Canadian Permafrost Is Thawing 70 Years Earlier Than Scientists Expected
“Climate is now warmer than at any time in the last 5,000 or more years.”
The permafrost in Canada’s Arctic region is thawing 70 years earlier than scientists had initially predicted, Reuters reported. The discovery was made during an expedition led by a team from the University of Alaska Fairbanks, who said they were surprised by how quickly the unusually hot summers that have occurred in recent years have affected giant subterranean ice blocks that had remained frozen solid for several millennia.
“What we saw was amazing,” Vladimir Romanovsky, a professor of geophysics at the university, told Reuters. “It’s an indication that the climate is now warmer than at any time in the last 5,000 or more years.”
The team’s findings were published in the Geophysical Research Letters ahead of the United Nations climate negotiation meet in Bonn, Germany, this week. The research is based on data collected from exceptionally remote areas accessed by Romanovsky and his team with the help of a modified propeller plane.
"It's very likely that this phenomenon is affecting a much more extensive region and that's what we're going to look at next," Louise Farquharson, a post-doctoral researcher and co-author of the study, told Reuters.
Permafrost is a combination of soil, rock, and sand held together by ice that has been completely frozen for a minimum of two consecutive years. This permanently frozen ground comprises 24% of land in the Northern Hemisphere and is also found in the Southern Hemisphere.
Although the uppermost layer of the ground thaws in the summer sometimes, the lower layers remain frozen. Experts now believe that climate change could significantly accelerate melting throughout permafrost sheets. Additionally, the United Nations reported that the Arctic permafrost is expected to further shrink by 45% because of rapidly rising temperatures in the region.
Melting permafrost will affect the planet in a few ways. Most immediately, it will lead to higher sea levels around the world, as the ice that had previously been on land moves as water to the oceans.
It could also lead to a surge in greenhouse gas emissions.
When soil is frozen, plant material can’t decompose, which keeps carbon locked inside of it.Globally, these frozen soils hold an estimated 1,672 billion metric tonnes of carbon. When the permafrost melts, microbes begin decomposing the material, releasing greenhouse gases like carbon dioxide and methane into the atmosphere. These emissions then further contribute to global warming, which in turn leads to more thawing, creating a dangerous feedback loop.
Even if countries across the globe are able to keep global temperatures from rising more than 2 degrees Celsius above pre-industrial levels, the goal of the 2015 Paris climate agreement, such feedback loops can lead to risks that cannot be averted.
“We are seeing a big increase in the thaw of permafrost,'' Emily Osborne, program manager for the Arctic Research Program, NOAA, and editor of the Arctic Report Card, said. “The landscape is physically crumbling as a result… things are changing so fast, and in ways that researchers hadn’t even anticipated.”
"Thawing permafrost is one of the tipping points for climate breakdown and it's happening before our very eyes," said Jennifer Morgan, Executive Director of Greenpeace International.
"This premature thawing is another clear signal that we must decarbonise our economies, and immediately."