GIS Modeling of the Effects of Climatic Changes on the Groundwater Recharge in the Central Western Parts of Jordan

Groundwater recharge in arid and semi-arid areas used to be calculated as a percentage of the amount of precipitation. This approach does not seem to be suitable for these areas, because soils serve as reservoirs for evaporation water that results from precipitation water and is being retained in the soil. Taking the water retained in the soil during and immediately after the rainy season into consideration and considering that it is the only water available for evaporation is a more logical approach. Accordingly, groundwater recharge in the central western parts of Jordan was calculated, and scenarios of eventual climatic changes of increasing temperatures and decreasing precipitation on the groundwater recharge were evaluated. It was found that climatic changes resulting in temperature rises by 1ºC and 2ºC will result in decreases in groundwater recharge of 11.3% and 23.2%, respectively. A decrease in precipitation by 10% and 20% will cause a reduction in groundwater recharge of 24.06% and 48.34% compared to the prevailing average conditions.