum-Bohai-Sea Region Based on Wavelet Multi-resolution Analysis

利用环渤海地区1998-2014年55个气象站点的日降水资料,基于小波多分辨率分析方法对TRMM3B42卫星降水产品进行订正,并分析订正后3B42数据的降水估算精度.结果表明：订正后的3B42数据与站点降水数据之间的相关系数显著提高,MAE、RMSE则明显降低;订正后的3B42数据对日降水事件的探测成功率得到提高,错报率有所下降;小波多分辨率分析方法有效提高了3B42数据对各季节,特别是冬季日降水的估算精度;但,订正后的3B42数据对日降水量仍存在一定的高估现象.

Wavelet multi-resolution analysis is applied to improve TRMM 3B42 daily rainfall estimation at 55 meteorological station over the Circum-Bohai-Sea Region during 1998 ~ 2014. The results show： 1） After correction,the correlation coefficient between 3B42 and in-situ data is remarkably increased while both MAE and RMSE are decreased significantly. 2） The probability of detection and the false alarm ratio of daily precipitation event by 3B42 data are improved significantly through wavelet-based correction. 3） Wavelet multi-resolution analysis effectively enhances the precipitation estimation accuracy of each season,especially in winter. 4） Nevertheless,overestimation of corrected daily 3B42 data is still observed.