Frigid Temperatures Trigger Rare “Frost Quakes” in U.S. and Canada

Frigid temperatures can cause frostbite, but they can also trigger little-known underground explosions called “frost quakes.” These quakes are a rare weather phenomenon that has been reported with surprising frequency in the past week. Frost quakes, or cryoseisms, occur in the winter, when a warm spell allows rain or melting snow to seep into cracks and crannies in the ground. When a cold front suddenly hits (like the polar vortex smacking much of the U.S. and Canada at the moment) that water quickly freezes. As it freezes, the water expands and outgrows its small underground space, cracking the frozen soil or bedrock around it to make room.