Many concerned climatologists have pointed to the retreat of glaciers over the past several decades as evidence that Earth’s climate is indeed growing warmer. The animated image at left, created by Malin Space Systems, shows a region of the south polar cap photographed on the same date during three consecutive years. The shrinkage is obvious.
What is not obvious is that this is not Earth, but Mars as photographed by the Mars Global Surveyor, which has been observing the Red Planet in exquisite detail since 1999. The ice is frozen carbon dioxide, which is very cold stuff, but it is apparently getting warmer for some reason.
If this region of Mars is indeed warming up, what could be the cause? Increased solar activity? We don’t know, but the concentration in Greenland ice cores of Beryllium 10, created by cosmic rays in lower abundance when solar activity increases, suggests that the sun has indeed been running hotter for the past 60 years. While the observed warming of earth may be due in some degree to the greenhouse gases that we are pumping into the atmosphere, the fact that something similar is happening on another planet should give us pause. We clearly don’t have all the answers.
ADDENDUM, December 10, 2005. Since this was posted, a number of environmental websites have published articles dismissing evidence of Martian global warming as irrelevant. The writers commonly use a rather tautological argument — that we’ve not been able to take data with sufficient resolution for a long enough period to establish that this is anything more than a minor fluctuation in Mars’s climate, and that we have only evidence of recent warming on Mars. Obviously, since we have been able to make these observations only since 1999, we cannot say anything at all about the recentness of the warming. We have only recent data, for heaven’s sake! But climate-change experts are only too happy to cite a mere 50 years of direct measurements to prove that solar flux is invariable — as if it might not take centuries for a planet to respond to a slight variation in solar output.
I really don’t have a huge axe to grind. Do I think that many so-called environmentalists are misanthropic Marxists and pagans? Yep. Do I think that Greenpeace and the Green Party have a tad more than their fair share of hysterical ignoramuses? You bet. Do I think that scientists are not necessarily wise and noble seekers of truth, but are in fact ordinarily self-interested human beings who are perfectly willing to embrace fads in their quest for funding and tenure? Yeah, I’m afraid so. The scientific method has amply demonstrated its efficacy, but as far as the “scientific community” goes, I’ve worked with some of the smartest scientists on the planet, and have found that most of them are, of necessity, so specialized that that they end up knowing a great deal about very little — and many do not hesitate to shovel manure to fill the lacunae.
Nevertheless, I’m rather fond of this planet and I want it to remain beautiful for my kids. To help make that possible, I contribute royalties to the Nature Conservancy, an organization that employs an incredibly radical strategy to preserve wilderness areas: it buys them. The Conservancy seems to do a good job and has, so far, eschewed the Chicken Little approach that has discredited much of the environmental movement.
Environmentalists were happy to promote Venus as an example of greenhouse warming run amok. Why dismiss data from Mars that does not fit a political agenda? If we are to be responsible stewards of our world, should we not welcome any information that may further understanding of these very complex processes?
ADDENDUM; August 14, 2007. In reviewing this I came upon a report from last April that attributes Martian warming to excessive dust in the atmosphere. The mechanism sounds plausible. Of course, if earth’s atmosphere were found to be unusually dusty, it would be instantly attributed to man-made global warming. You can’t lose when you play this game.