Ice coverage on the Great Lakes hit record lows in January and is well below the seasonal average, prompting concerns from experts about the environmental impact caused by a lack of ice.
As of Jan. 25, 7.7 per cent of the Great Lakes have frozen over, based on data from the National Oceanic and Atmospheric Administration, a U.S. science agency.
Ice levels were as low as 1.8 per cent on Jan. 15, a record-low for the mid-January period.
The abnormally low levels in 2021 reflect a longstanding trend of Great Lakes ice coverage declining by about 5 per cent per decade since the 1970s.
“The downward trend is a trend by global warming,” said Jia Wang, an ice climatologist with U.S. National Oceanic and Atmospheric Administration.
But this year’s significant low is the result of local weather patterns, which have the biggest impact on ice formation on the lakes.
“On the Great Lakes, our local climate, like surface air temperature, is the main determinant of if the ice is severe or mild,” Wang said.
He projects the maximum ice coverage this year will be 30 per cent, sometime in February or early March. The long-term average is 53 per cent.
Lake Huron is hovering around 15 per cent ice coverage. The late-January long-term average is about 35 per cent.
Erie, one of the shallowest lakes, is sitting at 8.8 per cent ice coverage as of Jan. 25, and that figure had been less than 1 per cent as early as last week, a far cry from the almost 50 per cent average.
Wang said low ice levels bring a “negative impact more than a positive impact.”
Save for a potential boon for lake freight shipping, which would be less reliant on ice breakers, lack of ice can devastate the Great Lakes environment.
“What’s worrisome is this higher frequency of lower ice,” said Michael McKay, executive director of the Great Lakes Institute for Environmental Research at the University of Windsor, adding years with abnormally low ice are becoming more common.
Since 2000, 14 of the last 21 years have had ice coverage levels below the 53 per cent average.
McKay said ice cover on the Great Lakes has dropped 70 to 75 per cent in the past 40 to 50 years. “It has really run parallel to what we’re seeing the arctic and Antarctic,” he said.
The effects of low ice on the Great Lakes can be felt throughout Southwestern Ontario.
“This is going to exacerbate other problems we find in the lakes,” McKay said.
One major challenge is the increased risk of shoreline erosion without the protection of ice coverage.
“Ice cover in the winter can help protect coastal communities from erosion,” McKay said. “In Southwestern Ontario, we’ve seen regions on the Lake Erie coast that have caved in … in part because it no longer has had that protection because of ice cover and waves just keep slamming.”
The runoff effects extend to inland communities too, like London and Huron and Perth Counties, which often are hit by lake effect snowstorms.
Without ice on the lakes, prevailing winds pick up more precipitation and dump it in communities downwind.
“We’ll continue to get hit by large snowfall when lakes remain ice-free,” McKay said.
Blooms of cyanobacteria which have plagued the Great Lakes in recent years, also can be made worse by a lack of ice.
Ice cover calms lake water in the winter and allows some runoff nutrients and contaminants to settle in the sediment.
Without ice cover, more resuspension events occur, reintroducing the contaminates into the water, which contributes to cyanobacteria blooms.
Fish too are impacted, with some species, like white fish, spawning in winter months and needing still waters so their eggs are not disturbed.
And beyond the environmental impacts, McKay said less ice on the Great Lakes means losing a “cultural identified” for Canadians.
“It's part of our identity, certainly in Canada, to have outdoor skating and ice fishing,” he said.
While McKay said it may be past the point where actions to slow climate change could yield visible results within our lifetime, he said attention should still be paid to mitigating the effects that are indirectly related to the declines in Great Lakes ice cover.
The good news, he said, is the waters are resilient.
“Time and again, we’ve seen the lakes assaulted by various pressures, usually human-induced, things ranging from containments to invasive species, the (cyanobacteria) blooms,” McKay said. “It may not be exactly the same as it was before, but there’s a lot of resiliency in the lakes and they seem to bounce back and still be intact and important ecosystems.”
(AS OF JAN. 25, 2021)
Superior: 4 per cent
Michigan: 6.7 per cent
Huron: 15.3 per cent
Erie: 8.8 per cent
Ontario: 1.1 per cent
St. Clair*: 33.8 per cent
Great Lakes average: 7.7 per cent
*Lake St. Clair is not technically a Great Lake
maxmartin@postmedia.com
Twitter.com/MaxatLFPress
Max Martin, Local Journalism Initiative Reporter, London Free Press
As of Jan. 25, 7.7 per cent of the Great Lakes have frozen over, based on data from the National Oceanic and Atmospheric Administration, a U.S. science agency.
