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Missing the Main Arguments
December 2, 2009, 10:00 am
Are skeptic’s really bad at making their case. Or are warming alarmists purposely avoiding the skeptic’s best arguments? That’s the question I am left with after reading this Scientific American article supposedly shooting down the skeptic’s best 7 arguments. Let’s walk very briefly through all seven. If you don’t want to go through these individually, I will preview the ending or you can skip to it: None of these seven include any of the most powerful or central arguments of skeptics. At the end of this article I offer seven competing skeptics claims that never seem to get addressed.
Claim 1: Anthropogenic CO2 can’t be changing climate, because CO2 is only a trace gas in the atmosphere and the amount produced by humans is dwarfed by the amount from volcanoes and other natural sources. Water vapor is by far the most important greenhouse gas, so changes in CO2 are irrelevant.
I have never really relied on this argument, so I am not going to bother with this one.
Claim 2: The alleged “hockey stick” graph of temperatures over the past 1,600 years has been disproved. It doesn’t even acknowledge the existence of a “medieval warm period” around 1000 A.D. that was hotter than today is. Therefore, global warming is a myth.
Without digging into the detail of proxies and statistical methods, it is nearly impossible to discuss the hockey stick in 3 paragraphs. But in the end it doesn’t matter because the author and I agree that it doesn’t matter. The author writes:
But hypothetically, even if the hockey stick was busted… what of it? The case for anthropogenic global warming originally came from studies of climate mechanics, not from reconstructions of past temperatures seeking a cause. Warnings about current warming trends came out years before Mann’s hockey stick graph. Even if the world were incontrovertibly warmer 1,000 years ago, it would not change the fact that the recent rapid rise in CO2 explains the current episode of warming more credibly than any natural factor does—and that no natural factor seems poised to offset further warming in the years ahead.
Leaving off the very end, where he goes sailing into the aether by saying incontrovertibly that the rise in CO2 explains our current episode of warming, he says that the hockey stick isn’t really evidence at all, no matter what it says. I agree. But skeptics weren’t the ones who brought it up as relevant evidence, the alarmists did. If they are walking away from it, fine. [By the way, this is an absolutely core technique of climate science - defend a flawed analysis like a mother bear, claim it is the smoking gun that proves everything, and then when forced to finally accept that it is flawed say that it doesn't matter.]
Claim 3: Global warming stopped a decade ago; the earth has been cooling since then.
His answer here is really an amazing bit of cognitive dissonance. He writes:
Anyone with even a glancing familiarity with statistics should be able to spot the weaknesses of that argument. Given the extended duration of the warming trend, the expected (and observed) variations in the rate of increase and the range of uncertainties in the temperature measurements and forecasts, a decade’s worth of mild interruption is too small a deviation to prove a break in the pattern, climatologists say….
If a lull in global warming continues for another decade, would that vindicate the contrarians’ case? Not necessarily, because climate is complex.
So even a 20 year lack of warming does not disprove that CO2 is causing 0.2C - 0.25C per decade of warming or more, because natural variations could mask this or offset it somehow (offsetting therefore as much as 0.5C by natural variation in the cooling direction over two decades).
Some might ask, can’t the warming be hiding or taking some time off? First, if the theory is right, it can’t be taking time off. It has to warm, year in and year out. It can hide in the deep oceans, but new technologies like the ARGO floats since 2002 have shown no increase in ocean heat content in the 6-7 years. This is why scientists are stuck positing there is some natural phenomenon offsetting the heating with cooling.
But here is the problem, not that any warming scientists are honest enough to raise it. Their entire argument that recent warming has been driven by CO2 (as the author confidently asserted above) is that scientists are unable to explain the warming since 1950 any other way (ie it can’t be explained by natural factors). Leave aside that this assertion is based solely on runs of their flawed models - we will get to that later. Look at the temperature curve for the past decades:
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