It is just amazing to me that the press has granted statements like the one below the imprimatur of being scientific while labeling folks like me "anti-science" for calling them out:
Previously it was assumed that gradual increases in carbon dioxide (CO2) and other heat-trapping gases in the atmosphere would produce gradual increases in global temperatures. But now scientists predict that an increase of as little as 2˚C above pre-industrial levels could trigger environmental effects that would make further warming—as much as 8˚C—inevitable.
Worse still, a 2˚C increase is highly likely if greenhouse gas concentrations reach 450 parts per million (ppm). They presently stand at 430ppm and are increasing by 2-2.5 ppm per year.
Gee, where do I start? Well, first, the author can’t even get the simplest facts correct. World CO2 concentrations hover in the 380’s (the amount varies seasonally) and is not anywhere near 430. Second, I have demonstrated any number of times that our history over the past 120 years would lead us to expect at most a 1 degree rise over pre-industrial levels at 560, and thus a 2 degree rise by 450 is not "highly likely." Third, just look at the author’s numbers at face value. Catastrophists believe temperatures have risen (reason disputed) about 0.6-0.7 degrees in the last century or so. If we are really at 430 ppm, then that means the first 150ppm rise (preindustrial CO2 was bout 280ppm) caused at most 0.6C, but the next 20 ppm to 450 would cause 1.4C, this despite the fact that CO2 concentations have a diminishing return relationship to temperature. Yeah, I understand time delays and masking, but really — whoever wrote these paragraphs can’t possibly have understood what he was writing.
But I have not even gotten to the real whopper — that somehow, once we hit 2 degrees of warming, the whole climate system will run away and temperatures will "inveitably" rise another 8C. Any person who tells you this, including Al Gore and his "tipping points," is either an idiot or a liar. Long-term stable systems do not demonstrate this kind of radically positive feedback-driven runaway behavior (much longer post on climate and positive feedbacks here). Such behavior is so rare in physical systems anyway, much less ones that are demonstrably long-term stable, that a scientist who assumes it without evidence has to have another agenda, because it is not a defensible assumption (and scientists have no good evidence as to the magnitude, or even the sign, of feedbacks in the climate system).
By the way, note the source and remember my and others’ warmings. A hard core of global warming catastrophists are socialists who support global warming abatement not because they understand or agree with the science, but because they like the cover the issue gives them to pursue their historic goals.
HT: Tom Nelson