Investigating the Future Precipitation Changes Over the Kingdom of Bahrain Using CMIP6 Projections

Abstract Understanding precipitation projections on the grounds of climate change in arid environments is crucial for water resource planners. This study investigates the behavior of precipitation projections over the Kingdom of Bahrain using six Global Circulation Models (GCMs) from the current Coupled Model Intercomparison Project (CMIP6) archive. The ranking of six GCMs is assessed using a compromise programming technique and validated using a comprehensive rating index. Considering the results from the performance statistics, a multi-model ensemble is made for monthly and annual assessments. The 62-year period (1961–2023) is chosen as the observed data period, and further evaluations were conducted by dividing 46 years into three future periods (near-future (2024–2040), medium-future (2041–2055), and far-future (2056–2070). Precipitation projections indicate a chance of an increase of 12% in mean annual precipitation, although not statistically significant. The number of days with at least 10 mm precipitation is projected to increase, whereas there is little expectation of continuous wet days for Bahrain. The country can expect a marginal increase in the intensity of precipitation. More intense precipitation will occur for 5–10 years of return period interval. The study highlights the importance of suitable climatic model selections and the expected changes in the magnitude and intensity of precipitation in the country. This will help to formulate context-specific adaptation strategies for climate change in the Kingdom of Bahrain. Graphical Abstract