Tuesday, March 20, 2007

Averaging Problems

The problem with "Averaging" temperatures over a large area, is that is does not give you a clear picture of anything. Today we learned that this winter tied the second warmest Canadian "average" on record. What the hell does that mean? It means that some places in Canada where indeed warmer than "average" this winter. What it does not tell you is that some of Canada was colder than "average" as well. Canada is not in a bubble, where the temperature is spread out evenly throughout so an "average" temperature means nothing. Knowing that it was warmer in the Yukon does not do a thing for the prairie farmer when his cattle are freezing to death in central Alberta. Local weather is influenced by many factors, too many to calculate accurately. That is why a professional meteorologist has a hard time predicting what the weather will be in the next couple days never mind weeks, months or years in advance.

Lets move this topic up a notch to global "averages", instead of just Canadian "averages" shall we. Although one can argue that the earth is indeed in a bubble of sorts, and that the global "average" does effect the planet as a whole, it still does not disperse the temperature evenly throughout. Again an "average" global temperature does not give a clear picture of anything. Some places are cooler than average and some are warmer. The "average" may be warmer or cooler during any given period. We are currently going through a "average" warming period. 30 odd years ago we were going through an "average" cooling period, and before that a warming period, and before that a cooling period. Our weather is in a constant state of change. Locally we go from spring to summer to fall to winter and back to spring again on a yearly basis. Globally, the earth does a similar thing over a longer period of time. It is nature doing one of its balancing acts that it is required to do on an ongoing basis.

Science Daily Researchers Question Validity Of A 'Global Temperature':

"It is impossible to talk about a single temperature for something as complicated as the climate of Earth", Bjarne Andresen says, an an expert of thermodynamics. "A temperature can be defined only for a homogeneous system. Furthermore, the climate is not governed by a single temperature. Rather, differences of temperatures drive the processes and create the storms, sea currents, thunder, etc. which make up the climate".

He explains that while it is possible to treat temperature statistically locally, it is meaningless to talk about a a global temperature for Earth. The Globe consists of a huge number of components which one cannot just add up and average. That would correspond to calculating the average phone number in the phone book. That is meaningless. Or talking about economics, it does make sense to compare the currency exchange rate of two countries, whereas there is no point in talking about an average 'global exchange rate'.

If temperature decreases at one point and it increases at another, the average will remain the same as before, but it will give rise to an entirely different thermodynamics and thus a different climate. If, for example, it is 10 degrees at one point and 40 degrees at another, the average is 25 degrees. But if instead there is 25 degrees both places, the average is still 25 degrees. These two cases would give rise to two entirely different types of climate, because in the former case one would have pressure differences and strong winds, while in the latter there would be no wind.


You can think globally all you want, but when you boil it all down, the only thing that really matters is local. Do I need to bundle up to go to work today or can I scare the hell out of everyone in my speedo?

6 comments:

ABF said...

Damn ... I never thought I'd be praying for cold... the thermodynamics generated in a speedo belong on Bellamy hill.

Tim said...

I see it this way AB.... if certain women are allowed to wear spandex.... I can wear a speedo! I am a sexy fat bastard!

Candace said...

Good call! and f*ck the average, I say, give me some damn warming already.

Tim said...

You just want to see me in my speedo don't ya Candace!...;)

ABFreedom said...

I could say "Get a room" .. but I really don't want to say anything like that... LOL

Tim said...

I have several rooms AB...what you talking about?.... :p