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Wednesday, February 10, 2010
Lake Erie could freeze over entirely for first time in years
Frozen water tames lake effect, shipping
The power is running out on the Lake Erie snow machine.
And more cold weather could just about pull the plug on it.
The lake is about 90 to 95 percent ice-covered, and more cold temperatures forecast for the next week or so could freeze the entire lake, National Weather Service meteorologists in Cleveland said.
"We're thinking it probably will ice over the rest of the way,'' said weather service meteorologist Karen Oudeman.
Weather service meteorologist Robert LaPlante said Tuesday that the remaining open area extends from Long Point, Ontario, southeast to the New York state shoreline. Satellite images also indicate some waters just north and east of Erie, off Pennsylvania, are also ice-free.
An ice-covered lake could mean good news for winter-weary residents, or not-so-good news for people who can't get enough of the snow.
The ice-over also could mean a later start to the Lake Erie shipping season.
Complete or nearly complete ice cover lessens the chance of lake-effect snowstorms, which occur when cold air passes over warmer bodies of water, building up clouds and dumping snow downwind. Inland snowbelt areas are typically hit the hardest.
"The moisture source really isn't there when it's frozen. There's less moisture to work with,'' Oudeman said.
But here's three reasons why you shouldn't put away your snow shovels and snowblowers just yet:
- The Lake Erie snow machine can be turned on again by small, open areas of water, or high winds that break up the ice. "It's kind of a fragile ice setting out there,'' LaPlante said. "A county or two-sized area opens up and all of a sudden you have (the potential for) a snowstorm.''
Oudeman said even a completely iced-over lake typically has some open pockets of water. "It doesn't usually look like a perfect ice rink, because the wind is pushing ice and water in different directions. It's very dynamic,'' she said.
Even so, small, open areas of water would produce less lake-effect snow, she said.
- While most of our lake-effect snow comes from westerly winds over Lake Erie, some of it comes from Lake Huron, which is mostly still open, LaPlante said.
"If we get a northwest flow of cold, arctic air, it can flow off Lake Huron and affect northwest Pennsylvania,'' he said.
- And synoptic weather systems -- large-scale patterns that affect a larger part of the nation -- could bring snow to northwestern Pennsylvania, too, the meteorologists said. A storm system that started Tuesday, expected to move from Iowa to the East Coast, was such a system, LaPlante said.
The lake hasn't completely frozen over since the winter of 1995-96, though it virtually froze over a year later, at 99.6 percent, on Jan. 28, 1997, said George Leshkevich, a scientist with the National Oceanic and Atmospheric Administration's Great Lakes Environmental Research Laboratory in Ann Arbor, Mich.
But the ice cover reached 90.2 percent or higher five times from 2000-01 through 2008-09, he said. Leshkevich's data comes from the National Ice Center, an agency that comes under the umbrella of NOAA, the U.S. Navy and the U.S. Coast Guard.
But even at 90 percent, Leshkevich said much of the lake-effect snow potential is diminished.
This season, as of 5 p.m. Tuesday, Erie recorded 62.1 inches of snowfall at Erie International Airport, far below the pace of the seasonal total of 145.8 inches for 2008-09.
But recent ice cover is only one possible reason for the lower amount.
"There is a lot of variability from year to year,'' LaPlante said.
This season, November was mild, cold temperatures in early January gave way to moderate temperatures later in the month, and the region experienced few periods with below-normal temperatures that contribute to lake-effect storms, LaPlante said. Also, he said, the region has been spared large synoptic storms like the one that buried Pittsburgh and much of the East Coast over the weekend.
A complete ice cover of Lake Erie also could affect the multi-billion-dollar Great Lakes shipping trade, said Glen Nekvasil, spokesman for the Lake Carriers' Association, a Cleveland-based trade group representing U.S.-flagged vessels on the Great Lakes.
A later start to the shipping season is possible if "formidable'' ice forms on the lake, though U.S. Coast Guard ice breakers are available, he said. The ice thickness varies throughout the lake, the weather service's Oudeman said.
The U.S. Coast Guard has eight ice breakers stationed in the Great Lakes, and brought a ninth one from the East Coast for this winter, Nekvasil said.
But Nekvasil said only one is modern and capable of operating in all conditions, and he said Canada has scaled back its number of Great Lakes ice breakers.
The shipping season on Lake Erie typically starts about March 15, with coal shipments from Ohio ports to Canada and the United States, Nekvasil said.
The "starting gun'' for the rest of the Great Lakes is typically March 25, with the opening of the Soo Locks at Sault Ste. Marie, Mich., he said.
Winter-weary residents have their eyes on a different season, the start of spring on March 20.
