CMORPH融合降水产品与地面观测雨量资料估算淮河流域面雨量对比分析

Comparative analysis of area rainfall in Huaihe River Basin estimated by CMORPH-Gauge merged data and observed rain gauge data

基于CMORPH融合降水产品与地面观测雨量资料,分别采用网格算术平均法与泰森多边形法估算淮河流域15个子单元2008—2011年汛期(6—9月)逐日面雨量,并对2种面雨量估算结果进行对比统计分析。结果表明:15个子单元2种面雨量估算结果具有系统性差异,两者之间存在显著线性关系;逐日面雨量估算结果也存在系统性差异,利用地面观测雨量资料估算的面雨量普遍大于利用CMORPH融合降水产品的估算结果;2种面雨量估算结果在降水量级上有很好的对应关系,各降水量级完全对应的总体比例为78.8%,相差1个量级的比例为20.5%,其中小雨量级完全对应的比例高达91.4%。

Based on the CMORPH-Gauge merged data and observed rain gauge data, the daily area rainfall of 15 sub-catchments in the Huaihe River Basin was calculated during flood seasons （ June to September） from 2008 to 2011, using the Thiessen polygon method and the grid arithmetic average method. Comparative statistical analysis was conducted on the results of the two methods. The results show that the two sets of area rainfall of the 15 sub-catchments exhibited systematic differences and a significant linear correlation. The daily area rainfall also showed systematic difference. The area rainfall based on rain gauge data was generally greater than that based on the CMORPH-Gauge merged data. There was a strong correspondence for the magnitude between the two sets of area rainfall. The overall correspondence ratio was 78. 8%, with the ratio of rainfall values that differed by an order of magnitude being 20 . 5%. The correspondence ratio for the light-rainfall magnitude reached 91 . 4%.