EVALUATION OF THE EFFECT BETWEEN RAINFALL AND SOIL MOISTURE IN IRAQABSTRACT Soil moisture data improves the accuracy of remotely sensed surface soil moisture evaluations, as water resources, agriculture, climate, and ecosystems are impacted by land-atmos

Abstract

ABSTRACT Soil moisture data improves the accuracy of remotely sensed surface soil moisture evaluations, as water resources, agriculture, climate, and ecosystems are impacted by land-atmosphere interactions. This study aimed to examine the retrieved soil moisture data and its correlation with rainfall to analyze the regional interdependence between the two variables. Both soil moisture measurements from Google Earth Engine and rainfall records from ground-based stations were analyzed from the year 2000 to 2021. It was observed that the relationship between soil moisture and rainfall follows a polynomial function and that there is a strong positive correlation between the two, with a Pearson r value of 0.86, which suggests that soil moisture increases with rainfall. Additionally, the relationship was found to be climate dependent, with stronger correlations in humid and temperate regions, and weaker correlations in arid and cold climates. Regions in the north and central parts of the country, where rainfall was abundant, showed a stronger correlation as compared to the desert and arid regions with less rainfall, which showed weak or no significant correlation. Furthermore, it was discovered that during periods of heavy rainfall, there is an increase in the rate of groundwater recharge and surface water flow, which are vital for the conservation of local water resources. These outcomes emphasize the need to focus on the complex relationship between soil moisture and rainfall for efficient water resource management, particularly in areas of diverse vegetation and climates.