Climate scientists warn that 55 trillion kilograms of carbon could be released into the atmosphere from Earth's soil by mid-century.
Fosheim Peninsula, Canada. Image: Flickr/UBC Micrometeorology
The term "snowball effect" is an unfortunate way to describe climate change, but a new study is predicting just that.
Climate scientists warn that by 2050, an astonishing 55 trillion kilograms of carbon could be released into the atmosphere from the soil. To put things in perspective, that's the emissions equivalent of adding another United States to the planet. And, like a rapidly tumbling snowball, more emissions mean more warming, and more warming means… well, you get it.
Of course, this nightmare scenario hinges on our inability to curb carbon emissions—a fate that's become significantly more realistic with Donald Trump, a vocal climate change denier and coal aficionado, about to enter the White House. Our failure to meet the goals mandated by the Paris Agreement would result in "about 17 percent more than the projected emissions due to human-related activities during that period," Tom Crowther, the study's lead author and a researcher at the Netherlands Institute of Ecology, said in a statement.
The new study, which was published in Nature this week, presents findings from a global survey of soil data collected over the past 20 years. Scientists have been researching terrestrial carbon for decades, not only over its potential to emit greenhouse gases, but also for its ability to store them. However, Crowther claims this is the first time a worldwide perspective of soil emissions has ever been presented.
Unlike other surveys, Crowther said, this one considered carbon losses from some of the coldest places on Earth.
In the Arctic, for example, enormous caches of carbon have accumulated in the soil over thousands of years. Because of freezing temperatures, the microbes that normally stimulate the release of carbon through decomposition are less active in these regions. But as temperatures continue to rise, as they've done precipitously this year, these microbes could become more lively, accelerating the rate at which carbon is emitted into the atmosphere.
"Carbon stores are greatest in places like the Arctic and the sub-Arctic, where the soil is cold and often frozen," Crowther added. "The scary thing is, these cold regions are the places that are expected to warm the most under climate change."
The 55 trillion kilograms of emissions would come in the form of carbon dioxide (CO2) and methane, according to the study. Methane, which possesses up to 25 times the warming power of CO2, is especially concerning in parts of Siberia where melting permafrost is causing strange natural phenomena to literally bubble up from underground. In an interview with Alex Verbeek, Crowther said these effects could be worsened by carbon emissions from soil deposits.
To slow down or offset these processes, things like carbon sequestration and plant growth could help. But as the study notes, the net effect of such strategies require further investigation.
"Getting a handle on these kinds of feedbacks is essential if we're going to make meaningful projections about future climate conditions," Crowther added.
"Only then can we generate realistic greenhouse gas emission targets that are effective at limiting climate change."