‘Frost Quakes’ Are Now Hitting Chicago, That’s How Cold This Polar Vortex Is

It’s so cold in Chicago that the city is being bedeviled by what scientists are calling “frost quakes” – that is, loud booms caused by expanding ice underneath the ground.

A couple of days after a polar vortex rolled into town, bringing with it temperatures and wind chills plunging as low as 21 degrees below zero, the city is faced with a new problem: incessant loud booms. Chicagoan Chastity Clark Baker told WGN-TV (Chicago) she heard the sounds but didn’t know what they were.

“I thought I was crazy! I was up all night because I kept hearing it. I was scared and thought it was the furnace. I kept walking through the house. I had everyone’s jackets on the table in case we had to run out of here.”

Another user reported that he thought his furnace was about to explode.

In fact, the scientific reality behind what’s going on is no less terrifying. What’s happening is that the City of Broad Shoulders is experiencing what meteorologists call “frost quakes,” or more scientifically, “cryoseisms.” They only occur under certain conditions; specifically, the ground has to be saturated with water, a box which Chicago can easily tick from having been buried in snow from the two previous snowstorms that preceded the polar vortex. Then, the temperature plunges – in Chicago’s case, to negative 21 degrees – causing the water to freeze. The expanding ice then cracks, knocking loose the soil above, creating a loud boom.

Anyone who has experienced an earthquake and a frost quake can immediately point out the similarities, including the loud noise and the building-shaking rattling that follows. But, as the Los Angeles Times reported in 2014 when another polar vortex was punishing the Midwest, University of Toronto Scarborough Climate Laboratory researcher Andrew Leung reassured readers that frost quakes don’t cause damage like earthquakes. At least, not as far as he knows.

“Since frost quakes are rare, localized, cannot be monitored and tend to cause only minimal damage, the scientific community has very limited amount of information.”

Leung says that, in a theoretical sense, a frost quake could damage a building foundation or a road, but reports of that happening are rare.

Unfortunately, frost quakes are the most minor of the polar vortex-related problems bedeviling Chicago, and indeed, much of the United States. As of this writing, according to U.S. News & World Report, record cold temperatures have claimed at least nine lives across Wisconsin, Michigan, Minnesota, Iowa, and Illinois.