Two separate studies looking at additional deaths and economic impacts from climate change, and the benefits of reducing greenhouse gas emissions, were in the news this week. One study looked at global impacts, while the other focused on the US.
According to a major new study published by the National Bureau of Economic Research, if planet-heating emissions are not controlled, rising temperatures will cause a death toll large enough to compete with the current number of global deaths from infectious diseases, including HIV/Aids, malaria, dengue and yellow fevers.
This study looked into the global impacts of the climate crisis on loss of human life as well as economic loss. Higher temperatures will be especially devastating for poor people in hotter parts of the world, where some countries will be unable to adapt to unbearable conditions. Those with pre-existing or underlying conditions, which includes poverty, are the most vulnerable. As one co-author noted, “climate change is a public health issue and an equality issue.”
The study considers differing scenarios. If there are continuing high-emissions with little done to curb climate-warming gasses (the world surpasses 3C), researchers estimate an additional 73 deaths per 100,000 people by 2100. The estimate includes deaths directly linked to the heat (heatstroke, e.g.), but also those less obviously linked, such as increases in deadly heart attacks during heatwaves. This toll is comparable to current global deaths from infectious diseases. Poorer societies in the world’s hottest areas would see an additional 200 or more deaths per 100,000 people, while wealthier countries in cooler areas would have fewer deaths, as fewer people would die from the cold.
The researchers projected the economic costs for these deaths to be 3.2% of global economic output by 2100, in their high-emissions scenario, with each ton of carbon dioxide emissions costing $36.60 in damage. The study’s moderate scenario, where emissions are rapidly cut, would bring less than a third of the deaths associated with the high-emissions scenario, and significantly lower economic costs.
The second study, from Duke University, found that the US could avoid 4.5 million premature deaths (estimated value over $37 trillion), if global temperatures are kept from increasing more than 2 degree Celsius.
Drew Shindell, the Duke professor who conducted the study with NASA researchers, told lawmakers this week at a House Oversight Committee hearing that limiting climate change could also prevent around 3.5 million US hospitalizations and emergency room visits (valued at over $37 billion) and 300 million lost workdays (valued at over $75 billion). This yields, on average, “over $700 billion per year in benefits to the U.S. from improved health and labor alone, far more than the cost of the energy transition.”
The study looked at the US benefits of keeping to the goal of the Paris Climate Accord, which the US cannot officially exit until Nov. 4, 2020. Moving away from fossil fuels, Shindell noted, would reduce the impacts of climate change and also bring health benefits from reduced air pollution. Further, benefits would be noticeable in the relatively short term. “[A]ir pollution responds immediately to emissions reductions,” he said, and within 20 years, “[r]oughly 1.4 million lives could be saved.”