Thursday, June 3, 2010

The climate blogging's been a little thin on the ground in the past couple weeks. This was a result of a combination of IRL events -- I received my doctorate on Tuesday! -- and slack-jawed amazement at the events of recent days and the bottomless chutzpa of the denier noise machine.

We begin in Greenland, where Willis Eschenbach starts by mangling the English language with that same trademark mixture of arrogance and stone ignorance that characterizes his "science" pronouncements:

This topic is a particular peeve of mine, so I hope I will be forgiven if I wax wroth.

This is silly, sloppy usage of pointlessly archaic language, stylistically wretched, but not erroneous. However, having started down the path of Ye Olde English douchebaggery, the words quickly get away from Willis:

That’s what angrifies my blood mightily

Seriously. That's what he said.

The "science" content of the post is equally disturbing. Willis is "angrified" by an article in the popular press which presenting the findings of the GRACE satellites, and calls loss of hundreds of cubic kilometers of ice each year "some of the most powerful evidence of global warming." Not so, according to Mr. Eschenbach:

And when we do so, we find that the annual loss is around 200 km^3 lost annually out of some 3,000,000 km^3 total. This means that Greenland is losing about 0.007% of its total mass every year … seven thousandths of one percent lost annually, be still, my beating heart …

And if that terrifying rate of loss continues unabated, of course, it will all be gone in a mere 15,000 years.

The loss of 200 km^3 of ice per year is not “some of the most powerful evidence of global warming”, that’s hyperbole. It is a trivial change in a huge block of ice.

To understand the glaring problems with that little slice of Polyannism, let's look at the actual peer-reviewed research. Money quote:

Using a simple elastic model, we estimate that western Greenland’s ice loss is accelerating at an average rate of 8.7±3.5 Gt yr−2, whereas the rate for southeastern Greenland—based on limited data—falls at 12.5±5.5 Gt yr−2.

The mass loss is accelerating. In fact, at the current rate of acceleration, the rate of loss -- the "trivial" 200 cubic kilometers washed out to sea -- will double in the nine years. But the rate of acceleration itself may change -- it may accelerate or decelerate. The one thing we can say with reasonable confidence is that the rate won't stay the same. Which is exactly what Willis assumes when he ignorantly/deceptively complains that "Hey, at this rate, it won't be gone for 15,000 years!"

In fact, if the acceleration of the melting -- the rate of rate change -- were to remain constant, two-thirds of the ice would be gone by the end of the century, with a 4m sea rise.

But there's another level of fallacious reasoning here, which is that Willis is claiming to refute not the notion that the Greenland warming is directly dangerous (it clearly is) but rather that it is "powerful evidence of global warming." Which it obviously is; Greenland has gone from no net loss of glacier ice to the loss of hundreds of cubic kilometers per year. That is powerful evidence of global warming, even if the volume is (for the moment, touch wood!) a very small percentage of the total ice mass per year.

That would be the difference between how scientists think, and how Willis thinks: in science, a change is not "trivial" because it fails to meet some arbitrary Michael Bay-esque standard of instant cataclysm. But details like that bore Willis. At least, they bore him when the changes provide further evidence of anthropogenic global warming, the white whale to his self-crippled Ahab.

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