On Friday I was pointed to another Internet posting that purported to show that the recent warming is due to changes in the PDO. It was probably based on the writings of D’Aleo at Icecap. I’ve written before that the PDO cannot contribute to global warming for the simple reason that for the ‘classical’ definition of PDO, the trend is removed (eg, at the University of Washington). There will still be variations about the mean, and those variations may mask or enhance the global warming signal in the global mean surface temperature, but it cannot contribute to a trend.

This post was originally just going to be a short rant about not understanding the definition of PDO and its implications. But as I was making some figures to include with this post, it began to evolve into something different. The ‘classical’ definition of PDO excludes any trend in the data. But what would happen if the trend were not excluded? How would that influence the shape of the PDO time-series and its corresponding EOF (empirical orthogonal function; basically, what the PDO looks like in space instead of time)?
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This story hit the newsstands almost two weeks ago, but it’s an important one I think. Sky islands are chains of mountains that are isolated in valleys. I’m sure most everyone is aware that as you go higher in elevation, the temperature decreases. Snow-capped mountains are a good example of this. But how much does the temperature change with height?

Wikipedia offers a definition of the dry adiabatic lapse rate. I’ve not seen it written like that before. I only recall seeing it as Γ=g/cp. In either case, the temperature decreases by about 10C for every kilometer you go up in altitude. As an example, I live in Tucson and it’s hot. The forecast for Tucson is 99F for today.
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Just a quick link to a good post - Science After Sunclipse: What Science Blogs Can’t Do.

First off, I’m not an economist. I took one undergraduate-level macroeconomics course. And I did stay at a Holiday Inn last night. Therefore, I judge myself to be fully qualified to be admitted as an expert witness in economics. Luckily, the topic of today’s post is simple, and if I misuse any real economics buzz words, I ask that you politely point them out instead of chopping off my head.

When assessing the total cost of an automobile, there are two main areas categories: the initial investment and recurring costs. Figuring out the initial investment is easy; it’s the price on the window. The recurring costs are more difficult, and depend on how much a person drives.
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