Wacky winter weather
‘Frost quakes’ shake Ontario.
TORONTO — The extreme cold is leaving Toronto with a bang rather than a whimper as residents around the GTA report loud booming sounds in the night that may be caused by “frost quakes.”
People reported noises loud enough to wake them up as temperatures dipped below - 20 C. The booms occur when moisture in the ground freezes and expands, putting pressure on rock. This pressure is ultimately released with a loud boom as the rock cracks.
According to the Maine Geological Survey, the phenomenon is also known as cryoseisms. The agency calls it “a literal ‘ cold snap’” and describes the sounds variously as a “deep rumbling” that sent windows shaking, a “shudder” and a cracking sound.
Mike Leibovitz said at least four frost quakes hit his house last night, with the strongest one at around. 2: 30 a. m.
“To be honest, we literally thought that our roof broke or something. Our house pretty much shook,” he said.
“It was pretty loud. I mean, the two of us woke up out of deep sleep, it woke my daughter up. It definitely was a boom and my house, my roof was shaking.”
Paige Kruger described similar banging sounds around her house.
“My dad was like walking around the house to see if anyone broke in,” she said.
“Then it sounded like somebody was basically banging around in the walls of our house.”
The sounds have been striking in the night, usually between about midnight and 5 a. m.
Allison Bent, a seismologist with Earthquakes Canada, explained how the “frost quakes” felt similar to earthquakes but were caused by ice.
“What they are is cracking of ice or two blocks of ice moving one against each other. It happens because ice expands when it gets cold,” said Bent.
“So it often happens when it’s extremely cold, like - 20 or colder and particularly if there’s been a sudden drop in temperature, and especially near lakes and rivers.”
It feels a lot like an earthquake to someone close to it, but Earthquake Canada’s instruments don’t pick up the shaking since these ice quakes are very localized, according to Bent.