Climatic complexity escapes Harvard scientists

[This isn't the second installment in my three-part series on environmental politics. I've got that column almost finished and just need to get some photos scanned -- but I simply had to write a follow-up on global warming, after I read a recent Harvard Magazine article that typifies the simplistic hysteria surrounding the issue... ed.]

FLAGSTAFF, Arizona, December 28, 2002 -- As I argued last time (in "Global warming -- real climate change, or just hot air?", 5/19/02), what's "obvious" isn't always true, in environmental politics.

A big part of the problem, with climate change and global temperature, is that the Earth takes a long time to warm up and cool down, and that it does so through natural circumstances. This is the result of a complex set of phenomena having to do with astronomy, atmospheric chemistry, and -- possibly -- human activity.


If carbon dioxide were the only factor affecting climate, we'd never have had Ice Ages.


Unfortunately, it's easy to assume that human activity is the most important factor. And that's exactly what a recent Harvard Magazine article does, simplifying the issue to just one item: carbon dioxide (CO2).

The article's author, Jonathan Shaw (the magazine's managing editor), lets us know where he stands right from the first page. Quoting a professor of biological oceanography (who can hardly be expected to be an expert on climate, let alone astronomy or atmospheric science), he states that the professor "shares with virtually all his colleagues who study climate change the firm conviction that our world is warming rapidly."

The enemy -- you'll be surprised to hear -- is us. "The largest contributor to recent global warming, scientists believe, is carbon dioxide." This is stated as a neat, tidy, well-established fact -- beyond dispute. CO2 is the only climatic factor discussed in the article -- as if it were the only thing that influenced climate.

It ain't that simple

Would that it were so -- because if it were, that would make the problem easy to fix. Just stop adding CO2 to the atmosphere by burning fossil fuels, and we're all set.

However, if CO2 were the only factor affecting climate, the Earth would never have experienced the vast changes it has undergone in the past. Cycles of glaciation and deglaciation do occur, and on a regular basis -- this, unlike "global warming," has an established basis in scientific fact. If you've ever taken a vacation on Cape Cod, Martha's Vineyard, or Nantucket, you might be surprised to find out that those geographic features are only about 12,000 years old -- they were left behind by the retreat of the last continental glaciers. Twelve thousand years ago, Massachusetts was underneath a mile of ice.


It would be nice if we could just ratify the Kyoto Accord and keep the climate right where it is today; but that's not how the Earth works.


Now, that's evidence of significant climate change. Perfectly natural, no artificial ingredients, not caused by human activity. (What did cause it? Probably, astronomy -- there are a set of factors called the Milankovich Cycles, having to do with the Earth's orbit and the tilt of its axis, which affect the way the Earth receives heat from the sun. The Milankovich Cycles cause the Earth to cool down and heat up slowly, over long periods of time, causing glaciers to march across continents, then retreat toward the poles.)

Does Shaw's article mention astronomy? Nope -- he's convinced that climate change, if it is in fact occurring at the present time, is all CO2, all the time.

As I mentioned a number of columns back (in "All the news that fits, we print"), a lot of editors tend to assume their conclusions -- then, they assign writers to come up with evidence to back up the conclusions they've assumed. They write the headline before they've researched the story. Shaw's article is a classic example of this. What's worse, the aforementioned biologist he quotes is a member of the Intergovernmental Panel on Climate Change (IPCC), which does look at factors besides CO2. For example, the IPCC report does examine "radiative forcing" of climate, which -- as mentioned last time -- John Daly, a Tasmanian climate researcher, feels is responsible for the slight warming the Earth has experienced over the past 150-200 years. (Daly says variations in the sun's output were also responsible for the Medieval Warm Period of 1000-1300AD and the Little Ice Age of 1600-1800AD or thereabouts.) If you look at the IPCC's own charts on the subject, you'll see that sunspot activity correlates nicely with a small warming trend since 1800 or so.

Missed a birdie putt? Global warming!

Nonetheless, Shaw's got his story -- CO2 -- and he's sticking to it. From there, he extrapolates to blame all kinds of things on global warming. The horrible forest fires we had last summer here in Arizona and elsewhere in the Southwest? A result of global warming, he says. (Wrong -- they were the result of bad forest management; too much fire suppression over the last several decades, combined with not enough logging. This led to forest densities of as much as 500 trees per acre in the Coconino National Forest. Natural forest density, when Mother Nature is left to her own devices, is more like 20-30 trees per acre. Dense forests tend to be less healthy, and when they catch fire, they go up like a box of matches, as we saw last summer.)

Ice-free water at or near the North Pole? Global warming. (Wrong again -- open water has long been observed at or near the North Pole from time to time, as was documented almost 200 years ago.)

The type of "the sky is falling" hysteria that continues to appear in the popular press does nothing to clarify what is or is not happening with respect to global climate. It would be comforting if we could simply ratify the Kyoto Accord, cut our carbon dioxide emissions, and keep the climate right where it is today. But that's not how the Earth works. Climate does change significantly over time, through natural forces. A few thousand years from now, most of North America will again be covered with ice -- there's not much we can do about that. And -- contrary to popular belief -- human-induced global warming is far from scientific fact. We may well be influencing the Earth's climate, but the evidence isn't conclusive -- unless, like Shaw and the scientists he quotes, you've assumed your conclusion. And apparently, even Harvard professors aren't immune from that.

Copyright © 2002 Kafalas.com, LLC


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