Thursday, March 26, 2009

A New Era for Science

Two science-related news stories have stuck with me this week, though admittedly the second one is rather new.


Antarctic Ice Melt

Morning Edition, March 19, 2009 · A huge chunk of Antarctic ice can't withstand nonstop global warming, according to a new study published in the latest Nature magazine. And if it melts, the ice will raise the global sea level by 15 or 20 feet — or more.
(NPR)
OK so far? Then the story quickly turns puzzling:
The ice in question is called the West Antarctic ice sheet. In some ways, it's the planet's Achilles' heel. It holds a vast amount of water, locked up as ice, and it's sitting below sea level, so it's inherently unstable.
So ... ice below sea level is supposed to raise the level of the oceans as it melts?

First, I doubt that this notion came directly from any scientist interviewed by NPR. Second, if a scientist did say it then the statement should require a pretty good explanation. After all, about the only way that a block of ice melting below sea level can significantly affect the level of the ocean is if the hollow in which the ice is located goes dry. As in no ice and no water either.

Remember, water is that odd substance that is more compact in its liquid state. That's why ice floats, and it's also why a glass of ice water stays at about the same level when the ice melts.

The Reuters version of the story clarifies things a bit better:
The floating ice shelf won't elevate sea levels if melts because it is already displacing water. The real threat comes when the ice sheet behind, which is below sea level, is exposed to the ocean.
Though the "real threat" remains a bit mysterious without further reading ...
The modeling showed that when the West Antarctic ice sheet collapsed, and the much larger East Antarctic ice sheet continued to melt at the edges, global sea level rose seven meters above present day levels, said Pennsylvania University's David Pollard, who led the study.
Did higher sea levels cause the melt or did the melting cause higher sea levels? Or both, with plenty of scope for adjusting the percentage?


The Science of Obama

President Obama generates an aura of awe surrounding his intellect, including his understanding of science, though we don't seem any solid indication that he grasps science any better than the average person. He did end up a lawyer rather than a scientist, after all.

Power Line pointed out a rather strange application of science by Obama with respect to Red River flooding, via The Star-Tribune:

In a White House interview with a handful of reporters, including Janell Cole of the Forum of Fargo, the president said the current flooding cannot necessarily be blamed on global warming, but he said it should be a signal to act.

"If you look at the flooding that's going on right now in North Dakota and you say to yourself, 'If you see an increase of 2 degrees, what does that do, in terms of the situation there?' " the president told the reporters. "That indicates the degree to which we have to take this seriously."

If the two degree increase happened overnight and in the spring, then the flooding would be worse, assuming the same amount of ice melt going into the river. But a two degree increase over time probably lessens the amount of ice to begin with, so there's less melt to go into the river in the first place.

Perhaps the president had in mind a "The Day After Tomorrow" scenario where North Dakota is struck by sudden torrential rains as a result of global warming. Or something.

I wouldn't be at all surprised if this one serves as a strong candidate for Ed Morrissey's Obamateurism of the Day over at Hot Air.


Mar 27, 09: Provided a forgotten "is" for the first graph

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