Global Warming

There are a couple of key questions in the global warming debate. I am not a paleoclimatologist, so I am hardly qualified to speak about the mechanisms and history of the temperature of the earth. The question is, are they?

Things we need to know, and seperate from each other:
1) Is the earth warming up? This can be observed from current data. Recent years do seem warmer than previous years, but this is with no more than about a couple-hundred-year window.

2) Does this warming deviate from the long-run history of the earth? This is a crucial question. More below.

3) Is any deviation from long-term trends due to human activity? Another point suspected, and modeled, but I have heard that said models are somewhat shaky. The Earth is really frickin' complex. To claim to fully know how X affects Y when a direct result cannot be observed is something that leaves me nervous.

More on Question #2. The U.S. House of Representatives committee on Energy and Commerce recently held a couple hearings on Global Warming. At issue is a temperature reconstruction done for the UN IPCC (International Panel on Climate Change) in 2001, and for an academic paper in 1998 that shows the temperature of the earth spiking to unseen heights in the 1900's, dating back more than 1,000 years. This would be significant. The problem is that the statistical methods used to do the reconstruction appear (1) not to have been worked on with any statisticians, (2) to be fundamentaly flawed - intentionally or unintentionally - in a way that predicts the end result whether the historical data or even random data is inserted.

An independent panel was comissioned to look into this. Their results are worth looking at. A website I read regularly has put together some of the excerpts from the first hearing on the subject. The attitude of the Democratic congressmen seems to be this: "We know the truth, don't bother us with your facts. Your facts might run counter to the Truth. You are here not to address the Truth, but to satisfy a partisan agenda. You are hypocritical in your analysis of the Truth." I was shocked to read some of these statements.

I prefer the report the most. Written by a statistician who voted for Gore, I trust it to be less partisan. The key issues brought up are (1) The statistical tools were misused, (2) the academic review of the work was done with people the authors knew and collaborated with on other papers, instead of independent experts, and (3) No experts in a key field (statistics) were consulted, despite multiple authors being from schools with excellent stats departments.

Excerpts Here
Full Report Here (PDF, 1.4 MB)
Committee Page Here