Arctic Permafrost Melting 70 Years Sooner Than Expected

Arctic Permafrost Melting 70 Years Sooner Than Expected

SOURCE: Weather.com DATE: June 14, 2019 SNIP: Scientists studying climate change expected layers of permafrost in the Canadian Arctic to melt by the year 2090. Instead, it’s happening now. A new study published this week in the journal Geophysical Research Letters revealed that unusually warm summers in the Canadian High Arctic between 2003 and 2016 resulted in permafrost melt up to 240% higher than previous years. Louise Farquharson, a researcher at the Permafrost Laboratory at the University of Alaska Fairbanks and the study’s lead author, told weather.com the three areas of melting permafrost studied in remote northern Canada are believed to have been frozen for thousands of years. “This change is unprecedented on this kind of time scale,” Farquharson said. She noted that while scientists had predicted the permafrost wouldn’t melt for another 70 years, those forecasts didn’t take into account the unusually warm summers that have happened in recent years. While researchers believe all indicators point to warmer temperatures continuing, there’s no way to know for sure just how quickly the permafrost will continue to...
Climate crisis: Alaska is melting and it’s likely to accelerate global heating

Climate crisis: Alaska is melting and it’s likely to accelerate global heating

SOURCE: The Guardian DATE: June 14, 2019 SNIP: A city in western Alaska has lost a huge stretch of riverbank to erosion that may turn it into an island, amid renewed warnings from scientists over the havoc triggered by the accelerating melting of the state’s ice and permafrost. Residents of the small city of Akiak were alarmed to find the Kuskokwim River suddenly much closer to housing after about 75-100ft of riverbank disappeared over the course of just a few hours. The erosion, which occurred late last month, stripped away the riverbank for the entire length of Akiak, which has a population of around 340. “The changes are really accelerating in Alaska,” said Susan Natali, a scientist and Arctic expert at the Woods Hole Research Center in Massachusetts. “It’s pretty likely this riverbank in Akiak was lost because of thawing permafrost, given where it’s situated and the warm winter and spring they’ve had. It’s not a problem that’s going to go away.” Alaska has just experienced its warmest spring on record, breaking a record only set in 2016. Since the 1970s, springtime in the state has heated up by around 2.2C (4F), double the global temperature rise of the past century. Scientists recently found [thawing permafrost] could trigger a dangerous acceleration of global heating that would cause tens of trillions of dollars in climate-related damage. A separate study found that parts of the Canadian Arctic are experiencing a rate of permafrost thaw six times the long-term...
No laughing matter

No laughing matter

SOURCE: Harvard Gazette DATE: June 6, 2019 SNIP: About a quarter of the Northern Hemisphere is covered in permafrost. Now, it turns out these permanently frozen beds of soil, rock, and sediment are actually not so permanent: They’re thawing at an increasing rate. Human-induced climate change is warming these lands, melting the ice and loosening the soil, and that can cause severe damage. Forests are falling; roads are collapsing; and, in an ironic twist, the warmer soil is releasing even more greenhouse gases, which could further exacerbate the effects of climate change. Shortly after scientists first noticed signs of thaw in the early 1970s, they rushed to monitor emissions of the two most influential greenhouse gases — carbon dioxide and methane. But until recently, the threat of the third-most-prevalent gas, nitrous oxide (N2O) — known in dentistry as laughing gas — has largely been ignored. In a 2010 paper, the Environmental Protection Agency (EPA) rated permafrost nitrous oxide emissions as “negligible,” and few studies counter this claim. But a paper published this month in the journal Atmospheric Chemistry and Physics shows that nitrous oxide emissions from thawing Alaskan permafrost are about 12 times higher than previously assumed. Since N2O traps heat nearly 300 times more efficiently than carbon dioxide does, this revelation could mean that the Arctic — and the global climate — are in more danger than we thought. “Much smaller increases in nitrous oxide would entail the same kind of climate change that a large plume of CO2would cause,” said Wilkerson, the paper’s first author and a Ph.D. student at the Graduate School of Arts and Sciences...
Widespread permafrost degradation seen in high Arctic terrain

Widespread permafrost degradation seen in high Arctic terrain

SOURCE: Phys.org DATE: May 23, 2019 SNIP: A McGill-led study published recently in Environmental Research Letters presents close to 30 years of aerial surveys and extensive ground mapping of the Eureka Sound Lowlands area of Ellesmere and Axel Heiberg Islands located at approximately 80 °N. The research focuses on a particular landform (known as a retrogressive thaw slump) that develops as the ice within the permafrost melts and the land slips down in a horseshoe-shaped feature. The presence of these landforms is well documented in the low Arctic. But due to the extremely cold climate in high Arctic polar deserts (where average annual ground and air temperatures are -16.5 °C/2.3 °F, and -19.7 °C /-3.46 °F, respectively), and the fact that the permafrost is over 500 metres (or about 1/3 of a mile) thick, it had been assumed this landscape was stable. But the McGill-led research team found that this has not been the case. “Our study suggests that the warming climate in the high Arctic, and more specifically the increases in summer air temperatures that we have seen in recent years, are initiating widespread changes in the landscape,” says Melissa Ward Jones, the study’s lead author and a Ph.D. candidate in McGill’s Department of Geography. There has been a widespread development of retrogressive thaw slumps in high Arctic polar deserts over a short period, particularly during the unusually warm summers of 2011, 2012 and 2015. The absence of vegetation and layers of organic soil in these polar deserts make permafrost in the area particularly vulnerable to increases in summer air temperatures. Despite its relatively short duration, the thaw...
Rapid Permafrost Thaw Unrecognized Threat to Landscape, Global Warming Researcher Warns

Rapid Permafrost Thaw Unrecognized Threat to Landscape, Global Warming Researcher Warns

SOURCE: University of Guelph DATE: April 30, 2019 SNIP: A “sleeping giant” hidden in permafrost soils in Canada and other northern regions worldwide will have important consequences for global warming, says a new report led by University of Guelph scientist Merritt Turetsky. Scientists have long studied how gradual permafrost thaw occurring over decades in centimetres of surface soils will influence carbon release to the atmosphere. But Turetsky and an international team of researchers are looking at something very different: rapid collapse of permafrost that can transform the landscape in mere months through subsidence, flooding and landslides. “We are watching this sleeping giant wake up right in front of our eyes,” said Turetsky, who holds the Canada Research Chair in Integrative Ecology. Describing the formation of thaw lakes and landslides triggering mass movement of soil and sediment into rivers and streams, Turetsky adds: “It’s happening faster than anyone predicted. We show that abrupt permafrost thawing affects less than 20 per cent of the permafrost region, but carbon emissions from this relatively small region have the potential to double the climate feedback associated with permafrost...