In case you missed the memo, it's really, really cold outside in large parts of the country. When it gets this cold (colder than Mars!), the Earth itself can start to do some really strange things. Up in Canada, some residents of Toronto were woken up by what sounded like sonic booms coming from the beneath the ground.
A frost quake is caused when rain and ice seep down into the soil and then freezes when temperatures drop.
“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 Ramsahai.
Frost quakes aren't related to earthquakes, despite their similar names. But, frost quakes can be picked up by seismic wave monitors.
Frost quakes, also known as cryoseism, can start to happen when the temperature gets down to around -4 F, says Natural Resource Canada. So, as cold temperatures continue to grip the land over the next few days to weeks, keep your ears tuned to the sounds of the Earth.
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