Validation of Global Precipitation Measurements (GPM) Over Two Different Physiographic Regions of Pakistan

This study validated the Global Precipitation Measurement (GPM, IMERG version 06), with the rain gauge data at various physiographic regions of Pakistan for a period of 07 years (i.e. 2014–2020) at average annual scale using mean monthly data. The outcomes indicated that in average annual scale, IMERG-v06 product delineated a very strong correlation coefficient (0.94 & 0.92) in low to moderate elevated areas including Nawabshah (37m) and Panjgur (968m) in the south most region, whereas moderate correlations have been observed (0.67 & 0.71) with the same low to moderate elevated region i.e. in Bannu (406m) and Balakot (995m) in north of the country. Maximum root mean square deviation (RMSD) of 2.33 mm/day was observed Balakot and minimum RMSD of 0.14 mm/day was recorded at Panjgur. This study reveals that the GPM (IMERG- V06) is a reliable source of precipitation measurement with minor and acceptable errors at different elevation regions of Pakistan.