Thursday, December 6, 2012

Weather Mythbusters, 2nd Edition

Time to clear up some more weather myths out there. Today's theme will be (mostly) about lightning but we will kick off this edition with a snow myth. We are heading towards winter, after all!

Myth: It can get too cold for snow?
Truth: While this is not common, it can occur. The basis behind this fact is rooted in the properties of the atmosphere at certain temperatures. Consider: In order for clouds to form and precipitation (in our case, snow) to occur, air on a large scale must rise through the atmosphere. Warm air is less dense thus more likely to rise through the atmosphere. Colder air is more dense so it has a tendency to sink throughout the atmosphere. Sinking air promotes high pressure which stabilizes the atmosphere making it less likely for precipitation to form. So if air gets too cold there just isn't enough precipitation in the air nor is there the dynamic properties to produce snow! We're talking COLD though, temperatures around -40 degrees Celsius.

Myth: Lightning doesn't strike twice in the same place
Truth: This is false. Lighting strikes the same place multiple times, all the time. Lightning rods were designed to do this very thing. They attract lightning strikes in order to keep bolts away from surrounding buildings and utility stations. Nothing occurs that prevents lightning from striking the same place twice.

Myth: The temperature of lightning is hotter than the surface of the Sun.
Truth: This, believe it or not, is true. In fact, air around a lightning bolt can heat up to a temperature of 54,000 degrees! Lightning results from a static build-up between the atmosphere and the rain/ice crystals in the storm. The release of this build-up occurs in the form of lightning. The bolt lights up the sky and heats up the air surrounding the storm. Heating the air to such high temperatures sends shock-waves through the air and the expansion results in thunder.

Myth: There can be lightning without thunder.
Truth: Yes, this is true, but only based on how far away you are from the lightning strike. Thunder reflects, bounces, and gets absorbed by the earth's environment. If you are a sufficient distance away from the strike, you may see the flash but the sound wave of thunder may be effectively scattered by the time it reaches you.

Myth: Rubber tires make your car a safe place in a thunderstorm.
Truth: There is a partial truth to this. Yes, rubber makes it safe-er to be in your car during a thunderstorm but it is actually the frame of your car that makes the car a safe place to be. The metal cage that surrounds your car will help absorb the lightning bolt should one strike your car.

Lightning is a powerful thing,

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