Thursday, February 03, 2011

Thurs-demo: The one with the flasks of evaporating water

Okay, so this has always bothered the dickens out of me. People who point to heavy snowstorm events as some kind of "proof" that Earth's climate isn't getting warmer. The simple fact is: heat energy is required to put water molecules into the air (as water vapor). The warmer the water, the faster it will evaporate. The warmer the air, the more moisture it can hold. When warm, moist air from the gulf meets cold air out of northern Canada, the precipitation that falls out will be snow. More moisture available equals more snow.

This week's demo is simple, but illustrates this point - warm water evaporates more quickly than cool water. A warming earth dumps a lot of heat into the ocean. This warmer water then puts a lot of water vapor into the air. In winter, despite a warmer climate, heavy snow can fall.

Warm Water Evaporation from Matt Kuchta on Vimeo.



Granted, 0.2g of water evaporated doesn't really look all that impressive - but the temperature difference wasn't very big either. So one could easily "upscale" the demo using wide-mouth buckets or something that will present a large surface area to the atmosphere and evaporate even more water.

I'm all for discussion and reasoned debate over the mechanics of climate and the resulting weather patterns. But arguments based on easily falsified misconceptions are just plain dumb.

1 comment:

  1. I see myself using this as a lab in my climatology course this fall....

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