An energetics tale of the 2022 mega-heatwave over central-eastern China

Abstract

It remains a major challenge to attribute heatwave’s lifecycle characteristics quantitatively to interwoven atmospheric and surface actions. By constructing a process-resolving, energetics-based attribution framework (PREAF), here we quantitatively delineate the lifecycle of the unprecedented 2022 mega-heatwave over central-eastern China from a local energetics perspective. It is found that the cloudlessness induced radiative heating and atmospheric dynamics dominate the total energy buildup during the developing stage, while the land-atmosphere coupling and atmospheric horizontal advection act most effectively to sustain and terminate the heatwave, respectively. A reduction in anthropogenic aerosols provides a persistent positive contribution during the event, suggesting that pollution mitigation measures may actually increase the amplitudes of future heatwaves. With the PREAF, initial efforts are made to unravel culprits in a model’s sub-seasonal prediction of this mega-heatwave, demonstrating the framework’s potential for efficiently detecting the origins of climate extremes and quantitatively assessing the impacts of mitigation policies for sustainable development.