Tuesday, September 17, 2013

This is a bit funny, and tragically true

The five stages of climate denial, by Abe and Nucky:

The five stages of climate denial are on display, prior to release of the IPCC report

Yes, those who deny the climate is changing due to the activities of humans (predominantly) do all of these things.  My favorite is number 2, because it's technical and it also refutes a recently highly-circulated release of nonsense from Roy Spencer:

So here's a big massive quote, with big massive quotation marks.  I underlined a couple of points worth special noting.

"Stage 2:  Deny we're the cause

Once people move beyond denying that the problem exists, they often move to the next stage, denying that we're responsible. John Christy and Roy Spencer took this approach by disputing the accuracy of global climate models in The Daily Mail and The Christian Post, respectively. Spencer was quite explicit about this:
...we deny "that most [current climate change] is human-caused, and that it is a threat to future generations that must be addressed by the global community."
Christy and Spencer made their case by comparing the outputs of 73 climate models to satellite temperature measurements, and showing that the models seemed to predict more warming than has been observed. But the comparison was not of surface temperatures, or of the lowermost layer of the atmosphere, or even any measurement global average temperatures. They specifically looked at measurements of the temperature of the middle troposphere (TMT) in the tropics.

There's certainly nothing wrong with examining this particular subset of temperature data, but it's a bit of an odd choice on the face of it. The real problem lies in the fact that satellite measurements of TMT are highly uncertain. In fact, estimates of the TMT trend by different scientific groups vary wildly, despite using the same raw satellite data.

Another problem is that the stratosphere (the layer of the atmosphere above the troposphere) is coolingan expected consequence of the increased greenhouse effect. But some of the cooling stratosphere bleeds into the TMT data, leading to another cool bias. While there is a discrepancy between model simulations and measurements of tropical troposphere temperatures, it's not clear how much (if any) is due to the models being wrong, and how much is due to errors in the measurements. As a U.S. Climate Change Science Program report co-authored by John Christy concluded,
"This difference between models and observations may arise from errors that are common to all models, from errors in the observational data sets, or from a combination of these factors. The second explanation is favored, but the issue is still open."
However, in mainstream media interviews and editorials, Christy and Spencer always fail to mention the possibility that the problem could lie more in the measurements than the models, which frankly is intellectually dishonest. Additionally, climate models have done very well in projecting long-term global surface temperature changes."

Read the article to find out what the other four stages are.

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