"The lowest-cost approach only looks at how much it will cost to transform the energy sector. It ignores the human cost of more than 150 million lost lives, or the fact that slashing emissions in the near term will reduce long-term climate risk and avoid the need to rely on future carbon dioxide removal," said Drew Shindell, Professor of Earth Sciences at Duke's Nicholas School of the Environment. "That's a very risky strategy, like buying something on credit and assuming you'll someday have a big enough income to pay it all back."
The Duke researchers partnered with Columbia University's Center for Climate Systems Research and NASA's Goddard Institute for Space Studies to conduct the analysis, which looked at 154 of the world’s biggest cities.
Based on their combined knowledge of air pollution, the team modeled three separate scenarios through computer simulation; accelerated reductions in carbon emissions over 100 years, slightly higher emissions that current day, and a reduction that would limit global warming to only 1.5 degrees in the next century.
Drawing on epidemiological data from major urban hubs worldwide, and health statistics related to air pollution, the team was able to identify significant danger areas, and cities that had the potential to save the most lives by committing to cleaner living.
The study suggested that the largest beneficiary of accelerated emission cuts would be Delhi and Kolkata with both saving over 4 millions lives each in the next 100 years. The greatest number of prevented premature deaths would reportedly occur in Asia and Africa, with thirteen cities saving over 1 million people.
Other world hubs, such as Moscow, Mexico City, Sao Paolo, Los Angeles, Puebla and New York were identified by the scientists as having the potential to save between 320,000 and 120,000 premature deaths as a direct result of cleaner air.
"Since air pollution is something we understand very well and have extensive historical data on, we can say with relatively high certainty how many people will die in a given city under each scenario," Shindell said. "Hopefully, this information will help policymakers and the public grasp the benefits of accelerating carbon reductions in the near term, in a way that really hits home."