Sunday, August 28, 2011

Paul Krugman on Global Warming

I like Paul Krugman. I read most of what he writes and find him to be very bright and I generally agree with him. But I part company with him when he puts his "climatologist" cap on and pontificates as he has in his latest NY Times op-ed column:
The second part of Mr. Perry’s statement is, as it happens, just false: the scientific consensus about man-made global warming — which includes 97 percent to 98 percent of researchers in the field, according to the National Academy of Sciences — is getting stronger, not weaker, as the evidence for climate change just keeps mounting.

In fact, if you follow climate science at all you know that the main development over the past few years has been growing concern that projections of future climate are underestimating the likely amount of warming. Warnings that we may face civilization-threatening temperature change by the end of the century, once considered outlandish, are now coming out of mainstream research groups.

But never mind that, Mr. Perry suggests; those scientists are just in it for the money, “manipulating data” to create a fake threat. In his book “Fed Up,” he dismissed climate science as a “contrived phony mess that is falling apart.”
Krugman and I agree on holding Rick Perry in low esteem for his anti-science views. But I disagree with Krugman over global warming.

Take a look at this 130 year record of temperature anomaly data from NASA (note: "anomaly" means deviation from the average over the 130 year baseline):

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I don't see any "trend" and certainly no "runaway global warming" in the above graph.

OK... I cheated a bit. That is the continental US data. I trust that more than the global datasets because the network of stations in the US is thicker and is more likely to be monitored and calibrated better than measurements around the world. Also, the "world" is 3/4 ocean and there really are no stations gathering data there (sure some buoys and radiosondes that are occasionally dropped) like the coverage of the US. Here is the NASA global anomaly data:

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I prefer the following satellite temperature observations which uses the same sensor over the whole face of the earth. The only problem with satellites is calibrating the sensor and degradation of the sensor over time. But I trust the satellite more than I trust all the stations in the above "world" datasets (especially the “missing” stations covering 3/4 of the face of the earth, i.e. the oceans which aren't measured but "extrapolated" and sometimes for hundreds and even a thousand miles)

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To my eye, the above shows no discernible temperature "trend". Sure you can fit a line through the data and get a slight rise over time, but the signal is lost in the noise. I wouldn't trust that "trend".

The satellite is the most reliable, objective, global measure of "warming" and it doesn't support the purple prose of Paul Krugman:
we may face civilization-threatening temperature change by the end of the century
Neither Krugman nor I are climatologists. When Krugman cites 97% of "researchers in the field" believe in "global warming", I say so what? If you had canvased physicists in 1905 for a "belief" in warped space and time dilation you would have found 99.9% rejected the theory as preposterous. But Einstein's theory is true and is used every day in GPS systems and in the appropriate physics calculations. Science isn't a democracy where you vote on your favourite theory to establish its truth. It is consensus. But not a voting consensus. It is a hard fought consensus arrived at over time by experiment and working with the theory. Global warming isn't anywhere near that kind of "established" science right now.

I believe Paul Krugman is wrong and time will prove it. In the interim, I continue to admire him and agree with most things he says. I simply ignore his pontificating on "climate change". We both agree 100% that climate is changing and has always been changing. Where we disagree is over "anthropocentric global warming". I will admit that CO2 and other green house gases are increasing temperatures but I think he has the basic science corrupted by a reliance on computer modeling. I think the models are misleading. I think the science is incomplete:
I'm not a climatologist. I may be completely wrong. But I do read and I don't see the "consensus" that Al Gore, the IPCC, and Paul Krugman claim has "settled the science". I do see ambiguous data. I do see ideas struggling for a hearing. And I'm aware of how the funding agencies are creating a "false consensus" by putting money out there for "global warming" research. For years I've watched senior scientists who are beyond the tyranny of the funding agencies struggle with theories outside the "mainstream" of global warming. They struggle for a hearing. Since science isn't a beauty contest, I believe that eventually these voices will be heard and the simple "greenhouse gas" story will end up extensively revised by a much more sophisticated understanding of climatology.

Oh... and I heartily agree with Krugman's complaint about the anti-intellectualism and anti-science of the Republican party:
Now, we don’t know who will win next year’s presidential election. But the odds are that one of these years the world’s greatest nation will find itself ruled by a party that is aggressively anti-science, indeed anti-knowledge. And, in a time of severe challenges — environmental, economic, and more — that’s a terrifying prospect.

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