Integrated Approach for Precipitation Assessment in Different Topography of Iraq



GPM, IMERG, Remote Sensing, Ground Weather Station, Topography


Remote sensing precipitation data is a significant tool for solving the issue of precipitation forecasting at ground weather stations since it offers the benefits of extensive spatial coverage and high spatial and temporal precision; Providing data on precipitation that is necessary for agricultural projects important in the production of crops, especially those involved in food security, because Iraq is one of the countries affected by climate change, according to the Intergovernmental Panel on Climate Change (IPCC) report. The weather ground stations provide data on the precipitation, but some stations have incomplete data and are subjected to maintenance and shutdown at multiple intervals, which causes gaps in the data which affects the studies when observing a change in precipitation. The aim of this study is an analysis of precipitation based on Global Precipitation Measurement (GPM) data variations with weather ground stations for the different topography for the period (2000-2020) for the months of precipitation. Two statistical criteria were used in this study to obtain an appropriate evaluation that links the results of precipitation and these statistical criteria are: RSME and R2. The results indicate full agreement between GPM and ground stations which is similar to those obtained in this study. The annual accumulated correlation values ranged (from 0.51 to 0.875) for different topography between ground weather stations and GPM. The GPM data ability to detect precipitation is influenced by its height and intensity. This paper offers recommendations for using GPM IMERG precipitation products in hydrological research and managing Iraq's water resources.

Author Biographies

Thair S. Khayyun , Civil Engineering Department, University of Technology

  • Professor doctor in water resources engineering 
  • Professor at University of Technology

Imzahim A. Alwan, Civil Engineering Department, University of Technology

  • PhD in Remote Sensing Engineering
  • Professor (Full) at University of Technology, Iraq


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How to Cite

Jabal, Z. K., Khayyun, T. S., & Alwan1, I. A. (2023). Integrated Approach for Precipitation Assessment in Different Topography of Iraq. Journal of Water Resources and Geosciences, 2(1), 1–22. Retrieved from