Intensifying Sub‐Daily Rainfall Extremes in Tropical Cities: Projections From Downscaled Baselines in a Warming Climate

作者：Jovan Blagojević, Nadav Peleg, Andreas F. Prein, Francesco Marra, Athanasios Paschalis, Peter Molnar · 发表于：Repository for Publications and Research Data (ETH Zurich) · 年份：2026 · DOI：10.3929/ethz-c-000803478 · 研究领域：Climate variability and models、Urban Heat Island Mitigation、Tropical and Extratropical Cyclones Research

Tropical cities are frequently exposed to short and intense rainfall that poses a significant flood risk to rapidly growing populations, making it essential to predict how these extremes will evolve under climate change. However, local projections remain limited by the lack of high‐resolution climate simulations and long‐term meteorological records. To address this, we present a globally scalable framework that downscales gridded daily rainfall data to hourly resolution using a stochastic disaggregation model. The model is calibrated using satellite‐derived hourly rainfall statistics, and rainfall intensity‐temperature scaling is applied using General Circulation Model‐projected dew point temperatures, eliminating the reliance on local hourly records. By linking dew point temperature‐rainfall relationships to projected changes from climate models, we generate future intensity‐duration‐frequency curves across 20 tropical and subtropical cities. Results show hourly rainfall intensities increase by 10%–17% by 2080–2100 relative to 1995–2014 under SSP2‐4.5 and under the assumption of Clausius‐Clapeyron scaling, with rare high‐impact events becoming up to six times more frequent under SSP5‐8.5. Temperature‐rainfall scaling emerges as the dominant source of uncertainty, surpassing climate model and emission uncertainty. We further show that using only mean temperature shifts rather than changes in the entire temperature distribution may significantly underestimate rainfall intensif...