What shallow lakes are telling us about the changing Arctic climate

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Scientists in Arctic Alaska are studying the permafrost changes under shallow Arctic lakes and what they found was surprising. (Courtesy Chris Arp)
Scientists in Arctic Alaska are studying the permafrost changes under shallow Arctic lakes and what they found was surprising. (Courtesy Chris Arp)
Permafrost changes are among the most alarming consequences of warming Arctic temperatures.

All across the Arctic, the shifts in how permafrost behaves is affecting everything from infrastructure to ground moisture.

But  research recently published in the journal Geophysical Research Letters  suggests there are also changes to the permafrost we can’t see, namely in shallow lakes that have been warming in places like Arctic Alaska over the last 30 years.

“The rates of warming were higher than we expected to see, and the depths where (this is) occurring are actually shallower than we expected to see,” said Chris Arp a research assistant professor at the University of Alaska Fairbanks and the study’s lead author.

Feature Interview

To find out more, Eye on the Arctic spoke with scientist Chris Arp about lakes, climate and some of researchers’ surprising findings:

Years of research

The research was done on the Arctic coastal plain in northern Alaska where approximately 20 to 30 per cent of the land is covered by lakes.

The group took measurements both in the winter and the summer using sensors to measure temperature both at the bottom and at the surface of the lakes, as well as ice thickness.

“There’s been a lot of monitoring of terrestrial permafrost, so even through it’s warming rapidly we don’t expect to see a thaw near the surface  of that permafrost for 50 to 100 years,” Arp said. “Whereas this permafrost below these shallow lakes is warming up and thawing right now.”

“With sea ice decline, we’re seeing more precipitation and if that comes as rain or snow that can have an impact on these (shallow) lakes,” says researcher Christoper Arp.
“With sea ice decline, we’re seeing more precipitation and if that comes as rain or snow that can have an impact on these (shallow) lakes,” says researcher Chris Arp. (Courtesy Chris Arp)
Role of sea ice

The network of lakes across northern Alaska play a key role in everything from habitat to how the landscape functions. That means warming temperatures will have a series of both positive and negative effects for the nature and people of the North, Arp said.

Warming lakes mean less ice so more habitat for overwintering fish, he says.  The increase in availability of liquid water could also make it easier to build ice roads, something the petroleum industry relies on in Arctic Alaska.

But the continued warming of the North will also mean the release of more greenhouse gases as the permafrost thaws along with the erosion of lakes.

Measurements were taken both at the top and bottom of shallow Arctic lakes, many measuring only around one metre deep. (Courtesy Chris Arp)
Measurements were taken both at the top and bottom of shallow Arctic lakes, many measuring only around one metre deep. (Courtesy Chris Arp)

Arp says the next steps will be to examine how sea ice is affecting permafrost and lakes in the Arctic.

“With sea ice decline, we’re seeing more precipitation and if that comes as rain or snow that can have an impact on these lakes,” Arp said. “If we get a lot more snowfall in the early part of the winter, that really insulates the ice and it grows a lot thinner.

“It’s hard to know exactly what’s going to happen with sea ice but everything points to really rapidly declining extents and a lot more open water in the fall and early winter so it’s going to be interesting to see how terrestrial ecosystems and lakes respond to that.”

Write to Eilís Quinn at eilis.quinn(at)cbc.ca

Related stories from around the North:

Canada: Canadian river carries carbon from thawing permafrost to sea, Alaska Dispatch News

Finland:  Climate change brings new insect arrivals to Finland, Yle News

Greenland: Can we still avert irreversible ice sheet melt?, Deutsche Welle’s Ice-Blog

Norway:  UN Secretary-General to visit Norwegian Arctic, Eye on the Arctic

Russia:  Ancient virus found in Arctic permafrost, Alaska Dispatch News

Sweden:  How will global warming affect the average Swede?, Radio Sweden

United States:  Arctic future – not so permafrost, Deutsche Welle’s Iceblogger

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Eilís Quinn, Eye on the Arctic

Eilís Quinn, Eye on the Arctic

Eilís Quinn is a journalist and manages Radio Canada International’s Eye on the Arctic circumpolar news project. At Eye on the Arctic, Eilís has produced documentary and multimedia series about the issues facing aboriginal peoples in the circumpolar world. Her documentary Bridging the Divide was a finalist at the 2012 Webby Awards. In her weekly column on RCInet.ca, she focuses on the people and issues making a difference in northern Canada. Eilís began reporting on the North in 2001. Her work as a reporter in Canada and the United States, and as TV host for the Discovery/BBC Worldwide series "Best in China" has taken her to some of the world’s coldest regions including the Tibetan mountains, Greenland, Arctic Russia, Yukon, Nunavut and Nunavik. Read Eilís Quinn's articles

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