Document Type : Original Article

Authors

• Ramyar Yusef Nejad ¹
• Manouchehr Faraj Zadeh
• Yousef Gavidel Rahimi ²

¹ Physical Geography Department, Tarbiat Modares University

² Physical Geography department, Tarbiat Modares university

Abstract

Precipitation is the most important factor in the hydrological cycle, which has many temporal and spatial changes. The use of satellite precipitation data can be of great use in climatic and hydrological research, especially in areas without rainfall statistics. Over the past three decades, a large number of satellite-derived global precipitation datasets have been developed and used. The purpose of the current research is to investigate the accuracy of the satellite precipitation data of the PERSIANN family products, which includes: PERSIANN, PERSIANN-CCS, PERSIANN-CDR and PERSIANN-PDIR. For this purpose, the daily, monthly and annual data of these products were compared with the observational data of 129 meteorological stations in Iran and in the period of 2008-2022. The evaluation of the accuracy of satellite precipitation data was done using CC and RMSE statistical indices and POD, FAR, CSI, HSS and KSS Categorical metrics. The results on a daily scale indicate the better efficiency of the PERSIANN-PDIR source with correlation and RMSE is 0.30 and 3.4 mm respectively and better performance in POD, CSI and KSS indices. In the monthly and annual scale, PERSIANN-CDR has the best estimation in monthly and annual precipitation with correlation values of 0.81, 0.78 and RMSE 23.4 and 152.7 mm. The PERSIANN source has an underestimation of annual precipitation and the PERSIANN-CCS source also has an overestimation of precipitation. However, in the high rainfall areas located in the northern belt and the Zagros mountain range, PERSIANN family products reported the annual rainfall lower than the actual amount and perform better on a monthly scale than on a daily and annual scale.

Keywords

• Keywords: Precipitation
• Iran
• PERSIANN Family
• Statistical Indices
• Classification Indices

Main Subjects

• Climatology