长江流域极端降水过程事件的年内分布特征

挑选2018年发生在长江流域的8次大范围降水过程，对国家信息中心二源降水融合产品和多源降水融合产品进行适用性评估。结果表明：（1）降水融合产品对长江流域降水的估算结果平均较实况数值偏小，降水量级越大估算误差也越大，多源降水融合产品与二源降水融合产品相比，估算误差绝对值平均偏小2~3 mm。（2）与二源降水融合产品相比，多源降水融合产品对5 mm以下量级降水的估算准确率提高最显著，其次对40~49.9 mm量级降水估算准确率提高较大。（3）降水融合产品对嘉陵江、岷沱江、长江中游干流区域的估测降水误差相对较小。

The Global Precipitation Climatology Project (GPCP) Monthly Analysis (New Version 2.3) and a Review of 2017 Global Precipitation

By choosing eight large-scale precipitation events in the Yangtze River Basin during 2018, we assess the applicability of two-source and multi-source precipitation merged products in Yangtze River Basin. The data are provided by National Meteorological Infor-mation Center. Results are as follows. (1) The value of precipitation merged products in the Yangtze River Basin is smaller than the observa-tion data on average. The larger the precipitation is, the larger the error is in the merged product. The absolute error in the multi-source merged product is 2-3 mm smaller than that in the two-source merged product. (2) The estimation accuracy shows that the multi-source pre-cipitation merged product has the most significant improvement in the precipitation below 5mm, compared with the two-source precipitation merged products, followed by in the range of 40-49.9 mm precipitation. (3) The estimation error of precipitation merged product in Jialing River, Mintuo River and the middle reaches of the Yangtze River are relatively small.