Projections of climate change in the Mediterranean Basin by using downscaled global climate model outputs

Abstract

The Mediterranean Basin is one of the regions that shall be affected most by the impacts of the future climate changes on hydrology and water resources. In this study, projected future changes in mean air temperature and precipitation climatology and inter-annual variability over the Mediterranean region were studied. For performing this aim, the future changes in annual and seasonal averages for the future period of 2070-2100 with respect to the period from 1970 to 2000 were investigated. Global climate model outputs of the World Climate Research Program's Coupled Model Intercomparison Project Phase 3 multi-model dataset were used in this work. Intergovernmental Panel on Climate Change SRES A2, A1B and B1 emission scenarios' outputs were used in future climate model projections. Future surface mean air temperatures of the larger Mediterranean basin increase mostly in summer and least in winter, and precipitation amounts decrease in all seasons at almost all parts of the basin. Future climate signals for air temperature and total precipitation values are much larger than the inter-model standard deviation. Inter-annual temperature variability increases evidently in summer season and decreases in the northern part of the domain in the winter season, while precipitation variability increases in almost all parts of domain. Probability distribution functions are found to be shifted and flattened for future period compared to the reference period. This indicates that the occurrence of frequency and intensity of high temperatures and heavy precipitation events will likely increase in the future period.