Assessing The Accuracy of Satellite Rainfall Data for Erbil city

Water resources for drinking and agriculture in Erbil are largely dependent on precipitation. This creates a critical need to understand the rainfall dynamics at the local scale. However, the region has a sternly sparse and unreliable rain gauge network. In areas with limited ground data like Kurdistan, satellite estimates offer a practical alternative. Validating CHIRPS data can improve rainfall monitoring.This study examines whether CHIRPS satellite data can effectively replace ground station data for modelling rainfall in Erbil. this study aims to evaluate the use the CHRIPS satellite gridded dataset as alternative source of rainfall estimate for local rainfall modeling in Erbil city. Complete, continuous, and reliable in situ station observations from the period 2014 to 2023 were used to compare against CHRIPS satellite data for the same timeframe. Rainfall value were extracted from both the interpolated in situ station surface and CHRIPS dataset at 5km intervals, covering distance the nearest station to maximum radius of 5km, to facilitate a detailed comparison. And make a production for location. Results of the nearest point were adopted for the evaluation as it’s closer to the optimal rain gauge coverage of 5 km. They show the R2 = 0.942, NSE = 0.91, PBIAS = 5.6 and RSR = 0.3.This attests that the CHIRPS satellite gridded datasets provide a good approximation and simulation of in situ station data with high collinearity and minimum deviation. CHIRPS satellite gridded rainfall estimates are therefore able to provide comprehensive rainfall estimation at a local scale. Essentially, these results contribute to scientific research in regions like Kurdistan, where rain gauge networks are sparse and characterized by incomplete, inconsistent, and unreliable data, by providing an empirically validated alternative source for rainfall estimation data.