It's OK to deny global warming, but ...

Despite what you may have heard from less sophisticated environmentalists, it iss OK to deny humankind is responsible for climate change. Like Gov. Sarah Palin, for example, you may accept that the world is warming at troubling rates, but reject the notion that fossil-fuel emissions are the cause. Fair enough. But to be taken seriously, you then have to offer an alternative hypothesis for the warming.

Your alternative theory, presumably some sort of natural cycle, also has to explain why the observed warming since the advent of the industrial revolution precisely matches what our computer climate models say industrial emissions would produce. Furthermore, it must explain why those industrial emissions aren't warming the Earth, as our understanding of physics and chemistry say it should.

This is why independent researchers like David Dilley of Global Weather Oscillations, who argues that the moon's gravitational pull is responsible by redistributing atmospheric high-pressure zones in a 230-year cycle that is due to reverse in a few years, are not taken seriously by other scientists. Dilley's failure to get his theory published in a peer-reviewed scientific journal helps explain why climatologists won't even both responding to his ideas. But the main problem is he doesn't try to account for all the observational data at our disposal, nor does he and his fellow "skeptics" make a stab at explaining what's happening to all the heat that is being trapped instead of re-radiating into space, thanks to certain, most organic, molecules found in fossil-fuel emissions.

You will find references to Dilley's "Primary Forcing Mechanisms" on climate change denial websites, like Australia's Jennifer Marohasy, but not on sites that respect the scientfic method.

By the way, it is not OK, at least, not from a scientific perspective, to argue that the warming isn't real. Even the much-misrepresented "hockey stick" that shows an historically unprecedented rate of warming since 1750 (the blade) after more than a thousand years of relatively stable temperatures (the handle) has recently been confirmed with independent climate data. (See the graph above, which is taken from a just-published issue of the Proceedings of the National Academy of Sciences.)

James Hrynyshyn's blog posts are provided by LifeWire, a part of The New York Times Company.