Changes in temperature and precipitation extremes over Western Asia: A regional ensemble from CMIP6

Abstract

This study investigates the impacts of climate change on temperature and precipitation extremes in eight West Asian countries (Iran, Afghanistan, Pakistan, Turkmenistan, Azerbaijan, Armenia, Turkey, and Iraq) using a regional ensemble of CMIP6 models. Ten models were evaluated based on their performance in simulating historical temperature and precipitation using the KGE index. Four climate extreme indices (T_max, P_max, TX90p and R95p) were employed to assess changes in temperature and precipitation extremes in the study area. The analysis of climate extremes reveals significant projected changes. T_max is expected to increase in all countries, with the most pronounced rise anticipated in Turkmenistan, where T_max in the main part of the country is projected to increase by more than 5 °C under the SSP585. Projections for P_max show a more nuanced picture. Pakistan is expected to experience the highest overall P_max. TX90p is projected to increase in all countries, indicating a rise in the frequency of extreme heat events. Pakistan is expected to experience the most significant increase in TX90p, reaching up to 36.1 % under the SSP585 (FF) scenario by 2074, followed by Iran and Afghanistan. R95p does not show a clear future trend. Pakistan is anticipated to see the highest increase in R95p, reaching up to 15.2 mm under the SSP585 scenario by 2074, while Turkey might experience a decrease of up to 7.8 mm under the SSP245 scenario. These findings highlight the diverse and concerning impacts of climate change on temperature and precipitation extremes across West Asia. The projected increase in T_max, TX90p and potential shifts in precipitation patterns pose significant challenges for the region. This study emphasizes the need for region-specific adaptation strategies to address the multifaceted challenges of climate change in West Asia.