But with a lake that could freeze over entirely for the first time in 14 years, that seems like a long way off.
The lake is about 90 to 95 percent ice-covered, and more cold temperatures forecast for the next week or so could freeze the entire lake, National Weather Service meteorologists in Cleveland said.
"We're thinking it probably will ice over the rest of the way,'' said weather service meteorologist Karen Oudeman.
Weather service meteorologist Robert LaPlante said Tuesday that the remaining open area extends from Long Point, Ontario, southeast to the New York state shoreline. Satellite images also indicate some waters just north and east of Erie, off Pennsylvania, are also ice-free.
An ice-covered lake could mean good news for winter-weary residents, or not-so-good news for people who can't get enough of the snow.
The ice-over also could mean a later start to the Lake Erie shipping season.
Complete or nearly complete ice cover lessens the chance of lake-effect snowstorms, which occur when cold air passes over warmer bodies of water, building up clouds and dumping snow downwind. Inland snowbelt areas are typically hit the hardest.
"The moisture source really isn't there when it's frozen. There's less moisture to work with,'' Oudeman said.
But here's three reasons why you shouldn't put away your snow shovels and snowblowers just yet:
- The Lake Erie snow machine can be turned on again by small, open areas of water, or high winds that break up the ice. "It's kind of a fragile ice setting out there,'' LaPlante said. "A county or two-sized area opens up and all of a sudden you have (the potential for) a snowstorm.''
Oudeman said even a completely iced-over lake typically has some open pockets of water. "It doesn't usually look like a perfect ice rink, because the wind is pushing ice and water in different directions. It's very dynamic,'' she said.
Even so, small, open areas of water would produce less lake-effect snow, she said.
- While most of our lake-effect snow comes from westerly winds over Lake Erie, some of it comes from Lake Huron, which is mostly still open, LaPlante said.
"If we get a northwest flow of cold, arctic air, it can flow off Lake Huron and affect northwest Pennsylvania,'' he said.
- And synoptic weather systems -- large-scale patterns that affect a larger part of the nation -- could bring snow to northwestern Pennsylvania, too, the meteorologists said. A storm system that started Tuesday, expected to move from Iowa to the East Coast, was such a system, LaPlante said.
The lake hasn't completely frozen over since the winter of 1995-96, though it virtually froze over a year later, at 99.6 percent, on Jan. 28, 1997, said George Leshkevich, a scientist with the National Oceanic and Atmospheric Administration's Great Lakes Environmental Research Laboratory in Ann Arbor, Mich.
But the ice cover reached 90.2 percent or higher five times from 2000-01 through 2008-09, he said. Leshkevich's data comes from the National Ice Center, an agency that comes under the umbrella of NOAA, the U.S. Navy and the U.S. Coast Guard.
But even at 90 percent, Leshkevich said much of the lake-effect snow potential is diminished.
This season, as of 5 p.m. Tuesday, Erie recorded 62.1 inches of snowfall at Erie International Airport, far below the pace of the seasonal total of 145.8 inches for 2008-09.
But recent ice cover is only one possible reason for the lower amount.
"There is a lot of variability from year to year,'' LaPlante said.
This season, November was mild, cold temperatures in early January gave way to moderate temperatures later in the month, and the region experienced few periods with below-normal temperatures that contribute to lake-effect storms, LaPlante said. Also, he said, the region has been spared large synoptic storms like the one that buried Pittsburgh and much of the East Coast over the weekend.
A complete ice cover of Lake Erie also could affect the multi-billion-dollar Great Lakes shipping trade, said Glen Nekvasil, spokesman for the Lake Carriers' Association, a Cleveland-based trade group representing U.S.-flagged vessels on the Great Lakes.
A later start to the shipping season is possible if "formidable'' ice forms on the lake, though U.S. Coast Guard ice breakers are available, he said. The ice thickness varies throughout the lake, the weather service's Oudeman said.
The U.S. Coast Guard has eight ice breakers stationed in the Great Lakes, and brought a ninth one from the East Coast for this winter, Nekvasil said.
But Nekvasil said only one is modern and capable of operating in all conditions, and he said Canada has scaled back its number of Great Lakes ice breakers.
The shipping season on Lake Erie typically starts about March 15, with coal shipments from Ohio ports to Canada and the United States, Nekvasil said.
The "starting gun'' for the rest of the Great Lakes is typically March 25, with the opening of the Soo Locks at Sault Ste. Marie, Mich., he said.
Winter-weary residents have their eyes on a different season, the start of spring on March 20.
But with a lake that could freeze over entirely for the first time in 14 years, that seems like a long way off.
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