Thursday, February 11, 2010

Local weather versus global climate

According to Treehugger: The Utah House of Representatives just officially called Anthropogenic Climate Change a conspiracy. From their page:

It (obviously) continues further, but it's all in an effort to try and persuade the USEPA to not regulate carbon dioxide as a greenhouse gas.... because officially calling a duck an eagle - and making laws to ensure that this happens - doesn't change the "duckness" nature of the now-eagle (if it looks like a duck and quacks like a duck, then it's an eagle in Utah).

This seems to be a general movement that is taking place on the political "right" - Global Warming isn't happening, and where is Al Gore to eat humble pie? Luckily (and happily for me), MSNBC's Rachel Maddow brought on Bill Nye "the Science Guy" to explain why lots of snow in DC is actually what AGW predicts, and why a local phenomenon cannot be extrapolated to the world:

I like how the usually calm and jovial Bill Nye get's really angry at AGW denialists who (I thinke) he believes are actively and cynically lying to people and calls them unpatriotic and treasonous.

However, if you can't watch the clip, then basically, the science that Bill Nye discusses is that two things are happening this year: 2009 was globally one of the warmest years on record. This means that oceans are warmer (i.e., they have more thermal energy). Due to their higher thermal energy, more water is able to evaporate from the oceans, leading to greater amounts of humidity in the air, which leads to heavier snows. Add to that the El Nino/Southern Oscillation (ENSO) effect - 2009 was an ENSO year - that normally plays havoc with North American winter weather, and it's not unexpected that the East Coast is suffering from snows. All the calls of "tell your congressman how many inches of global warming you've received" is actually accurate: AGW can cause more snow. If the temperatures during the winter remained above freezing, then it would have been a lot of rain, but guess what? A couple of degrees of warming isn't going to push winter temperatures in DC above freezing all too often, so those storms are gonna (due to phase shift) come down as frozen water: snow!

Interestingly (or maybe strangely), the right-wing zealotry over the message of "it's snowing a shedload over the Eastern United States, therefore AGW doesn't exist" actually got The Daily Show to cover it (well, that an the fact that it's based in NYC, where there was a shedload of snow):

The Daily Show With Jon StewartMon - Thurs 11p / 10c
Unusually Large Snowstorm

Daily Show
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I really like how the Best F*cking Weather Team is able to show - through sarcastic satire - how disingenuous is extrapolation of local and short-term conditions (i.e., your weather outside your window) to global and long-term conditions (i.e., global climate). I also wrote about the difference between climate and weather and short-term versus long-term, but not with anywhere near as much pizazz as The Daily Show or Rachel Maddow.

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