Increasing risk of compound heatwave-pluvial hazards in highly populated regions

Compound heatwave-pluvial events (CHPEs) can cause severe socio-economic damage and are difficult to predict because of their complex transition processes. Moreover, their spatial patterns and impacts on socio-economic systems remain poorly understood. Using an extensive set of atmospheric reanalysis data and model simulations, we observed a significant global increase in the frequency and duration of CHPEs from 1980 to 2021, with hotspots in Central Europe, East Asia, the Tibetan Plateau, Southern Africa, the Amazon Basin, and North America. Low-income countries are projected to experience a significantly higher population (+42.2%) and GDP exposure (+46.4%) to CHPEs than high-income countries under the SSP585. These findings emphasize the ongoing disparities in exposure under future socio-economic scenarios, highlighting the urgent need to develop equitable and just mitigation and adaptation strategies, particularly in less-developed regions.