Future Climate Change Impacts on Extreme Precipitation: Exposure Risks for Urban Populations and Cropland in North China

Abstract

North China faces increasing risks from extreme precipitation under climate change, yet projections integrating socio-economic dynamics with high-resolution climate models remain limited. Leveraging the latest version of the NEX-GDDP-CMIP6 (NASA Earth Exchange Global Daily Downscaled Projections) from NASA (National Aeronautics and Space Administration) and CMIP6 (Coupled Model Intercomparison Project Phase 6) datasets across SSP1-2.6, SSP2-4.5 and SSP5-8.5 scenarios, this study quantifies future extreme precipitation impacts on urban populations and cropland in two critical periods: 2031–2050 (mid-century) and 2081–2100 (end-century). Through the Multivariable Integrated Evaluation Tool (MVIETool), we demonstrate that NEX-GDDP-CMIP6 reduces regional precipitation biases by 79% compared to CMIP6 (from +133.16 mm/day to −27.00 mm/day), despite persistent uncertainties in extreme intensity indices. Projections reveal a pronounced intensification of extreme precipitation, with R99p (extremely wet day precipitation) increasing by 127%–131% and CDD (consecutive dry days) decreasing by 12%–17% in 2081–2100 under SSP5-8.5, signalling a transition toward wetter conditions. Exposure analyses indicate that 38.24 million citizens (26.32% of the urban population) and 49,900 km² cropland (5.87% of the area) in North China may face record-breaking precipitation events by the end of the century under SSP5-8.5, primarily concentrated in coastal megacities and the North China Plain. These findings underscore the urgency of scenario-specific adaptation strategies, including ‘sponge city’ retrofitting in high-exposure zones and precision agriculture tailored to precipitation regime shifts. Our integrated framework advances regional climate risk assessments by reconciling dynamical downscaling limitations with SSP-driven socio-economic uncertainties.