According to the most recent study on the human cost of climate change, more than one-third of the world's heat deaths each year are directly caused by global warming.
But, according to scientists, that is only a fraction of the overall toll of climate change; even more people
die from other extreme weather
events exacerbated by global warming, such as storms, flooding, and drought
, and the number of heat-related deaths will rise exponentially as temperatures rise.
According to a study published Monday in the journal Nature Climate Change
, dozens of researchers examined heat deaths in 732 cities worldwide from 1991 to 2018, and found that 37% were caused by higher temperatures caused by human-caused warming.
According to the study's lead author, this equates to approximately 9,700 people per year from just those cities, but it is much higher globally.
“These are heat-related deaths that can be avoided, and it is something we directly cause,” said Ana Vicedo-Cabrera
, an epidemiologist at the University of Bern’s Institute of Social and Preventive Medicine.
Vicedo-Cabrera mentioned southern Europe and southern Asia as other hotspots for climate change-related heat deaths.
According to researchers, Sao Paulo, Brazil
, has the highest number of climate-related heat deaths, with an average of 239 per year.
According to the study, climate change is responsible for approximately 35% of heat deaths in the United States
, amounting to more than 1,100 deaths per year in approximately 200 U.S. cities, led by 141 in New York
. Honolulu had the highest percentage of heat deaths attributable to climate change, accounting for 82%.
Scientists used decades of mortality data from the 732 cities to plot curves detailing how each city's death rate changes with temperature and how heat-death curves differ from city to city. Some cities adapt to heat better than others due to air conditioning, cultural factors, and environmental conditions, according to Vicedo-Cabrera.
The researchers then compared observed temperatures to 10 computer models simulating a world without climate change, with the difference being the warming caused by humans. By applying that scientifically accepted technique to the 732 cities' individualized heat-death curves, the scientists calculated extra heat deaths from climate change.
“People continue to ask for proof that climate change is already affecting our health
, and this attribution study directly answers that question using cutting-edge epidemiological methods, and the amount of data the authors have amassed for analysis is impressive,” said Dr. Jonathan Patz, director of the University of Wisconsin
’s Global Health Institute.
Patz, who was not involved in the study, said it was one of the first to detail climate change-related heat deaths that occurred now rather than in the future.
The Associated Press
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