Monday, December 14, 2009

 

An Important Regression


In high school we took a practical art/art history class senior year. It was a hoot. My best friend Frank Kelly and I couldn't draw a straight line, but we loved the art history part and did our best to memorize the famous paintings, etc. and the years they were produced. There was, one day, a remarkable series of slides shown by the teacher.

It was a big Bierstadt painting, but the slide series started with a detail of the painting, a pool of water with a turtle in it. The next slide pulled back a little and showed more of the painting, and on and on for about 20 slides until the whole painting, of the Sierra Nevada mountain range, was revealed. Frank, who is now a big wig in the National Gallery--specializing in American 19th C . landscapes--was seriously impressed and indeed his ultimate career path started that day, I believe.
I think the remarkable thing of the slide show was the constantly changing, expanding, frame of reference of the work.

So here is a similar ever expanding series of graphs from a glacier in Greenland which covers the past 50,000 and shows the temperature record therefrom.

The first graph, above, back just to 1400, about a 150 years after the end of the Medieval Warm Period, shows a hockey stick style graph, with a steep rise beginning about 1825. Ooh, scary.

But back up a little (to 900 AD) and the "blade" of that hockey stick is revealed as a tiny blip compared to the serious warming of the Medieval Warm Period. Back up, again to 3000 BC and even the Medieval Warm Period is dwarfed by other higher and more sudden warmings.

The little 1825-on "blade" of the first graph is revealed to be a very small version of many sudden rapid rises in temperature again and again and again.

Back up again to 9,000 BC and the start of the interglacial is a huge steep climb in temperature which reduces the 1825-on "blade" of the first graph to utter insignificance. Back to 50,000 during the depths of the latest ice age, and the interglacial is revealed to be the oasis one would expect. The final graph is the Vostok Antarctic ice core which takes the temperature record back to 400,000 BC and shows a series of ice ages with brief, warm interglacials in between. This is the same graph Al Gore used in An Inconvenient Truth to show a congruence of CO2 and warmth (of course Al neglected to show that the warmth preceded the rise in CO2 by an average of 800 years). To a disinterested viewer, the final graph shows that the little bit of warming since 1825 is absolutely within the norm of ancient warmings, indeed it is dwarfed by most of them, and there is nothing, NOTHING, special or even slightly alarming about the recent climate change. Since the rapid big warmings over the past 400,000 years were clearly before any industrialization or the burning of fossil fuels, there appears to be nothing in history which would cause us to believe that recent warming is anything new, and certainly nothing alarming.

With the correct frames of reference, our modest recent warming is reduced to mere background noise in the constant flux of mean temperature. It is reduced to nothing at all.

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