Bubbles of methane rising through Smith Lake in Fairbanks, Alaska, highlight an accelerating climate shift as frozen permafrost thaws. Researchers warn that decaying organic matter trapped for millennia is now releasing greenhouse gases faster than the Arctic can absorb them, adding significant new warming to the global atmosphere.
As Ted Schuur walked along the edge of Smith Lake in Fairbanks, Alaska, bubbles of methane broke through the muck underfoot (Source 1). These releases come from decomposing plants and animals that remained locked in the frozen ground for thousands of years until rising temperatures set off widespread thawing.
Permafrost is ground that stays below 32 degrees Fahrenheit, or zero degrees Celsius, for a minimum of two years and frequently for centuries or millennia (Source 2). It exists across Alaska, Canada, Siberia, Antarctica, and high mountain elevations (Source 3). For generations, this frozen layer performed two vital functions: it anchored northern communities and industrial infrastructure while locking away decaying organic matter so it could not transform into greenhouse gases (Source 1).
Why the Arctic Carbon Balance Shifted
That stabilizing function has broken down because the Arctic is warming four times faster than the rest of the planet (Source 1). For millennia, the northern region acted as a net carbon sink (Source 1). Cold-region plants pulled carbon dioxide out of the air, and freezing conditions buried that material securely in the ground (Source 1). A few years ago, rising temperatures caused that system to tip, turning the tundra into a net source of emissions (Source 1).
“Once you start leaking this carbon out, there’s so much in the ground that it’s not going to shut off.”
Ted Schuur, ecologist at Northern Arizona University
Schuur described the development as one of climate change’s scary tipping points, noting that essentially every year is setting a permafrost record
(Source 1). Stockholm University permafrost expert Gustaf Hugelius characterized the entire dynamic by stating that the permafrost system is really like a sleeping giant
(Source 1). Columbia University ecologist Duncan Menge emphasized that the Arctic now adds to global carbon burdens rather than reducing them (Source 1).
Projections and Omissions in Global Climate Models
Scientists estimate that permafrost holds three times as much carbon as is currently present in the Earth’s atmosphere (Source 1). Two separate studies project that by the end of the century, these escaping gases will add nearly half a degree of warming—about a quarter of a degree Celsius—beyond what fossil fuel emissions produce (Source 1). Researchers point out that this additional heat equals the contribution of a major industrialized nation like the United States or the entirety of Europe over the same timeframe (Source 1).
A study co-authored by Sue Natali of the Woodwell Climate Research Center reported that permafrost thaw, combined with other warming-induced emissions
from wildfires, wetlands, and lakes, will likely boost overall warming by 20% by the end of the century (Source 1). University of Victoria climate scientist Andrew Weaver, who first calculated the half-degree permafrost warming figure in a 2012 study, noted that while the impact does not warrant disaster scenarios, it represents an extra burden that we’re going to have to deal with
(Source 1).
A primary concern for researchers is that political and scientific projections rarely account for these permafrost emissions (Source 1). The United Nations projects that without policy changes, global temperatures will rise by 2.6 degrees Celsius, or 4.7 degrees Fahrenheit, above pre-industrial levels by the end of the century, an estimate that omits several tenths of a degree stemming directly from thawing permafrost (Source 1).
Land Collapse and Infrastructure Risks in Northern Regions
Beyond its effect on the global carbon budget, thawing permafrost actively destabilizes the land surface (Source 2). While solidly frozen ground provides a stable foundation for mountains and skyscrapers, thawed ground loses its structural strength (Source 2).
Loss of firmness in northern terrain has direct physical consequences. Berkeley Earth climate scientist Robert Rohde noted that record-setting regional heat waves this summer contributed to a glacier collapse in Nepal that triggered flooding and killed more than 1,000 people (Source 2). Dmitry Streletskiy, a permafrost scientist at George Washington University and lead author of an August study documenting widespread permafrost thaw across most of the Northern Hemisphere, stated that degraded frozen ground was likely one of several contributing factors in the Nepal disaster (Source 3).
