According to a world-first international study led by Australia’s Monash University, more than five million deaths a year can be attributed to climate change.
Scientists at Monash analysed temperature and mortality data from dozens of countries across the world over the first 20 years of this century.
While fewer people are dying from cold weather, deaths from abnormal warmer conditions are causing concern.
The study found deaths related to hot temperatures increased in all regions from 2000 to 2019. This indicates that global warming due to climate change will make this mortality figure worse in the future.
It is the first study to definitively link above and below optimal temperatures to annual increases in mortality.
The study found 9.43 per cent of global deaths could be attributed to cold and hot temperatures. This equates to 74 excess deaths for every 100,000 people.
Importantly, cold-related death decreased 0.51 percent from 2000 to 2019, while heat-related death increased 0.21 per cent. This led to a reduction in net mortality due to cold and hot temperatures.
Professor Yuming Guo, from the Monash University School of Public Health and Preventive Medicine, said this shows global warming may “slightly reduce the number of temperature-related deaths, largely because of the lessening in cold-related mortality.”
“However, in the long-term, climate change is expected to increase the deaths burden because hot-related mortality would be continuing to increase,” Guo concluded.
In other words, eventually the growing number of deaths attributable to excess heat would surpass those saved.
According to NASA, 19 of the world’s hottest years since records began have happened in the past 20 years. Every year in the past decade has been hotter than the 20th century’s record-holder, 1998. Global mean temperatures are increasing about 0.26C a decade.
“As each new year is added to the historical record, it becomes one of the top 10 warmest on record at that time, but it is ultimately replaced as the ‘top ten’ window shifts forward in time,” according to the US National Oceanic and Atmospheric Administration.