Climate change might reduce life expectancy by half a year, demonstrating another grave consequence of human-caused global warming.
Temperature and rainfall-two unmistakable signs of climate change-cause a wide range of public health concerns, from the acute and direct to the indirect but equally catastrophic.
Temperature and Rainfall
While these effects are visible and extensively documented, current research does not show a direct link between climate change and life expectancy.
While extensive research has documented a slew of negative health effects associated with climate change-including potentially lethal heat, the risk of new deadly pandemics, an increase in extreme weather events and natural disasters, and risks for those with breathing and mental health issues-Dr. Amit Roy from Shahjalal University of Science and Technology and The New School for Social Research in the United States stated that no direct link between the phenomenon and life expectancy has yet been established.
To elucidate this relationship, the study in the open-access journal PLOS Climate reviewed average temperature, rainfall, and life expectancy data from 191 nations from 1940 to 2020, using GDP per capita to compensate for dramatic changes between countries.
In addition to analyzing the individual effects of temperature and rainfall, the researchers created a first-of-its-kind composite climate change index, which combines the two variables to assess the overall severity of climate change.
According to the findings, a 1°C increase in global temperature is related to a 0.44-year drop in average human life expectancy, or nearly six months and one week.
A 10-point increase in the composite climate change index-which includes both temperature and rainfall-is anticipated to reduce average life expectancy by six months.
Women and individuals from developing countries are disproportionately affected.
Read Also: Living in Climate Change 'Danger Zones' Can Expose Humans to Deadly, Extreme Weather Events
Reducing Greenhouse Gas Emission
Beyond the findings of this study, Roy hopes that the composite climate change index will standardize the global conversation about climate change, become a usable metric for the nonscientific public, and encourage collaboration and even friendly competition among countries in combating the effects of climate change.
Roy emphasizes the significance of reducing greenhouse gas emissions and adjusting to a changing climate.
To supplement this large-scale approach, the author advises focused future studies that include specific severe weather events (e.g., wildfires, tsunamis, and floods), whose impacts cannot be adequately captured by examining temperature and rainfall alone.
"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, as revealed by this study, emphasizing that mitigation efforts to reduce greenhouse gas emissions and proactive initiatives are essential to safeguard life expectancy and protect the health of populations worldwide," he added.
Shifting to renewable energy, placing a price on carbon, and phasing out coal are all key steps toward lowering greenhouse gas emissions. Ultimately, larger emission reduction targets are required to ensure long-term human and environmental health.
During COP26, the European Union and the United States announced the Global Methane Pledge, which calls on over 100 countries to reduce 30% of methane emissions in the fuel, agriculture, and waste sectors by 2030.
"We need to implement strong policies that back the raised ambitions. We cannot continue down the same path and expect better results. Action is needed now," says Mark Radka, Chief of the UN Environment Programme's (UNEP) Energy and Climate Branch.
Related Article: Climate Change: The Negative Effects on Human Health