Climate change could reduce average life expectancy by six months, study finds

The cost of climate change could reduce the average human lifespan by six months, according to a study published January 18, 2024 in the open access journal. Climate PLOS by Amit Roy from Shahjalal University of Science and Technology and New School for Social Research, USA

Temperature and precipitation – two telltale signals of climate change – cause a myriad of public health problems, from the most acute and direct (for example, natural disasters like floods and heat waves) to the indirect but all also devastating (e.g. respiratory and mental illnesses). Although such impacts are observable and well documented, existing research has not established a direct link between climate change and life expectancy.

To clarify this relationship, the author evaluated average temperature, precipitation, and life expectancy data for 191 countries from 1940 to 2020, using GDP per capita to control for drastic differences between countries.

In addition to measuring the isolated impacts of temperature and precipitation, the author designed a first-of-its-kind composite climate change index that combines the two variables to assess the overall severity of climate change.

The results indicate that, in isolation, an increase in global temperature of 1°C is associated with an average decrease in human life expectancy of about 0.44 years, or about six months and one week. A 10-point increase in the composite climate change index – which takes into account both temperature and precipitation – is expected to reduce average life expectancy by six months. Women and individuals in developing countries are disproportionately affected.

Beyond the results of this study, Dr. Roy hopes that the composite climate change index will normalize the global debate on climate change; become a usable measure for the non-scientific public; and encourage collaboration, even friendly competition, between countries to combat the impacts of climate change.

Mitigation of greenhouse gas emissions and adaptation to a changing environment are of particular importance, says the author.

To complement this large-scale approach, the author suggests future localized studies that consider specific severe weather events (e.g. wildfires, tsunamis, and floods), whose impacts cannot be fully captured by the sole analysis of temperature and precipitation.

Dr Roy adds: “The global threat that climate change poses to the well-being of billions of people highlights the urgent need to address it as a public health crisis, as this study reveals, highlighting that efforts to Mitigation aimed at reducing greenhouse gas emissions and proactive measures Initiatives are essential to preserve life expectancy and protect the health of populations around the world.