Just days after a massive ice storm hit the Greater Toronto Area (GTA), Christmas Eve ice quakes hit the area. The first reports of the loud booms hit Twitter feeds right around dinner Eastern Time, and the tweets peaked in numbers around midnight. Ice quakes were later reported being heard as early as 2 p.m. and as late as 1 a.m. Christmas Day morning.
The loud sharp-cracking booms were first thought to be sonic booms from comets or meteors entering the earth’s atmosphere hitting Toronto, Ontario or the Great Lake states. However there were no reports filed from the American Meteor Society ruling out comets and meteors as a possible cause. Earthquakes were also ruled out as the United States Geological Service did not register any Ontario seismic events on neither Christmas Eve nor Christmas Day, leaving an ice quake as the most likely cause.
An ice quake or frost quake is known as a scientific phenomenon called a “cryoseism.” Cryoseisms are caused during the start of a cold-snap by rapidly declining temperatures that suddenly freeze the groundwater. When water freezes it expands and the soil and rocks will split or crack. These cracks will release bursts of explosive energy that result in a kind of concussion wave of a loud sonic-like boom and also cause localized ground shaking. The phenomenon is more likely to occur after midnight and before dawn, when temperatures are most likely to be rapidly declining.
Even though cryoseisms are quite rare, they seem to occur more often in Ontario and the states bordering the Great Lakes. Sadowa, Ontario reported 12 cryoseisms on January 18, 2000 within two hours when temperatures neared -4 Fahrenheit or -20 Celsius.
The Northeastern U.S. states have had numerous reports of cryoseisms. Maine, Connecticut, Massachusetts, Vermont, New York, Indiana, Wisconsin and Ohio have all reported frost quakes in the past. Some of the earliest reports are of ice quakes in New England on February 5, 1908. An event in Danbury, Connecticut had residents awakening one morning to find cracks and fissures in a few of their streets.
Some of the latest reports in the U.S. are from 2007 in Ohio and 2011 in southwestern Ohio and Indiana.
Although they often mimic a seismic earthquake, the mostly mild tremors usually don’t usually cause any damage or injury.
Temperatures just north of Toronto were very chilly on Christmas Eve which likens the fact that what residents felt and heard were cryoseisms. Sutton, Richmond Hill, and Newmarket, all reported temperatures on Christmas Eve of -20 C or colder.
Many areas around the Great Lakes had recently been hit with an ice storm just a few days before Christmas Eve. The storm created much damage in the areas hit snapping limbs from trees and weighing wires and cables down past their limits. The ice storm coated everything in the region under a sheet of ice and up to 115,000 people have spent Christmas without power.
Neighboring provinces and states have been sending hydro workers to Ontario to help restore power to the many. The province of Manitoba sent 42 hydro workers to Toronto on Christmas Eve. The workers are planning on staying to help restore the downed lines until January 6th. Mayor Rob Ford stated that 100 hydro trucks and workers were also being sent from Ottawa, Windsor, and Michigan.
There have not been any more reported ice quakes in the Toronto area since the Christmas Eve events.
By Brent Matsalla