The feedbacks from climate change are on full display for all to see. These northern heatwaves have exceeded the worst-case climate scenario. Be kind to each other.
The heatwave in the Pacific Northwest that has caused hundreds of deaths and igniting wildfires has entered the southern extremities of the Yukon and the Northwest territories. This heat has rapidly melted any snow remaining on the ground and has caused the thawing of the top layer of the permanently frozen soil. The water from the thaw is unable to percolate down through the frozen layers below. That causes even more thawing. The fear is that the thawed soil will detach from the frozen layer and slump into nearby rivers. This process is known as solifluction.
Anna Desmarais writes in the CBC.
The N.W.T.'s season started very wet, with really fast snowmelt, Quinton said, with most of the water ending up in the landscape.
When that happens, there is more ground thaw — and even more permafrost thaw.
Fabrice Calmels, research chair of permafrost and geoscience at Yukon University, said these temperatures could speed up the thaw of the first active layer of soil.
That layer could then detach itself from a thicker, permanent layer underneath and slide into nearby rivers.
"You may have some small landslides on slopes," he said. "When permafrost melts, it changes hydrology, it changes vegetation. It's a very complicated process."
With these kinds of temperatures comes an elevated risk of wildfires, Calmels continued.
If that happens, it will burn away some of the vegetation that anchors the ground for permafrost, causing even more thaw.
There are 13 active forest fires in Yukon and nine in the N.W.T. as of Wednesday morning.
Mike Francie, a spokesperson for Yukon Wildland Fire Management, said there's an "increased risk of ignition" throughout central Yukon as thundershowers are expected in the forecast.
There has been increased flooding in the region due to the snowmelt and rivers are running higher than usual. Not only can permafrost thaw change landscapes, but it can release more molecules of methane and CO2 into the atmosphere warming the earth even faster, yet another vicious climate feedback. This area of Canada is warming 2.3 times the rest of the planet.
Military put on standby to evacuate fire-threatened towns in western Canada
Ottawa prepared Friday to send military aircraft and other help to evacuate towns and fight more than 100 wildfires in western Canada fueled by a record-smashing heat wave.
According to wildfire officials, at least 143 fires were active in British Columbia, 77 of them sparked in the last two days. Most were caused by lightning strikes.
Prime Minister Justin Trudeau said he would convene an incident response group later in the day to address the emergency needs of the province, adding that he already spoke with British Columbia’s premier, as well as local mayors and indigenous chiefs in communities under threat.
“We will be there to help,” he told a news conference.
That will include military helicopters and possibly Hercules turboprop transport planes, Defense Minister Harjit Sajjan earlier told public broadcaster CBC.
Read more: https://www.digitaljournal.com/world/military-put-on-standby-to-evacuate-fire-threatened-towns-in-western-canada/article#ixzz6zW9bGCf6