Assessing High-Resolution Precipitation Extremes in Central Asia: Evaluation and Future Projections

Abstract

The impact of anthropogenic climate change on ecosystem sustainability in Central Asia's semi-arid and arid regions relies significantly on changes in extreme precipitation events. Accurate forecasting of these events is crucial for tailored adaptation strategies. This study examines projected changes in mean and extreme precipitation indices in Central Asia from 1985 to 2100. Utilizing ERA5, CPC, and high-resolution NEX-GDDP data from CMIP6 models, four SSP scenarios were assessed over three-time frames. The CMIP6 Multi-Model Ensemble (MME) shows coherence in simulating mean annual precipitation, albeit with weaker performance in mountainous regions. It consistently underestimates PD10MM and SDII while overestimating CDD in high-altitude areas with more precipitation. Projections indicate a potential up to 50% increase in mean annual precipitation across most of Central Asia, notably amplifying from the mid-future onward. Precipitation extremes like SDII, RX1DAY, and days with over 10 mm of precipitation are increasing spatiotemporally. Conversely, CDD may decrease in eastern Central Asia but increase in the west by the century's end. These shifts signify a rising wetness trend in Central Asia under warming conditions, resulting in more frequent heavy precipitation events and fewer dry spells, especially in high-emission scenarios.