Increases in extreme precipitation expected in Northeast China under continued global warming

Changes in extreme precipitation in Northeast China (NEC), a climate-sensitive region, remain unclear with respect to future warming due to regionally unique geographic factors. This study examines how regional extreme precipitation may adapt to future climate change. Using statistical downscaling and the CMIP6 multi-model ensemble, we investigate the possible changes in future extreme precipitation for NEC under different warming scenarios and the influencing factors. The results indicate that extreme precipitation events, under different definitions, exhibit a gradual enhancement trend and are more pronounced for the more extreme precipitation definitions. However, in projections of the late twenty-first century, under the Scenario Model Intercomparison Project (2015-2100) Shared Socioeconomic Path (SSP)2-4.5 scenario, the growth of extreme precipitation events plateaued as warming slowed. The response of extreme precipitation to temperature changes under SSP2-4.5 (SSP5-8.5) was approximately linear, with average response rates of 7.29%/degrees C (6.71%/degrees C) and 16.84%/degrees C (17.33%/degrees C) for number of days with daily precipitation exceeding 20 mm and annual total precipitation of days exceeding the 99th percentile threshold, respectively. The distribution of these indices was more concentrated under SSP5-8.5 scenario. Variations in the spatial distribution of extreme precipitation were significantly correlated with vertical velocity at 500 hPa and were influenced by moisture availability. The predicted increase in extreme precipitation was greater in humid and mountainous regions and precipitation changes were most pronounced at higher latitudes. Our results suggest that future temperatures may increase the risk of extreme precipitation in NEC, posing a challenge for adaptation to changes in precipitation extremes.