Monday, March 3, 2008

GW: keeping things in perspective

Some thoughts on a recent NYT article on this year's cooling trend:
March 2, 2008
Skeptics on Human Climate Impact Seize on Cold Spell
By ANDREW C. REVKIN

The world has seen some extraordinary winter conditions in both hemispheres over the past year: snow in Johannesburg last June and in Baghdad in January, Arctic sea ice returning with a vengeance after a record retreat last summer, paralyzing blizzards in China, and a sharp drop in the globe’s average temperature.

It is no wonder that some scientists, opinion writers, political operatives and other people who challenge warnings about dangerous human-caused global warming have jumped on this as a teachable moment.

...

So what is happening?

According to a host of climate experts, including some who question the extent and risks of global warming, it is mostly good old-fashioned weather, along with a cold kick from the tropical Pacific Ocean, which is in its La Niña phase for a few more months, a year after it was in the opposite warm El Niño pattern.
It's refreshing to read a story about global warming that doesn't claim there is a "consensus" on the matter or that "the debate is over." Of course this really isn't a story about global warming; it's a report of evidence that runs counter to the global warming theory.

So the "consensus" is now a "host." And that host actually includes "some who question the extent and risks of global warming."

It's nice to see that those "political operatives and other people who challenge warnings about dangerous human-caused global warming" have something to contribute for a change, instead of being dismissed as "deniers" of the faith. How reasonable all these crazies are now that they are making a point that the "consensus" embraces.

Notice, also, the sudden restraint being shown by the global warming bunch--how they caution us that a period of record cooling doesn't indicate a longterm trend, that weather fluctuations are normal, and that this is a "teachable moment."

Yet I recall many instances of severe hurricanes or other weather phenomenon being offered up as "proof" of man-made global warming. I don't remember those being described as "teachable moments" when the "deniers" tried to make the same points.
If anything else is afoot — like some cooling related to sunspot cycles or slow shifts in ocean and atmospheric patterns that can influence temperatures — an array of scientists who have staked out differing positions on the overall threat from global warming agree that there is no way to pinpoint whether such a new force is at work.
Now isn't that interesting. The "deniers" have been pointing out for years that the computer models being used to forecast global warming gloom-n-doom don't take into consideration things like solar activity -- i.e. the Earth (and the other planets) get hotter when the sun becomes more active. Now that things are cooling off, the "consensus" is suddenly discovering the importance of such phenomena; solar activity and ocean and air patterns are considered "new forces at work." I'd be curious to know how these factors contribute to global cooling and not global warming.
More clucking about the cold is likely over the next several days. The Heartland Institute, a public policy research group in Chicago opposed to regulatory approaches to environmental problems, is holding a conference in Times Square on Monday and Tuesday aimed at exploring questions about the cause and dangers of climate change.

The event will convene an array of scientists, economists, statisticians and libertarian commentators holding a dizzying range of views on the changing climate — from those who see a human influence but think it is not dangerous, to others who say global warming is a hoax, the sun’s fault or beneficial. Many attendees say it is the dawn of a new paradigm. But many climate scientists and environmental campaigners say it is the skeptics’ last stand.

Michael E. Schlesinger, an atmospheric scientist at the University of Illinois, Urbana-Champaign, said that any focus on the last few months or years as evidence undermining the established theory that accumulating greenhouse gases are making the world warmer was, at best, a waste of time and, at worst, a harmful distraction.
Ah, global warming skeptics are "clucking at the cold" and hold "a dizzying range of views." Now we're back on message.

And note the non sequitur. Schlesinger's comment is placed so as to suggest that the conference itself is a waste of time. But Schlesinger is commenting only on the issue of whether a small slice of data can tell us anything about a longterm trend. There's nothing in this story (or anywhere else I'm aware of) that suggests that anyone at the conference will be making that case; to the contrary, it sounds like the convention will be addressing global warming in its entirety.
Interviews and e-mail exchanges with half a dozen polar climate and ice experts last week produced a rough consensus: Even with the extensive refreezing of Arctic waters in the deep chill of the sunless boreal winter, the fresh-formed ice remains far thinner than the yards-thick, years-old ice that dominated the region until the 1990s.
A "rough consensus." Have to get that consensus word in there somewhere, I guess. But note, the issue is whether the Arctic ice is thinner now than it was before 1990. This is a point of fact -- either it's thinner or it's not.

If the best we can do is get a "rough consensus" from our polar and ice experts on this single, measurable data point -- and if solar, air, and ocean patterns are considered "new forces" which aren't fully understood -- how can we have any degree of confidence (let alone a consensus) on what's going on with our complex climate system?

Let the debate continue.

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