By Kristina Kassis (Fall 2012 GE 101 student)
Have you ever been jarred awake in the middle of a particularly cold night by what seemed to be a small earthquake? If you have, chances are that it was not an earthquake but rather a rare frost quake, also known as a Cryoseism.
Frost quakes are non-tectonic seismic events that are caused when a sudden drop in temperature induces the freezing of groundwater, which expands and then cracks under pressure. This crack may be explosive, resulting in loud noises and movement of the earth, similar to what occurs during a small earthquake. However, unlike earthquakes, which have effects that can be very widespread, frost quakes have extremely localized effects: a family in a house might feel a frost quake, while a family merely one street away may not feel the ground move at all.
While frost quakes are a rare phenomenon, there have been a number of cases reported in the Northeastern United States in the last century in places such as Ohio, Wisconsin, Indiana, upstate New York, Vermont, Massachusetts, Connecticut, and Maine. In some of these cases, people were actually able to find a small fissure in the ground at the point where the Frost quake originated.
Frost quakes have been reported across New England as far back as the early 20th century. In 1908 it was reported that a frost quake occurred at four different locations in New England on February 5. In Danbury, Connecticut, for example, the headline of the local newspaper read Earth Tremors Due to the Extreme Cold. The article continued, “The event in Danbury left large fissures in several streets in the early morning hours. Other locations feeling a frost quake were Portland, Maine; Nashua, New Hampshire; Nyack, New York; and Brockton, Massachusetts. Several Portland residents reported their houses shaken by the event.”
On January 30, 1994, residents of West Berlin in Wisconsin were frightened by what they believed to be an earthquake. The startled residents reportedly experienced loud noises “like explosions” and violent ground tremors. Ron Friedel, the curator of the University of Wisconsin-Milwaukee’s seismograph station, attributed the event to a frost quake resulting from changing temperatures. Again, no damages or injuries occurred as a result of the quake.
Another substantial frost quake occurred during the early morning hours of February 10, 2011. During the night, temperatures had fallen well below freezing in some areas across Central and Eastern Indiana and into Western Ohio. These icy conditions were ideal for a widespread outbreak of frost quakes. Residents of the area reported that they heard loud explosions reminiscent of thunder and felt tremors similar to an earthquake that supposedly persisted for over 8 hours. They were understandably frightened by this event and quickly reached out to local media and government agencies for an explanation. Their answer: a frost quake! Thankfully no damage or injuries occurred.
The large Frost quake felt in Indiana and Ohio in 2011 is only one example of many frost quakes documented all across New England and other parts of the Northeastern United States in the past century. Perhaps the best-documented frost quake in history occurred during the early afternoon of January 31, 2008 at Madison, Wisconsin. This frost quake was especially surprising because they usually occur between midnight and dawn, during the coldest part of the night. At around 12:50 p.m. however, tremors around Lake Mendota that persisted several seconds registered on a seismograph in the University of Wisconsin-Madison Geology Department.
Seismologist Cliff Thurber, who saw the quake’s effect on the department’s seismograph, was struck by this event. Thurber hypothesized, after observing a large shift of ice on the surface of Lake Mendota, that a sudden drop in temperature was responsible for the tremors. Thurber later noticed a new large visible break in the lake’s surface ice, supporting his hypothesis that the icy conditions had caused a Cryoseism.
There is little scientific data pertaining to frost quakes. Michael Hansen, director of the Ohio Seismic Network, said the recipe for a frost quake requires “a sunny day that helps thaw ice and snow, followed by a quick freeze.” Beyond that, he said, very little is known about what causes frost quakes to occur in some regions and not in others. “These things are really poorly understood,” he added.
While frost quakes may be misunderstood, they are not dangerous. In no cases of frost quakes reported were any damages or injuries incurred.
So next time you find yourself abruptly awoken in the middle of a cold night by tremors in the earth, do not be alarmed: Mother Earth merely has a case of the shivers.
 Heidorn, Keith C. PhD. “Weather Almanac for March 2012: Frost Quakes.” The Weather Doctor. N.p., 01 2012. Web. 1 Nov 2012. <http://www.islandnet.com/~see/weather//almanac/arc2012/alm12mar.htm>.
 Hunt , Spencer, and Meredith Heagney. “Cyroseisms: a Case of Mother Earth’s Cold Shivers, and not and Earthquake: A Watchman’s Report.” . N.p., 12 2011. Web. 1 Nov 2012. <http://beforeitsnews.com/strange/2011/02/cryoseisms-a-case-of-mother-earths-cold-shivers-and-not-an-earhquake-a-watchmans-report-415211.html>.