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Dave,

Thanks for the comments and the reference to the global "theory du jour," which had nowhere near the level of support (or the detailed climate modeling now available) as the current consensus. It is one of the classic, discredited arguments of the political denialists. The scientific skeptics have long since stopped citing it.

In fact, we now know that the 1970s cooling was an effect of increased particulates in the atmosphere due to burning of fossil fuels. (See "The Weather Makers" by Tim Flannery for an interesting discussion of this.) Cleaning up the powerplants removed the masking effect of the particulates and allowed greenhouse gases to have their effect without abatement.

I'd have to dig out my New Scientist article and then trace that to Geissler's journal article to be sure, but I was left with the distinct impression that the changes in albedo were primarily from the main body of the planet and not the poles. Such changes could (and do) go either way, depending on the dust distribution. The article did not mention dust on the poles or increased winds, just a redistribution of dust that happened to produce a darker Mars.

Anyway, the place to settle the argument is in the original Geissler article. Perhaps someone can chime in with the relevant paragraphs or the abstract.

Fred Bortz
Science and technology books for young readers (www.fredbortz.com)
and Science book reviews (www.scienceshelf.com)