多源融合降水实况产品在日照市暴雨过程中的适用性

Applicability of multi-source precipitation merging products during rainstorms in Rizhao

为评估融合降水实况产品在日照市的适用性,以日照市气象和水文降水观测数据为检验源,对2019—2021年5—10月和2022年5—7月融合降水数据以及发生在该时段内的25次暴雨过程进行评估检验。结果表明:(1)融合降水和观测降水空间分布一致性较好,融合降水产品可以在无降水观测地区提供参考。(2)融合降水和观测降水时间序列一致性较好,相关系数在0.9以上,长序列评估的均方根误差各月均在1.0 mm以内。平均值误差和均方根误差长序列评估结果均随着小时雨强的增大而增大。(3)融合降水存在对暴雨过程降水量和短时强降水的低估,两者差值随着小时雨强的增大而增大,当融合降水大于或小于观测降水时,两者差值较小或较大;在对暴雨极值点评估中融合降水较观测降水偏小,极值差异多在±20 mm以内。

In order to evaluate the applicability of the fused precipitation products in Rizhao City,the 25 rainstorm processes occurring from May to October in 2019 to 2021 and from May to July in 2022 were evaluated and tested using the observed precipitation data of hydrological and Meteorological departments in Rizhao City.The results show that:(1)the spatial distribution of fused and observed preeipitation is of good consistency,and the integrated precipitation products can provide a reference in areas without precipitation observations.(2)The time series of fused precipitation and observed precipitation have good consistency,with correlation coefficients above 0.9,and the root mean square errors of the long series evaluations are all within 1.0 mm in each month.Both the mean error and the root-mean-square error of the long-series assessment results increase with the increase of hourly rainfall intensity.(3)The fusion preeipitation underestimates the precipitation in the rainstorm process and short-term heavy precipitation,and the difference between the two increases with the increase of hourly rainfall intensity.When the fused precipitation is larger/smaller than the observed precipitation,the difference between the two is smaller/larger;in the evaluation of extreme points of rainstorms,the fusion precipitation is smaller than the observed precipitation,and the difference of extreme values is mostly within±20 mm.