Evaluation of different gridded precipitation products in trend analysis of precipitation features over Iran

Acta Geophysica

article

Shobeiri, Shahin¹  Sharafati, Ahmad¹  Neshat, Aminreza² 

[1] Department of Civil Engineering, Science and Research Branch, Islamic Azad University;Department of GIS/RS, Faculty of Natural Resources and Environment, Science and Research Branch, Islamic Azad University

关键词: Precipitation;    Gridded precipitation product;    Trend analysis;    Mann–Kendall test;   

DOI  :  10.1007/s11600-021-00595-5

学科分类：地球科学(综合)

来源: Polska Akademia Nauk * Instytut Geofizyki

【 摘 要 】

In recent years, gridded precipitation products have been widely used in hydrology studies and other fields of water sciences. This study evaluated the potential of several gridded precipitation products, including GPCC, TRMM, CRU, ERA-Interim, and ERA5, in trend analysis of precipitation depth and the number of rainy days in various regions of Iran. Moreover, the observational precipitation data of the daily time series were collected from 68 Iranian synoptic stations. The Mann–Kendall test was conducted to determine gridded and observed precipitation trends in the period of 1997 to 2017. The probability of detection (POD) and false alarm ratio (FAR) indices were utilized to compare gridded and observed precipitation trends. Results showed that the best consistency (POD: 52% ~ 80%, FAR: 60% ~ 88%) was observed between the observed trends of the number of rainy days and those obtained by TRMM product over different regions of Iran. Moreover, ERA-Interim offered a better performance (POD: 50% ~ 100%, FAR: 58% ~ 72%) in the trend analysis of precipitation depth in Iran. The consistency between observational and gridded precipitation trends has never been analyzed in Iran at this level; therefore, this is considered a unique analysis. Besides, the generated maps of precipitation products' performance provide a comprehensive view of better water resources management over different regions of Iran.

【 授权许可】

Unknown