Great Lakes remarkably ice-free compared to past two winters
Meteorologist/Science Writer
Wednesday, January 13, 2016, 1:44 PM - It's been very cold and snowy in the Great Lakes area as of late, but despite that, the lakes themselves remain remarkably ice-free for this time of year.
One indication of how cold any winter has been so far in Canada is to take a look at exactly how much of the Great Lakes have frozen over.
Look back just a year or two, and the Lakes were already well on their way to being in the top five years on record for annual ice coverage.
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| Ice coverage on the Great Lakes, showing 38.3% on Jan 11, 2014 (left) and 22.5% on Jan 11, 2015 (right). Areas shaded light grey through black indicate ice concentrations, while blue through green indicate water temperatures above freezing. Credit: NOAA Great Lakes Environmental Research Laboratory (GLERL) | |
Lake Erie, the shallowest of the lakes and thus the easiest one to completely freeze over, is a particularly good indicator of just how cold it gets in the region, as shown in the satellite images below. Although there was ice on the shores of the other lakes as well, much of their surfaces were obscured by cloud over the open water, thus spoiling the view from space.
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| Satellite imagery of Lake Erie, the shallowest of the Great Lakes, on Jan 12, 2014 (left) and Jan 10, 2015 (right). Credit: NASA Aqua MODIS/NASA Worldview | |
Since detailed record keeping began in 1973, Winter 1979 still maintains its record high ice coverage on the Great Lakes, at 94.7 per cent. Winter 2014 finished in 2nd place at 92.5 per cent, while 2015 came in as the 5th highest, after 1994 (3rd) and 1977 (4th).
Graph of annual maximum lake ice coverage, 1973-2015. Credit: NOAA Great Lakes Environmental Research Laboratory (GLERL)
In contrast, as of this week, on January 11, 2015, there is hardly any ice to be found on the lakes.
Ice extent on the Great Lakes, Jan 11, 2016. Credit: NOAA Great Lakes Environmental Research Laboratory (GLERL)
Only 3.8 per cent of the water is frozen over, compared to 22.5 per cent in 2015 and 38.3 per cent in 2014.
Satellite imagery, on Jan 4, 2016. Credit: NASA Aqua MODIS/NASA Worldview
Above is the clearest recent view of the Great Lakes from space, taken by the MODIS instrument on board NASA's Aqua Earth-observing satellite on January 4. Below is a more recent view, posted to social media by Weather Network meteorologist Dayna Vettese. The vast majority of the white in these two images is simply cloud.
A wintry look at the Great Lakes today from space pic.twitter.com/RWO4YeQ4Yq
— Dayna Vettese (@daynavettese) January 13, 2016
As many residents of southern Ontario have found out, all of this open, relatively warm lake water has been feeding lake effect snow streamers, as the winds blow across the lake and tap into that abundant supply of moisture.
With ice coverage so low on the Great Lakes so far this winter, it is only slightly behind 2012, when a mild winter meant that ice coverage had only reached around 3.7 per cent by January 15, and maxed out 12.9 per cent for the year.
Will this year's ice coverage get down that low again? Will we see the biggest 2-year dip in ice coverage since the 1996-1998 period (when the last "super" El Niño occurred)?
Or will chilly weather bring about ice growth like was seen in 2013, which was in the 3-4 per cent range in January and then climbed to over 38 per cent by mid-February, before gradually melting away?
Stay tuned for more updates on the state of Great Lakes ice coverage in the weeks to come.
Sources: NOAA GLERL | NASA Worldview
Watch Now: Weather Network meteorologist Jaclyn Whittal explains the science behind lake effect snow squalls.
