为了探究多源加权集成降水数据集(MSWEP)降水产品在秦巴山区的适应性,利用秦巴山区范围内站点降水观测资料,应用相关系数(CC)、均方根误差(RMSE)、平均绝对误差(MAE)以及相对偏差(Bias)等指标,对秦巴山区MSWEP降水数据精度进行评估,并分析了MSWEP降水与站点降水多年变化。结果 表明:MSWEP降水产品在秦巴山区精度较高,具有较好的实用性,无论是年、季节、月尺度还是单个站点的精度评估,相关系数(CC)都在0.8以上,具有较高的一致性; 从均方根误差(RMSE)和平均绝对误差(MAE)来看,MSWEP降水数据与站点实测值较接近; 从相对偏差(Bias)来看,MSWEP降水产品对实测值存在微弱的低估或高估。36年来,除MSWEP数据春季呈增加趋势外,其余时段两种降水量均呈减少趋势; 整个时段内,两种降水均呈“增多—减少”两个阶段变化,突变年份均发生在1985年; 并且存在明显的“丰—枯”交替变化周期,其变化主周期都为中长时间周期,都是20年以上的时间尺度,其中站点实测数据的变化主周期比MSWEP降水产品数据短2年。
To explore Multi-Source Weighted-Ensemble Precipitation(MSWEP)precipitation product adaptability in Qinbashan Mountains, precipitation observation data within the use scope of Qinbashan Mountains sites, the correlation coefficient(CC), root mean square error(RMSE), mean absolute error(MAE), and the relative deviation(Bias), and other indicators were used to evaluate MSWEP precipitation data accuracy, and analyze the site MSWEP precipitation and precipitation change for years. The results show that MSWEP precipitation product is of high precision and good practicability in Qinbashan Mountains area. Whether it is annual, seasonal, monthly scale or single site accuracy evaluation, the CC is above 0.8 with high consistency. With respect to RMSE and MAE, the MSWEP precipitation data is close to the measured value of the site. From the perspective of relative Bias, MSWEP precipitation product slightly underestimates or overestimates the measured value. In the past 36 years, except for the MSWEP data, which showed the increasing trend in spring, the precipitation of the other two periods showed the decreasing trend. During the whole period, both kinds of precipitation showed two stages of ‘increase—decrease', and the abrupt year occurred in 1985. In addition, there is an obvious ‘rich—dry' alternating change cycle, and the main change cycle is medium and long time period, which is more than 20 years. Among them, the main change cycle of site measured data is 2 years shorter than MSWEP precipitation.
