Who is the mother of the ice? Who gives birth to the frost from the heavens? For the water turns to ice as hard as rock, and the surface of the water freezes. Job 38:29-30 NLT
Almost everything contracts when frozen. Water, (H2O), however, is one of the few substances that actually expands when it cools from a liquid to a solid. At about 39º F, water expands slightly. But at 32º F, water expands quite a bit, about 9 percent of its volume.
The fact that water expands when frozen is critical to life on earth. As water freezes and expands, it becomes less dense than in its liquid form. That is why ice floats on the surface of a lake or ocean, because it is less dense than the liquid form of water it is resting on. This actually helps to keep aquatic organisms that live under the ice, like plants, insects, and fish, etc., a bit warmer than freezing.
Think of it this way. If water became denser – more compact, like most everything else when frozen – then ice would sink to the bottom of the pond or lake or ocean instead of floating. The lakes and oceans could potentially fill up from the bottom to the top, destroying the aquatic life in the process. White polar icecaps would melt or sink. And these ice caps are vital for reflecting sunlight from the earth so that we can live in a climate that is suited for us.
There is a bit of chemistry and physics involved concerning how the hydrogen and oxygen molecules act and react to each other when water is changed from a liquid to a solid and back again. If you want to read a little about that, or about an exception where ice actually forms on the bottom of a stream, click on Anchor Ice. Suffice it to say, if water didn’t act differently than most other things when it freezes and changes from liquid to solid, life on this planet would be kaput.
The above photo is a picture of a rain chain hanging from a gutter over our porch. The frozen water enveloping the chain made for a bit of a unique picture. It also reminds me once again of how fortunate we are that there is an all-knowing God who designed our world to work in amazing ways. If you are not sure how to have a relationship with this all-knowing God, please see Got God?
Hope you have a great day.