Performance Evaluation of TRMM-3B43-V7 and PERSIANN-CDR Monthly Precipitation Products in Different Climatic Regions of Iran

Awareness of the spatial and temporal distribution of precipitation around the world is useful for improving climate awareness and modifying climate forecasting models. However, determining the precipitation distribution is a complex task due to the lack of a single estimator with sufficient coverage and accuracy. In this study, the performance of TRMM-3B43-V7 and PERSIANN-CDR satellite precipitation products on a monthly scale and in different climatic regions in Iran were evaluated. For this purpose, measured rainfall data were used in 81 synoptic stations located in the whole country of Iran in the period from 2008 to 2019. To more accurately evaluate the efficiency of the two products, the values ​​of the statistical indices of correlation coefficient, root mean square error, efficiency factor and false alarm ratio in the position of all synoptic stations were calculated and analyzed. The results showed that in general, TRMM has a significant advantage over PERSIANN-CDR in all statistical indicators. However, the performance of both products in rainy areas was associated with more errors. With the exception of moderate and humid regions, both products estimated more rainfall in the rest of the climatic Regions. This difference in rainfall estimates is greater in arid and semi-arid areas than in other areas.