WASHINGTON (AP) — A recent study has concluded that approximately 1,500 deaths in last week’s European heat wave were directly linked to human-caused climate change. This groundbreaking research is the first of its kind to establish a direct correlation between the burning of fossil fuels and mortality rates during extreme weather events. Friederike Otto, a co-author and climate scientist at Imperial College London, emphasized that these individuals would not have died if it weren't for the climate impacts stemming from the combustion of oil, coal, and natural gas over the past century.
Scientists from Imperial College and the London School of Hygiene and Tropical Medicine conducted a rapid study that estimated around 2,300 total heat-related deaths across 12 cities, with nearly two-thirds attributed to the added heat from climate change. Previous studies typically focused on the meteorological impacts of climate change, such as heat and flooding, but this research goes further by directly linking fossil fuel consumption to human mortality.
Gary Konstantinoudis, a biostatistician at Imperial College and co-author of the study, pointed out that heat waves are often overlooked as silent killers. This is largely because medical professionals and governmental institutions frequently attribute deaths during heat waves to underlying health issues like heart or lung problems, rather than recognizing heat as a direct cause of death.
The study revealed that more than 1,100 of the 1,500 heat-related deaths were among individuals aged 75 and older. Ben Clarke, the lead author of the study, noted that while summer temperatures can be naturally warm, climate change has increased these temperatures by several degrees. This rise in temperature pushes vulnerable populations into more dangerous conditions.
Researchers focused on the period from June 23 to July 2, examining cities including London, Paris, Frankfurt, Budapest, Zagreb, Athens, Barcelona, Madrid, Lisbon, Rome, Milan, and Sassari. They found that climate change amplified the natural heat by 2 to 4 degrees Celsius (3.6 to 7.2 degrees Fahrenheit) in most cities, with London experiencing the most significant increase of nearly 4 degrees (7.2 degrees Fahrenheit). Conversely, Lisbon saw only about a degree increase due to the moderating effect of the Atlantic Ocean.
The study noted that the highest number of climate change-related deaths occurred in Milan, Barcelona, and Paris, whereas Sassari, Frankfurt, and Lisbon experienced the least. The total of 1,500 deaths is an average estimate, with overall climate-related death figures ranging from approximately 1,250 to 1,700.
This study is not yet peer-reviewed but is an extension of ongoing research tracking climate change’s impact on extreme weather events. By comparing actual temperature readings from last week to computer simulations of a world without climate-change-inducing greenhouse gases, the researchers could assess the additional health risks posed by rising temperatures.
The methodology involved established formulas that account for excess deaths resulting from abnormal weather patterns and various demographic factors, allowing researchers to isolate temperature as a causal factor. Health researchers also considered variables such as chronic diseases and lifestyle habits, ensuring that comparisons made were between similar groups of individuals except for exposure to heat.
Previous studies from 2021 linked heat-related deaths to human-induced climate change and carbon emissions but did not specifically address single events like this recent heat wave. A 2023 study published in Nature Medicine indicated that in Europe, for every degree Celsius increase in temperature, there are an additional estimated 18,547 summer heat-related deaths since 2015.
Experts like Dr. Jonathan Patz, who leads the Center for Health, Energy, and Environmental Research at the University of Wisconsin, have commended research like this for clarifying the health consequences of continuing fossil fuel dependency. Dr. Courtney Howard, an emergency room physician and chair of the Global Climate and Health Alliance, highlighted the importance of reducing fossil fuel use for public health benefits.
