OMEN
04-04-2008, 09:48 PM
Climate change and a warming Arctic Ocean are having a dramatic effect on the vast network of lakes in the Northwest Territories' Mackenzie Delta, according to a geographer who has discovered rising water levels over the last few decades.
Recent data shows water levels have risen in 60 per cent of the Delta's 45,000 freshwater lakes over the past 30 years, with some low-lying lakes going up by nearly 30 centimetres.
The results are about three times more severe than predicted, said Lance Lesack, a geography and biological sciences professor at Simon Fraser University in B.C.
"I was shocked, actually. I had no idea that the water level regime would actually change that much," Lesack told CBC News in an interview Thursday.
Receding sea ice on the Arctic Ocean means more ocean water is free to be pushed around by storm surges, which Lesack said may be driving water inland and filling up the Delta's lakes.
"Nobody, as far as I can tell, really seemed to have thought about this enhanced storm surge effect," he said.
"All around, the entire Arctic is going to be a very different place than it is right now."
People living in the coastal community of Tuktoyaktuk, N.W.T., have seen the effects of storm surges, which Mayor Mervin Gruben said were once dubbed "hundred-year storms."
"They're starting to be happening more often," Gruben said.
"In my lifetime, I've seen three of them, and I'm only 45 now. So with the west wind ... we get some pretty big waves and we have some major erosion in those storms."
Lesack said Delta residents may see the effects of rising lake levels when they are out on the land. "We think one of the effects is potentially loss of biodiversity from the system," he said.
"You might see that trapping and hunting will start to change in ways that you might not have thought of."
On the other hand, Lesack said the rising water levels could also increase fish habitats in the area. However, he added that the storm surges may introduce harmful saltwater into the Delta's freshwater lakes.
CBC
Recent data shows water levels have risen in 60 per cent of the Delta's 45,000 freshwater lakes over the past 30 years, with some low-lying lakes going up by nearly 30 centimetres.
The results are about three times more severe than predicted, said Lance Lesack, a geography and biological sciences professor at Simon Fraser University in B.C.
"I was shocked, actually. I had no idea that the water level regime would actually change that much," Lesack told CBC News in an interview Thursday.
Receding sea ice on the Arctic Ocean means more ocean water is free to be pushed around by storm surges, which Lesack said may be driving water inland and filling up the Delta's lakes.
"Nobody, as far as I can tell, really seemed to have thought about this enhanced storm surge effect," he said.
"All around, the entire Arctic is going to be a very different place than it is right now."
People living in the coastal community of Tuktoyaktuk, N.W.T., have seen the effects of storm surges, which Mayor Mervin Gruben said were once dubbed "hundred-year storms."
"They're starting to be happening more often," Gruben said.
"In my lifetime, I've seen three of them, and I'm only 45 now. So with the west wind ... we get some pretty big waves and we have some major erosion in those storms."
Lesack said Delta residents may see the effects of rising lake levels when they are out on the land. "We think one of the effects is potentially loss of biodiversity from the system," he said.
"You might see that trapping and hunting will start to change in ways that you might not have thought of."
On the other hand, Lesack said the rising water levels could also increase fish habitats in the area. However, he added that the storm surges may introduce harmful saltwater into the Delta's freshwater lakes.
CBC