The case for climate solutions has long been hindered because of the decades it will take for investments made today to yield benefits in the form of less extreme weather impacts. Carbon dioxide pollution remains in the atmosphere for upwards of a millennium, and so efforts to curb carbon emissions will only slowly bend the global warming curve. Clean technologies deployed today will yield significant changes in extreme weather only toward the middle of the century.
Compelling people to support climate solutions thus usually requires appealing to their better natures; to invest in protecting the future quality of life of today’s children. People often have difficulty making decisions based on such long-term considerations.
But as a new study in the Proceedings of the National Academy of Sciences (PNAS) concludes, curbing climate change does yield immediate benefits in the form of cleaner air resulting in healthier and longer lives. The paper was authored by 11 scientists from Duke and Columbia Universities and the NASA Goddard Institute for Space Studies (GISS), including lead author Drew Shindell, who has published over 250 peer-reviewed climate studies over the past 25 years, and NASA GISS Director Gavin Schmidt.
The study estimates that Americans would value the benefits of longer lives associated with cleaner air at $700 billion per year over the next two decades – a number far higher than the costs of climate solutions.
Valuing longer and healthier lives from cleaner air
In addition to pumping greenhouse gases into the atmosphere, burning fossil fuels also releases other air pollutants that create higher levels of ozone and easily respirable fine particulate matter like PM2.5. Ozone can aggravate lung diseases like asthma and emphysema, while PM2.5 can cause premature death in people with heart problems or lung disease and can also aggravate asthma. A 2018 study, also published in PNAS, has found that outdoor PM2.5 air pollution is considerably more harmful to human health than previously estimated.
Those results were incorporated into this new research, which estimates that in 2020, PM2.5 and ozone pollution caused 191,000 and 57,000 premature deaths in the U.S., respectively, compared to 17,000 heat-related deaths. Were the U.S. to follow a pathway to meet the 2015 Paris climate agreement target of limiting global warming to 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial temperatures, many of these premature deaths would be avoided (19% of PM2.5 and 57% of ozone deaths over the next two decades; 31% and 77% through 2070, respectively).
All told, close to 1.4 million premature American deaths would be avoided through 2040 and 4.5 million through 2070, compared to a business-as-usual pathway. And those longer lives would also be healthieras a result of people’s breathing cleaner air.
Proponents of the fossil fuel status quo might ask: Are those healthier, longer lives worth the cost of transitioning to a clean energy economy? Given that numerous studies, including a new working paper from Oxford, have concluded that faster transitions to clean energy will also be cheaper in the long run, it’s difficult to make a case to the contrary.
But how much do we value longer, healthier lives? This is a subjective moral question that scientists approach using a concept known as the “value of a statistical life,” which can be estimated, for example, by asking people how much they would be willing to pay to reduce their risk of death in a given year. Based on this approach, Americans would value their reduced health risks associated with decreasing air pollution at roughly $14 trillion over the next 20 years, or $700 billion per year. The new PNAS study thus concludes that for climate solutions, “benefits greatly outweigh costs immediately with a benefit/cost ratio of 5-25 in 2030 under a 2°C scenario.”
The study authors have also created a website that provides the state-by-state health benefits. For example, meeting the U.S. share of the Paris targets would yield cleaner air that would prevent 8,000 premature deaths in West Virginia over the next 20 years, valued at over $80 billion.
Other health and climate benefits
In addition to a cumulative value of $54 trillion through 2070 to the U.S. from avoiding 4.5 million premature deaths, the study estimates that the cleaner air resulting from meeting the Paris targets would prevent “about 1.4 million hospitalizations and emergency room visits, approximately 300 million lost workdays, about 1.7 million incidences of dementia, and about 440 million tons of crop losses.” Those figures amount to savings of “$111 billion for avoided dementia costs, $53 billion for avoided labor losses, $72 billion for avoided crop losses, and $10 billion for avoided hospitalizations and ER visits.”
After 2060, once climate actions may have significantly bent the global warming curve and air pollution has largely been phased out, avoided heat-related deaths could become the biggest value associated with curbing climate change. The study does not directly incorporate the benefits from lessened extreme weather disasters other than heat deaths but uses the “social cost of carbon” to estimate that avoided climate damages amount to $300 billion per year in 2050 and $1.4 trillion per year in 2100.
The authors conclude:
“We find that the climate benefits (i.e. associated with heat) alone are less than mitigation costs over the next two decades, reaching parity with mitigation costs around 2040–2055. In the longer term, those benefits clearly outweigh costs, in line with much documentation that the costs of inaction would eventually be higher than the costs of action.”
In short, preserving a stable, livable climate for future generations should provide sufficient economic and moral justification for climate solutions today. But in the near-term, climate solutions will also result in immediate benefits from cleaner air, better health, and longer lives, valued by Americans at $700 billion dollars per year.
The case for phasing out fossil fuels is even more compelling in countries like China and India where air pollution is a more severe problem than in the U.S. Another new study published in Nature Scientific Reports found that meeting the Paris targets could prevent 4 million heat-related deaths globally over the rest of the century compared to a worst case global warming scenario, especially in hot (and often poorer) countries near the equator in Africa, the Middle East, and Southern Asia, including over 1 million saved lives in India alone.
But another new study published in Nature found that people in many developing countries will remain too poor for most of the century to take adaptive measures like buying air conditioning units or even having access to the electricity to power them. As study co-author Solomon Hsiang of UC Berkeley put it, “richer populations can protect themselves from the impacts of warming, but the global poor don’t have this luxury.” Only 5% of homes in India currently have air conditioning, for example. The Nature Scientific Reports study found that mortality resulting from extreme heat could be considerably worse in high-warming scenarios if poorer countries are unable to implement such adaptive measures.
To summarize: Clean energy investments more than pay for themselves over time; they yield tremendous long-term benefits via lessened extreme weather disasters and heat-related deaths, especially in more vulnerable developing countries; and the resulting clean air also yields valuable immediate benefits in the form of longer, healthier lives valued by Americans at close to a trillion dollars per year. Considering these analyses, it seems the case for investing in the deployment of clean technologies could hardly be more compelling.