Frost Quakes Reported in Chicago, Startling Residents with the Loud Pops

Residents in Chicago recorded hearing several frost quakes last week, known in scientific circles as a cryoseism. These sudden loud booms are often mistaken for earthquakes due to the combination of the sound and the movement that it triggers.

What is a frost quake and why do these frost quakes happen during cold weather? Read on for more about this unique weather phenomenon.

Diving Into the Science of a Cryoseism

A frost quake is a unique weather occurrence that happens during times of extreme cold temperatures. These cryoseism events have been recorded in the U.S. since the early 1800s even before people understood why they were happening. The word "cryo" comes from an ancient Greek word that translates to icy cold while the word "seism" translates to a violent storm.

Scientists explain that a frost quake happens when ground that is overly saturated quickly freezes shortly after a time period of mild weather. The movement of water expanding when it freezes works to push apart the soil and rocks. A rapid expansion of the ground in turn triggers the breaking apart of the earth, leading to the sound boom and the sensation that is reminiscent of an actual earthquake.