James Nye — Daily Mail Jan 5, 2014
While America collectively freaks out over their impending ‘polar vortex’, Canada is changing the game when it comes to cold weather phenomenon as reports of ‘frost quakes’ emerge from around Toronto and across Ontario.
Indeed, as temperatures drop overnight to around -4f around the city hundreds of people are being startled by hearing large booms – causing them to think their homes are being broken into or gunshots are being fired.
In fact, they are merely hearing the after-effects of the frost quakes – or cryoseism – which are more commonly found on a glacier in the polar regions.
The phenomenon is caused when rain and ice seep down into the soil and then freeze when the temperature drops.
‘Water expands when it freezes and when it expands in frozen soil it literally puts a lot of stress on that dirt and will release that energy all of a sudden, very much like an earthquake releases that energy and shifts the ground,’ said meteorologist Natasha Ramsahai to City News.
Most frost quakes occur after a heavy rainfall or snow fall when there is a large amount of moisture on the ground.
‘We had the ice storm or freezing rain event, then we had warm temperatures, or just about freezing at the surface. Then the temperatures plummeted after that,’ said Dayna Vettese, a meteorologist with the Weather Network.
‘That’s why we’ve seen a couple of these events between the ice storm and the beginning of 2014.’
Around Toronto just after Christmas there was a thaw after some heavy snow fall that allowed ice to accumulate under the soil.
The subsequent deep freeze has turned that water to ice and caused the booms as giant chunks of the ground tear apart.
‘It’s almost like an earthquake because it’s very close to the surface. You will feel a little bit of shaking, maybe if you’re sitting in a chair and it happened, or you’re lying in bed, or some of your dishes might rattle,’ said Vettese.
Social media lit up over the weekend as hundreds of people experienced the rattles, bangs and grumbles caused by the frost quakes.
However, while unusual for southern Canada, frost quakes are definitely the norm in the north of the notoriously cold nation.