Frost Quakes Shake Toronto Homes: Sounds Like Someone on Roof, in Attic

Frost quakes occur when the temperature suddenly drops, causing groundwater to freeze. The water expands and cracks under pressure, causing explosive booms. The effects are so localized, one house might feel the effects, while a house a block away might not.
Frost Quakes Shake Toronto Homes: Sounds Like Someone on Roof, in Attic
(Shutterstock*)
Tara MacIsaac
1/4/2014
Updated:
1/5/2014

TORONTO—I was sitting at the kitchen table at my mother’s house just outside of Toronto, Canada, on Christmas Eve, when I heard a loud bang on the ceiling. My mother was in the adjoining living room watching television and we both started, thinking my stepfather had fallen upstairs. The bang shook the ceiling. 

My stepfather rushed down the stairs and asked what had happened. He hadn’t fallen. In the aftermath of the recent ice storm, trees were still falling in the neighborhood. We went outside to check, but everything was clear around the house. 

I said, “It must have been Santa.” I felt like I was in some Christmas movie. Of all the nights to hear an inexplicable bang, which seemed to come from the roof, it had to be Christmas Eve.

A few days later we heard a similar boom in the middle of the night. I recalled creepy stories I'd read of people discovering someone living in their attic. I wondered if we should maybe get up there and check just in case. Was it that someone fell in the attic? 

It turns out I wasn’t the only person in the Greater Toronto Area (GTA) having these thoughts. Reports soon popped up across the city, and the police received many calls from people describing things going bump—or in this case, bang—in the night. 

Meteorologists have provided an explanation: frost quakes have created small, localized tremors and loud noises. 

Frost quakes occur when the temperature suddenly drops, causing groundwater to freeze. The water expands and cracks under pressure, causing explosive booms. The effects are so localized, one house might feel the effects, while a house a block away might not. 

 

*Image of ice on grass via Shutterstock