Cold snaps such as the recent arctic blast of Jan. 5-8, 2014, can bring a different kind of cold snap -- the loud boom of the earth from frost quakes.
The quakes, known as cryoseisms, are a natural phenomenon caused from a sudden deep freezing of the ground. They occur near the surface of the earth and result from freeze-and-thaw cycles which weaken and break rock due to high water pressure, according to Natural Resources Canada.
The frost quakes were recently reported around Toronto and Brantford, Ontario, and Illinois, Indiana, Michigan, Ohio and Wisconsin during recent cold waves, including a rare appearance of the polar vortex in the U.S.
Residents reported loud booms and cracking sounds from the frost quakes.
Loudest boom yet about 35 minutes ago. Sounded like a small bomb going off. Why have we never heard of these before now?#weather #icequake— Linda O'Connor (@loconnor57) January 7, 2014
The frost quakes have nothing to do with earthquakes. Movement of tectonic plates, volcanoes and other factors are unrelated to surface temperature, Natural Resources Canada said.
There is no such thing as "earthquake weather," with an equal distribution of earthquakes in hot, cold, hot or rainy weather, the U.S. Geological Survey said.
Frost quakes usually occur between midnight and dawn, the coldest part of the night, the Maine Geological Survey said. They can occur over several hours and even several days.
Water from snow and rain froze rapidly in the ground when the arctic cold front rolled through the Midwest and Northeast and caused the ground to expand and crack in places, AccuWeather Meteorologist Randy Adkins said.
"With the rain, it didn't have a chance to soak deeper in the ground before it became extremely cold," Adkins said.
Another cold spell is expected this week but it will "not be remotely close to that cold outbreak," he said.