Lake Manitoba shows off rare ice formations
'It seemed to just spread out over the lake as far as I
could see,' says Steep Rock Kayak and Canoe owner
Mother Nature has turned Lake Manitoba into a visual art
project that has an ice expert in awe.
What would typically be a flat, frozen surface has been
turned into something more resembling pebbles and stones, as far as the eye can
see.
In another area, the water has crystallized into geometric
lines that look like someone spilled a box of toothpicks or needles on the
ground and they froze there.
Glaciologist Jeff Kavanaugh says the phenomena are due to
supercooled water — water that remains liquid below its normal freezing point being moved and rolled by wind as it begins to
solidify.
The round stone-like shapes are actually known as slush
balls "a very poetic name, I
know," he said with a chuckle.
They are the rarer phenomenon of the two so much so that Kavanaugh, an associate
professor in earth and atmospheric sciences at the University of Alberta, has
never experienced them in person.
"It's something I would definitely like to see,"
he told host Marcy Markusa in an interview with CBC's Information Radio on
Tuesday.
The ice anomalies were spotted on the weekend by Peter
Hofbauer, who owns Steep Rock Kayak and Canoe on the eastern shore of the lake,
about 200 kilometres northwest of Winnipeg.
He took photos and posted them on Instagram with the simple
question: "Have you ever seen the lake freeze like this?"
The post has been liked and shared hundreds of times, with
many people calling the formations beautiful, amazing and fascinating.
"Nature is incredible and so are these pics,"
another person posted.
Hofbauer told Markusa he was kayaking exactly seven days
before he took the photos.
After doing some research about the ice shapes, he found a
certain set of conditions had to come together at the right time rapidly cooling air temperature, open water
close to being frozen and the right amount of wind.
"The water created these balls of ice and they just
accumulated against the shore, and it seemed to just spread out over the lake
as far as I could see," he said.
According to Kavanaugh, that's exactly right.
There has to be a brief window where the water is open but
also cold enough at the surface that these slush balls can form from wave
action.
"If it's windy enough to to whip up the water, there
can be droplets that pop into the air and freeze and fall back as ice," he
said.
"And if there's enough wave action from that wind,
instead of forming the pancake ice, those pancakes are broken up, and they roll
around in the waves and form these slush balls."
Curious about the underside, Hofbauer went out Monday night
and cut out a section to look at the bottom, which was much smoother. But he
noted shortly after they were removed from the mass, the balls turned into
snow.
"That's why they call it slush balls," said
Kavanaugh. "They're very much like if you took a snowball — a weakly
compacted snowball … and put it in water. They're pretty delicate."
As for the stick-like formations, each of which was about
eight centimetres long, Hofbauer found those along very thin ice at the shore.
Those are again formed again by supercooled water but with
less wave influence, Kavanaugh said.
"In a calm condition, the water molecules can arrange
themselves into these crystals and they tend to grow like needles. You'll see
this sometimes in puddles on the sidewalk after a rain and then the following
cold snap," he said.
Unaware of the less-than-scientific name for the round slush
balls, Hofbauer created his own Latin name for the phenomenon: Cryolapidarius
maritimus, which he says means "stone formations that are cold from the
sea."
"Yup, a much better name than slush balls,"
Kavanaugh agreed.
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