New research published in Nature Climate Change analyzes the economic impacts of anthropogenic aerosol emissions. Aerosols emitted by humans interact with the clouds in the atmosphere and reflect sunlight, resulting in a temporary cooling effect. Researchers from Carnegie wanted to figure out the effect that such cooling has on different regions of the world, from an economic perspective.
"Estimates indicate that aerosol pollution emitted by humans is offsetting about 0.7 degrees Celsius, or about 1.3 degrees Fahrenheit, of the warming due to greenhouse gas emissions," said lead author Yixuan Zheng. "This translates to a 40-year delay in the effects of climate change. Without cooling caused by aerosol emissions, we would have achieved 2010-level global mean temperatures in 1970."
The authors of the paper include an important disclaimer in their research, cautioning that although there are indeed positive effects of aerosols, they are by no means recommending the emission of them due to the threats they pose to human health.
"We need to understand how human activities affect our planet so we can make informed decisions that can protect the environment while giving everyone a high quality of life," researcher Ken Caldeira concluded. "Aerosol pollution might appear to have some upsides, but at the end of the day their profound harm far outweighs their meager benefits."
In conducting their investigations, the researchers found that the cooling effect of aerosols benefitted the economies of tropical countries and harmed the economies of high latitude countries. These findings are opposite to the effects of global warming, which are generally benefitting higher latitudes’ economies and harming tropical climates’ economies.
"Although aerosols have many negative impacts, our simulations demonstrated that aerosol-induced cooling, in particular, could actually diminish global economic inequality," said researcher Geeta Persad. Research Steven Davis added, "However, when you look at the whole world at once, rather than region by region, the net economic effect of this cooling is likely to be small due to these effects between latitudes.”