Ice levels were as low as 1.8 per cent on Jan. 15, a record-low for the mid-January period.
The abnormally low levels in 2021 reflect a longstanding trend of Great Lakes ice coverage declining by about 5 per cent per decade since the 1970s.
“The downward trend is a trend by global warming,” said Jia Wang, an ice climatologist with U.S. National Oceanic and Atmospheric Administration.
But this year’s significant low is the result of local weather patterns, which have the biggest impact on ice formation on the lakes.
“On the Great Lakes, our local climate, like surface air temperature, is the main determinant of if the ice is severe or mild,” Wang said.
He projects the maximum ice coverage this year will be 30 per cent, sometime in February or early March. The long-term average is 53 per cent.
Lake Huron is hovering around 15 per cent ice coverage. The late-January long-term average is about 35 per cent.
Erie, one of the shallowest lakes, is sitting at 8.8 per cent ice coverage as of Jan. 25, and that figure had been less than 1 per cent as early as last week, a far cry from the almost 50 per cent average.
Wang said low ice levels bring a “negative impact more than a positive impact.”
Save for a potential boon for lake freight shipping, which would be less reliant on ice breakers, lack of ice can devastate the Great Lakes environment.
“What’s worrisome is this higher frequency of lower ice,” said Michael McKay, executive director of the Great Lakes Institute for Environmental Research at the University of Windsor, adding years with abnormally low ice are becoming more common.
Since 2000, 14 of the last 21 years have had ice coverage levels below the 53 per cent average.
McKay said ice cover on the Great Lakes has dropped 70 to 75 per cent in the past 40 to 50 years. “It has really run parallel to what we’re seeing the arctic and Antarctic,” he said.
The effects of low ice on the Great Lakes can be felt throughout Southwestern Ontario.
“This is going to exacerbate other problems we find in the lakes,” McKay said.
One major challenge is the increased risk of shoreline erosion without the protection of ice coverage.
“Ice cover in the winter can help protect coastal communities from erosion,” McKay said. “In Southwestern Ontario, we’ve seen regions on the Lake Erie coast that have caved in … in part because it no longer has had that protection because of ice cover and waves just keep slamming.”
The runoff effects extend to inland communities too, like London and Huron and Perth Counties, which often are hit by lake effect snowstorms.
Without ice on the lakes, prevailing winds pick up more precipitation and dump it in communities downwind.
“We’ll continue to get hit by large snowfall when lakes remain ice-free,” McKay said.
Blooms of cyanobacteria which have plagued the Great Lakes in recent years, also can be made worse by a lack of ice.
Ice cover calms lake water in the winter and allows some runoff nutrients and contaminants to settle in the sediment.
Without ice cover, more resuspension events occur, reintroducing the contaminates into the water, which contributes to cyanobacteria blooms.
Fish too are impacted, with some species, like white fish, spawning in winter months and needing still waters so their eggs are not disturbed.
And beyond the environmental impacts, McKay said less ice on the Great Lakes means losing a “cultural identified” for Canadians.
“It's part of our identity, certainly in Canada, to have outdoor skating and ice fishing,” he said.
While McKay said it may be past the point where actions to slow climate change could yield visible results within our lifetime, he said attention should still be paid to mitigating the effects that are indirectly related to the declines in Great Lakes ice cover.
The good news, he said, is the waters are resilient.
“Time and again, we’ve seen the lakes assaulted by various pressures, usually human-induced, things ranging from containments to invasive species, the (cyanobacteria) blooms,” McKay said. “It may not be exactly the same as it was before, but there’s a lot of resiliency in the lakes and they seem to bounce back and still be intact and important ecosystems.”
(AS OF JAN. 25, 2021)
Superior: 4 per cent
Michigan: 6.7 per cent
Huron: 15.3 per cent
Erie: 8.8 per cent
Ontario: 1.1 per cent
St. Clair*: 33.8 per cent
Great Lakes average: 7.7 per cent
*Lake St. Clair is not technically a Great Lake
maxmartin@postmedia.com
Twitter.com/MaxatLFPress
Max Martin, Local Journalism Initiative Reporter, London Free Press
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