为了评估GPM/IMERG产品在鲁南地区的精度，利用2016年1—12月鲁南地区35个国家气象站的降水观测数据，采用定量和分类评分指标的方法，从时间、空间和降雨强度等方面对GPM/IMERG产品在鲁南地区的适用性进行评估。结果表明：IMERG数据在鲁南地区具有较高的精度，IMERG与站点观测数据相关系数为0.8，均方根误差为5.47 mm/d，相对偏差为2.27%；从时间上来看，IMERG与站点观测区域平均日降水和月降水总体变化趋势是一致的，夏季的估算精度高于其他季节；从空间上来看，年降水量偏多的台站，IMERG数据会低估，年降水量偏少的台站，IMERG数据会高估，IMERG对中纬度山地和丘陵的估测精度优于平原；IMERG产品的估计精度与降雨强度有关，当降水量级为微量降水（小于1 mm/d）时，卫星估测能力较弱，当降水强度为小雨及以上量级时，卫星估测降水产品与实际观测概率密度差异较小；IMERG估算稳定性降水的能力较强，在降水较多月份，IMERG的探测准确率较高、空报率较低、临界成功指数较好。
Based on the precipitation data from 35 rain gauge stations of the southern Shandong Province and using the quantitative and classification score methods, the authors evaluate the applicability of GPM/IMERG products from time, space and rainfall intensity from January to December 2016. The results show that the IMERG data has high precision in the southern Shandong Province as a whole. The correlation coefficient between IMERG and site observation data is 0.8, the root mean square error is 5.47 mm/day, and the relative deviation is 2.27%. In terms of time, the IMERG data is consistent with the overall trend of average daily precipitation and monthly precipitation in the observation area of the site. The accuracy of the IMERG data in summer is better than those in other seasons. From a spatial point of view, the IMERG data will be underestimated in the areas with more annual precipitation, and overestimated in the areas with less annual precipitation. The IMERG data are more accurate in the midlatitude mountains and hill areas than those in plain in estimating. The estimation accuracy of IMERG products is related to rainfall intensity. When the precipitation level is microprecipitation (less than 1 mm/d), the IMERG estimation ability is weak. When the precipitation intensity is light rain and above, the difference between IMERG product and actual observed probability density is small. IMERG has a strong ability to estimate stable precipitation. In the months of more precipitation, the detection accuracy of IMERG is higher, the false alarm ratio is lower, and the critical success index is better.