多卫星降水产品在环渤海地区的精度评价

降水是全球能量和水循环中的重要变量之一,降水资料的精度对洪旱灾害的监测与预报、水资源管理等至关重要.本文利用环渤海地区1998—2014年55个气象站点的逐日降水数据,分别从日、月尺度对TRMM 3B42、CMORPH、PERSIANN 3种卫星降水产品进行精度评价,并对其季节差异进行分析.结果表明: 总体上,TRMM 3B42 V7的精度最高,PERSIANN精度最低,但CMORPH对日降水事件的探测成功率(0.69)最高;3B42略高估算了日降水量,其他两者则对日降水量存在低估.春、夏、秋季各卫星降水产品对降水的成功探测率高于冬季,且相关系数、均方根误差等指标随季节变化明显.3种卫星降水产品的月尺度估算精度优于日尺度,其中对日降水量的估算精度较低,特别是明显低估了暴雨事件的实际降水量.本研究为卫星降水产品在环渤海地区降水估算及其在气候与水文模拟和预测中的应用提供了依据和支持.

Accuracy evaluation of multi-satellite precipitation products over Circum-Bohai-Sea Region.

Precipitation is a key variable of the global energy and water cycle. The accuracy of precipitation data is essential for monitoring and forecasting flood and drought, as well as water resources management. Based on daily precipitation data of 55 meteorological stations over Circum-Bohai-Sea region during 1998-2014, the accuracy was evaluated and compared among 3 satellite-based precipitation products, i.e., TRMM 3B42 V7, CMORPH, and PERSIANN from daily to monthly scale. Their errors were quantified for different seasons. Results showed that generally, TRMM 3B42 V7 had the best performance while PERSIANN had the largest error. However, CMORPH had the highest detection rate of rainfall events. The rainfall was slightly overestimated by 3B42 V7 but underestimated by CMORPH and PERSIANN. Seasonally, the skill score in summer was higher than that in other seasons, and the capturing capability was much lower in winter. Meanwhile, the correlation coefficient and root mean square error varied with seasons. The performance of 3 satellite-based precipitation products increased from the daily to monthly scale. Larger errors still existed in the daily rainfall estimates, and especially the rainstorm was seriously underestimated. This study provided a basis for the use of satellite precipitation products in precipitation estimation and its application in climate and hydrological simulation over Circum-Bohai-Sea region.