Climate change could cut life expectancy by half a year, according to research published Thursday, illustrating another ominous consequence of human-driven global heating after scientists confirmed 2023 as the hottest year on record.
Changes in temperature and rainfall caused by climate change could shave six months off the average human lifespan, researcher Amit Roy said in a paper published in the journal PLOS Climate.
PLOS Climate informed Forbes it is investigating data used in the study after questions were raised about its reliability after publication and Roy did not immediately respond to request for comment on the matter.
Roy, a researcher at The New School for Social Research and Bangladesh’s Shahjalal University of Science and Technology, came to the conclusion after analyzing life expectancy data from 191 countries between 1940 and 2020.
An annual temperature increase of 1 degree Celsius on its own would cut average human life expectancy by around five and a half months once other factors affecting lifespan like GDP are accounted for, Roy said.
Changes in rainfall—which is disrupted in a multitude of health-affecting ways by climate change—also have an impact on life expectancy, the data showed.
Considered in isolation without temperature changes, an increase or decrease in rainfall could be both beneficial or detrimental depending on circumstances—for example, in an area already experiencing heavy rainfall or an area experiencing drought.
However, when considered alongside temperature changes, Roy—who developed a new composite index to consider the combined impact of the two features on life expectancy—found a more negative outcome, with a 10-point change on the index combining the two features leading to a six month drop on the average life expectancy.
Women and those in developing nations are disproportionately affected by the life expectancy hit, Roy said.
Scientists have confirmed 2023 as the hottest year on record and experts warn 2024 could be hotter still.
Experts overwhelmingly believe that human activity is driving significant and rapid climate change the likes of which our planet has never experienced and warn that even with drastic action to mitigate damage, a great deal of hardship from this is going to be in store for coming decades.
While variations in climate are a normal and expected part of the planetary ecosystem, emissions of greenhouse gasses like carbon dioxide and methane have disrupted natural cycles and help lock heat inside the planetary system.
These temperature increases have disrupted climatic patterns and features like rainfall, which can both decrease and cause problems in the form of phenomena like drought and increase and cause issues like flooding in wetter areas.
Without drastic and swift action to cut emissions, scientists warn we will cross planetary tipping points from which there may not be a return and extreme weather like storms, droughts and freezes are expected to increase in both frequency and severity.
While abundant research has documented a slew of negative health effects linked to climate change—including potentially lethal heat, the risk of new deadly pandemics, an uptick in extreme weather events and natural disasters and risks for those with breathing and mental health problems—Roy said none had yet established a direct link between the phenomenon and life expectancy.
“The global threat posed by climate change to the well-being of billions underscores the urgent need to address it as a public health crisis,” Roy said, adding: “mitigation efforts to reduce greenhouse gas emissions and proactive initiatives are essential to safeguard life expectancy and protect the health of populations worldwide.”
