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Sunday, February 22, 2015

The Great Lakes' freeze-up is in full swing. Here's what it looks like


Can you tell it's cold here?
Currently experiencing a cold snap that will see temperatures drop to an anticipated low of -42 C by tomorrow morning.

The prolonged cold temperatures can be seen by the ice cover on the Great Lakes.

See the piece below from the Weather Network
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Daniel Martins 
Digital Reporter

The Weather Network


Sunday, February 22, 2015, 6:19 AM

Will ice levels on the Great Lakes reach record levels this winter? It's looking like we may have a shot. Lake-dwellers have noticed the massive waterways are well into their annual ice up, more than 80 per cent frozen over on Saturday.

And that's actually around 10 points more ice coverage than the same day last year, when the maximum reached 92.5 per cent - just a stone's throw away from the all-time record of 94.7 per cent, from way back in 1979.

Time will tell if 2015 is the year that record is toppled. For now, here's what our lakes are looking like.



Lake Superior



Ice coverage on February 21: 91.4 per cent
2014 maximum: 95.7 per cent

Lake Superior is famously the coldest and largest of the Great Lakes, with ice lingering into June in some years.

But despite its northern location and cold air temperatures surrounding it, it has completely frozen over only once since record-keeping began in 1973. That was in the winter of 1978-1979, the same period where many of the other lakes set ice coverage records.

A big reason: Its large surface area means stronger winds, making for rough waters that can break up new ice, even though the lake is typically colder than the others.

As for when the ice exits, the water takes a long time to warm up, so May 24 lakeside revellers are usually out of luck. Last year, the lake was declared ice free as late as June 7, but with some small icebergs still spotted here and there.



Lake Michigan


coverage on February 21: 52.4 per cent
2014 maximum: 93.3 per cent

Lake Michigan is one of the lakes that hasn't frozen over since records began in 1973, but you won't have to look too hard to find its record coverage. It was last year.

The lake reached a 93.3 per cent coverage level, and with no sign of any warmth, NOAA officials were talking about the possibility of a new record in 2015.

It's hard to achieve a full ice up, because unlike its neighbours, Michigan sprawls across several latitudes north and south, making uniform ice coverage unlikely.

But it's well on its way, at a respectable 52.4 per cent on February 21, well above the 39 per cent it was on the same day last year.

One benefit: Increased ice coverage means less evaporation, such that the U.S. Army Corps of Engineers expects water levels to be higher in the spring.



Lake Huron



Ice cover on February 21: 93.1 per cent
2014 Maximum: 97.86 per cent

The difference between Lake Huron's maximum ice coverage last year and the all-time record is literally 0.02 per cent, according to Environment Canada.

The agency says the lake hit 97.86 per cent last year, a statistically insignificant whisker below its 1994 level, when it reached 97.88 per cent.

Lake Huron is a key thoroughfare for lake-going ship traffic heading to metropolises on lakes Erie and Ontario, so when the ice gets too thick, ship traffic grinds to a halt. CTV London quotes one source as saying the annual port shutdowns on the Lake Huron shores seemed to happen more suddenly this year.

For ships whose final destination is Lake Erie and beyond, they'll have to navigate from Sarnia and Windsor, a difficult trip that just last week took around four times longer than usual, with ice breaker assistance, according to The Observer.

We're sure companies factor the annual ice-up into their calculations, but a faster than can definitely have an impact on the bottom line.



Lake Erie


Cover on February 21: 96 per cent
2014 maximum: 96.4 per cent

At 96 per cent, Lake Erie was the most frozen over of the Great Lakes, just a smidgen below its 2014 maximum of 96.4. And if it ices over completely (which looks pretty likely), it will be the fourth time it has done so since records began in 1973, with the last full ice-up coming in 1996.

Unlike similar-sized Lake Ontario - which has never completely iced over since record keeping began - Lake Erie tends to be icier because it is shallower than its neighbour. It warms faster than its fellows, but also loses heat faster.

Current ice levels have caused their own headaches. The freighter Arthur M. Anderson is currently stuck in the ice near the Ohio coastline, and the U.S. Coast Guard has been battling to reach it for days.

They've been at it for so long the coast guard crew ran out of food, necessitating an air drop of more supplies. The Canadian Coast Guard was called in to help on Friday, and the two ships will join forces to free the Arthur M. Anderson.

Incidentally, Canadiana enthusiasts may recognize the trapped ship's name. The same vessel was the last to have made contact with the Edmund Fitzgerald before it went down on Lake Superior 40 years prior.



Lake Ontario


Cover on February 21: 52.7 per cent
2014 maximum: 61.5 per cent

Lake Ontario, as we said, is deeper than its neighbour. It loses heat slower, and boasts stronger underwater currents, and as such takes longer to ice up, and typically maxes out at a lower level.
On February 21, the lake was at 52.7 per cent ice coverage, slightly ahead of Lake Michigan but way more than the 13 per cent of this time last year.

But it was way higher last week, above 80 per cent on Wednesday, according to NOAA. In fact, observers say the lake's ice levels fluctuate more than other lakes.

That's because new ice can form quickly, and can be broken up just as rapidly by winds whipping up the lake waters into rough waves. All of the lakes are susceptible to this, but Lake Ontario's slow rate of heat loss makes the process more effective.

Anecdotal evidence suggests the lake has, in fact, totally frozen over in the past, but the official rankings say 85 per cent is the most it's ever reached since records began in 1973, the lowest maximum of all the lakes.



SOURCES: GLERLCoast WatchUMKC | Daily Mail | Holland Sentinel | CTV London | The Observer | Environment Canada | Windsor StarSyracuse.com

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