The science of snow, and how to deal with it
Science blogger Julian Taub makes living with snow and ice a little easier.
Wed, Jan 04, 2012 at 03:17 PM
We all enjoy the winter wonderland that nature provides us with each winter. Well, except when it’s covering the driveway. Regardless of how serene and beautiful it looks, snow can be a pain to deal with, literally. Knowing a few facts about snow can help you deal effectively with this fluffy winter pest.
Snow is made out of dust particles that freeze in the clouds. When snow hits the ground, it is mostly made up of ice, air bubbles and water vapor. The density of the snow (how heavy it is) depends on how much water the snow contains altogether. The more “water content” in the snow, the harder it is to shovel. Old packed snow is the worst of them all; you can barely get your shovel into it.
Despite the fact that snow is less dense than water, shoveling snow can be a major strain on the body. In cold weather, the body’s blood vessels constrict to hold onto whatever heat it can. However, the heart and lungs have to work even harder to pump oxygen to the lungs. Coupled with lifting pounds of snow every 10 to 30 seconds, it is very easy to pull a muscle or become out of breath. It can even become life threatening to someone prone to heart attacks. Remember to always stretch beforehand, pace yourself, and use a shovel that matches your body type.
Forget melting snow with a heater. It doesn’t work all that well and you can waste a lot of energy. Because of the air pockets within snow crystals, snow is a very good insulator. Heat doesn’t travel well through a snow mound. Moreover, when snow does melt during winter, a new problem arises. The leftover water from the melted snow usually turns into ice. The surface of ice has a microscopic layer of water that allows the ice to be slippery. Also, the water molecules in the ice both bond tightly to each other when frozen and bond to the molecules of the ground below. This makes it excruciatingly difficult to scrape off and remove.
The best mode of snow removal and ice removal is using a deicer. They are usually made out of some kind of salt that is absorbed into the ice or snow. Water has a lower freezing point when something is dissolved in it, making sure the ice and water mixture melts and cannot freeze again. Three of the most used deicing chemicals are table salt (sodium chloride), calcium chloride, and magnesium chloride. Unlike table salt, the calcium and magnesium chlorides also give off heat when they mix with water, helping the melting process. However, salts can damage plant life, badly made concrete (concrete that has air bubbles in it) and metals, like steel and aluminum. This is especially true with magnesium chloride, which can change the chemical makeup of concrete and harm electrical appliances. CMA, a chemical made of calcium, magnesium, and vinegar is a noncorrosive and safe alternative for deicing. Still, as a precaution, check the quality of your concrete and rub alcohol around metal surfaces to lower the freezing point of the ice on them.