Global Warming Enhances Tropical Cyclone-Induced Extreme Precipitation in the Arabian Sea: Insights From Convection-Permitting Model Experiments

Abstract

The frequency and intensity of extreme weather events have risen with climate change, affecting multiple sectors worldwide. This study examines the influence of anthropogenic warming on intense tropical cyclones (TCs) over the Arabian Sea using convection-permitting simulations with the Weather Research and Forecasting (WRF) model. In particular, we provide the first quantitative assessment of the impact of anthropogenic forcing on recently observed TC-induced extreme rainfall. Human-induced changes were assessed through two experiments: all forcings (ALL) and natural forcings only (NAT). Anthropogenic warming "delta" patterns of sea surface temperature, relative humidity, and air temperature were derived from CMIP6 models and applied in WRF under a pseudo-global warming framework. Three major TCs-Ockhi (2017), Kyarr (2019), and Maha (2019)-were simulated, and the model reproduced their tracks, intensities, and rainfall with high fidelity. Comparison of ALL and NAT runs shows a clear anthropogenic signal: TC-induced total and extreme rainfall both increases, linked to stronger vertical motion and greater moisture availability that enhance latent heat release and deep convection. Furthermore, there is a statistically significant expansion in the area experiencing extreme rainfall by similar to 16%-34%, and an enhanced intensity of extreme rainfall by similar to 4%-12% under anthropogenic warming. Additional differences in vertical thermal profiles and warm-core structures further highlight the impact of human-induced climate change on TC dynamics.