Researchers worldwide are looking for new strategies to quantify the human cost of climate change. A recent study estimated that 37% of heat deaths in the past 30 years are attributable to global temperature rise. Another study from Columbia University calculated the "mortality cost of carbon" -- estimating that for every 4,434 metric tons of carbon emissions released into the atmosphere, one person will die of heat illness this century. A third study of global climate-related mortality links 5 million deaths a year to abnormal temperatures.

In contrast, research conducted in the UK found that deaths with climate-related causes dropped. Not only that -- researchers hypothesize that rising temperatures may have actually saved half a million lives since weather-related mortality in England and Wales is typically due to cold temperatures. Still, they urge caution against optimistic interpretations of the study, noting that deaths due to cold weather are easier to count and government programs that subsidize heating and promote flu vaccinations may have also saved lives. Plus, these figures don't represent the full picture -- they do not factor in air pollution, superstorms, fires, or floods.

Why This Matters

These studies, particularly the one out of the UK, demonstrate the challenges in quantifying the toll of climate change, which makes it hard for the public to understand the high stakes of the issue. For this reason, the UK Office for National Statistics plans to release new data on the matter annually, as well as hone their analysis to examine how climate change affects people and places differently. Researchers are seeking a more complete picture as to whether wealthier areas are more resilient to flooding, or less impacted by air pollution. The lead author of this year’s study, Myer Glickman, says answering this could save lives.

The Path Forward

The hope is that data from continued studies can inform life-saving policy interventions, explains Bilal Mateen, the senior manager of digital technology from funding partner Wellcome. By understanding climate change’s varied effects, experts "can begin to tease out what works, what doesn't, and what adaptation and mitigation interventions we should be supporting," he told Wired. According to Mateen, one thing is already clear: the need to support job stability, to address fuel poverty and every other policy that's outside the mandate of the health minister, because we know that those social determinants of health have downstream impact."