If—or, depending on your outlook, when—the world ever endures a nuclear war, scientists have an inkling of what the environmental effects could be thanks to devastating Canadian wildfires from 2017.
According to a new Rutgers University study published Thursday in Science Magazine, wildfires in British Columbia in August 2017 expelled so much smoke into the atmosphere that the pyrocumulonimbus (pyroCb) cloud sat in the upper atmosphere for eight months. Soot in the cloud was heated by solar radiation and lifted the cloud higher into the sky, combining with the dry air in the north to keep the cloud aloft until the next spring.
“This process of injecting soot into the stratosphere and seeing it extend its lifetime by self-lofting, was previously modeled as a consequence of nuclear winter in the case of an all-out war between the United States and Russia, in which smoke from burning cities would change the global climate,” study co-author and professor in the Department of Environmental Sciences at Rutgers University–New Brunswick Alan Robock said in a press release announcing the findings.
Not that the world’s two most powerful militaries need to be involved—a relatively low-level nuclear war between India and Pakistan, for example, could “cause climate change unprecedented in recorded human history and global food crises,” said Robock.
The study used the smoke from the wildfires as a model, but the scale of smoke in the atmosphere from an all out nuclear war would be orders of magnitude greater.