아세안

Iran, characterized by an arid to semi-arid climate, exhibits a complex precipitation pattern due to diverse topography and multiple precipitation sources. Extreme climate events and precipitation depths are assessed with minimal uncertainties, considering three uncertainty sources of general circulation models (GCMs), future scenarios, and downscaling method. The frequency, duration, severity, and intensity of extreme events, along with extreme precipitation depths for 2-50-year return periods, are evaluated under the baseline period (1980-2014) and three future scenarios: SSP1-1.9, SSP2-4.5, and SSP5-8.5 (2021-2080). Daily precipitation and temperature data from the CMIP6 multi-model ensemble are statistically downscaled for 51 stations across Iran using the LARS-WG and transient change factor approach. Extreme precipitation depths increase under SSP1-1.9, whereas the precipitation anomaly depends on location under SSP2-4.5 and SSP5-8.5. The southern coastal and south-eastern regions (remaining stations) will experience more-frequent shorter (less-frequent longer) extreme events. Uncertainty assessment reveals that GCM and downscaling are the main sources of uncertainty in projected precipitation, while the type of scenario significantly contributes to the uncertainty in projected temperature.