Global compound health risk assessment of extreme heat and ozone pollution

Summary: Global climate change has exacerbated the frequency and intensity of extreme heat and ozone pollution, posing a serious threat to human health. Extreme heat is one of the deadliest meteorological hazards. High temperature conditions accelerate atmospheric photochemical reactions, leading to an increase in ozone concentrations, which in turn creates a compounded exposure risk of extreme heat and ozone pollution. Studies have shown that this compound exposure is a more serious threat to health than a single exposure. It may result in an increase in excess mortality of up to 1.8 to 3.5 times. Global compounded exposure events are expected to increase significantly under future high-emission scenarios. However, systematic studies of this compound health risk on a global scale still lack a unified assessment framework to quantify the health impacts accurately. Therefore, this study aims to accurately predict the global compound health risk pattern of extreme heat and ozone pollution, and assess its health impacts on different populations. It provides support for the synergistic management of climate change and air pollution.