It has been a cold winter. Parts of the United States that usually stay warmer at this time of year are experiencing extremely cold air and a lot of snow. Besides the snow we also get frost.
Frost is formed when a solid surface is chilled below the dew point of the surrounding air. The surface is also colder than freezing. Tiny spike-like particles of ice then grow out from the surface making frost.
Precipitation is water that falls from the sky. It might be in the form of rain, snow, sleet, or hail. Eventually that water is absorbed by the ground to replenish the earth's water supply. So there are veins of moisture in the ground. Some are quite large while others are no more than little spider veins.
Water expands when it freezes. In the good old days a bottle of milk left by the milkman on the back step would freeze. The milk would rise as it froze and lift the little cardboard topper right off the bottle. That was why it was so important to get the milk in as soon as possible.
The water in the ground freezes in the winter too. The closer it is to the surface the more quickly it freezes. The colder the weather and the longer it lasts, the deeper the frozen water in the ground will be.
Occasionally the frozen ground water swells so much that it needs more room. The result is a loud explosive sound. Some people compare it to thunder, fireworks, or even bombs. The ground will shake similar to when there is an earthquake.
This action is called a cryoseism. They have measured as high as 1.5 on the seismograph, the same machine used to measure earthquakes. As a matter of fact it is hard to tell the difference between a cryoseism and an earthquake. The conditions of the ground and the surrounding weather are used as a guide.
Sometimes the frost quakes cause serious damage. Fissures in roads and cracking of building foundations are only two examples.
With the cold we are experiencing this winter there have been numerous reports of frost quakes. Illinois, Ohio, New York, Connecticut, Maine, and other states in that area of the country are where they occur. Canada also has frost quakes. There have been multiple reports of frost quakes in Toronto this year.
If you hear noises that sound like someone throwing snowballs at your house; if you see little flashes of light; if the earth shakes a bit now you do not have to be afraid. It might be nothing more than a frost quake.
hope I stay safe, been in a few real tremors out west
ReplyDeleteWith the weather we have been having you just do not know what to expect next.
DeleteWow...it makes sense but isn't something I have really though about....Living in the UK we don't get weather extremes like you so are less likely to suffer from these. I remember the milk freezing and coming out of the top of the bottle as a child...I always liked to pick it off and eat it as it was pure cream and tasted great""
ReplyDeleteThe frost quakes and ice quakes only happen in parts of the United States. I have never heard either one myself. It is an intriguing concept. I remember Mom being so upset when she did not get the milk in the house in time.
DeleteThis was really interesting. I never would have guessed this process could be measured on the Richter scale. Wow!
ReplyDeleteI love learning new things. I am always amazed at how much I do not know.
DeleteI read something knowledgeable but some how, I wish the earth's weather be it in temperature or anything else wont change but it is never a reality. The weather has changed too much over the few decades and in future, doubt what it becomes. In my country, there is never such a phenomenon.
ReplyDeleteWeather conditions happen in cycles. We warm for a bit then we cool off for a bit. It keeps life interesting.
DeleteA happy new year to all at Nature Magazine, may you have wonderful times in our beautiful wild landscapes!
ReplyDeleteThanks for sharing.
ReplyDelete