The first global heat-related death mapping study found more than 153,000 heat-related deaths per season worldwide from 1990 to 2019, with Asia worst-hit.

The Monash-led study, the first to map global heat-related deaths over three decades from 1990 to 2019, found that an extra 153,000 deaths during the hot season were heat-related, with almost half of those deaths in Asia.

Compared with 1850–1990, global surface temperature increased by 1.14°C in 2013–2022 and is expected to increase by a further 0.41–3.41°C by 2081–2100. As the impact of climate change increases, not only the frequency but also the severity and intensity of heat waves increases.

In a study published today PLoS Medicine The team, led by Monash University professor Yuming Guo, examined daily mortality and temperature data from 750 locations in 43 countries or territories.

The study, conducted in collaboration with Shandong University in China, the London School of Hygiene and Tropical Medicine in the UK, and universities/research institutes in other countries, found that between 1990 and 2019, heat waves led to an increase in the deaths of 236 people. . for a population of ten million during the warm season. The regions with the highest number of heat-related deaths were:

• Southern and Eastern Europe
• regions with polar and high mountain climates
• places where residents have high incomes

Tropical or low-income regions experienced the largest declines in the burden of heat-related deaths from 1990 to 2019. According to Professor Guo, studies on increased mortality rates associated with exposure to heatwaves have been examined and he said “the evidence mostly comes from limited places”.

“Our findings that heatwaves are associated with a significant spatio-temporally varying mortality burden worldwide over the past 30 years highlight the need for local adaptation planning and risk management at all levels of government.”

According to the study authors, heat waves cause an increased risk of death due to tremendous thermal stress on the human body and cause multiple organ dysfunction as well as heat exhaustion, heat cramps and heat stroke. Heat stress can also worsen existing chronic diseases, leading to premature death, mental disorders and other consequences.