Tatterdemalian:

Thanks for the input. Looking at the link you cite, there are several brief quotes pulled from various sources. Several refer specifically to either the Antarctic ice cap (or "ice sheet" -- same thing), or to the Greenland ice sheet. In the case of Antarctica, it appears that the ice cap is, indeed, thousands of meters thick (not just 3 or 4 meters). The one that doesn't refer specifically to the Antarctic or Greenland is ambiguous. Not clear what region is meant.

In the main body of the page it says specifically: "The greatest ever measured thickness of the Antarctic ice is more than 4,770 meters thick!" (i.e., 4.8 kilometers.)

That's probably correct. But they're talking about the South Pole, not the North Pole. Whole different thing. A continental ice cap is not the same as an oceanic ice pack.

As you know, the U.S. Navy routinely operates submarines under the Arctic ice pack (and has done since the 1950s). If the ice pack, on average, extends thousands of meters down into the Arctic Ocean, doesn't that imply that our subs are operating at depths of thousands of meters below sea-level? The Navy has a one-of-a-kind research sub -- USS Dolphin [see: http://www.answerbag.com/q_view/7080] -- which has an operating depth of 3000 feet (915 meters). I have to assume that the boomers don't go much deeper (I think their exact limits are classified, but I've always heard about 2500 feet -- way less than one kilometer).

Here's an article that looks authoritative [http://www.eoearth.org/article/Arctic_Ocean] by Prof P.D.N. Hebert of University of Guelph in Canada. He says that the thickest spots in the Arctic ice are 50 Meters (not 10, as I suggested). But that's still way, way less than 5 kilometers (i.e., 5 thousand meters). Smaller by a factor of one hundred. He also mentions that the floor of the Arctic Ocean is about 3 to 5 kilometers below the ocean surface. If any of the ice is 5 kilometers thick, then it either sticks up hundreds of feet above water level (which it doesn't) or extends deeper than the ocean floor, which it can't.

And Prof Hebert agrees that the area of the Arctic ice pack is in the neighborhood of 9 to13 million square kilometers, depending on the time of year. Not the much, much smaller 1.6 million square kilometers cited in the article.

The BBC interview, according to the Big Hollywood article above, talks specifically about the Arctic, not the Antarctic. It's possible that the writers or the people in the clip were confused or misspoke, mixing up Arctic and Antarctic. It's easy enough to do. That would make the thickness number look more correct (Antarctic ice is indeed several kilometers thick, not just a few meters). But the area of the Antarctic ice cap is about 13.7 million square kilometers (per the CIA Fact Book). Again, way, way bigger than the 1.6 million square meters cited by the article. The article numbers don't seem to correspond to reality in any obvious way.

(And, yes, as another poster said, the Antarctic ice cap is definitely getting bigger, not smaller. A point that is carefully ignored in the media.)

The point is not to get all anal about some measurements. The point is that if you're a global-warming skeptic you can't make mistakes like that in public. We expect Al Gore to repeat whatever the voices in his head say to him be applauded for his wisdom. His opponents can't.

We would jeer (quite correctly) at Global Warmers who scramble their stats, or who couldn't distinguish between the North Pole, South Pole and Greenland. Skeptics, since they are presented in the mass media as ignoramuses, need to be just that much more scrupulous.

Again, I'm not a scientist and I could be wrong. But the numbers cited in the article still look weird to me. I invite correction if somebody's got better info.

- JCL

First: I am not a fan of Greenpeace or the global-warming zealots. I am skeptical (or, as they like to say: a "denier").

But... the figures cited in the article for the Arctic ice pack (technically, since it's floating in the ocean and not "capping" anything, it should be called "sea ice" or "pack ice") are wrong. I don't know whether the writers are accurately quoting strange numbers from the BBC guy in the interview (I haven't watched the clip) or whether they misunderstood or mis-transcribed what they heard, but the numbers in the article appear to be not just wrong, but wildly, completely-outside-the ballpark wrong.

Consult any source you think of as independent and trustworthy: a standard, recent encyclopedia; a college geology textbook. or whatever. You'll see that the extent of the Arctic ice pack varies between about 9 Million Square Kilometers (in summer, when it shrinks) up to about 13 Million Square Kilometers in the winter (when it expands). For very rough ballpark purposes, let's say it averages 10 Million Square Kilometers, to make the arithmetic easy.

The average thickness is between 2 and 4 Meters (NOT kilometers) depending on time of year. (Even in the thickest spots, it's rarely more than 10 Meters, max.) Call it 3 Meters on average over a year.

The numbers cited in the article -- area of 1.6 million square kilometers and maximum thickness of 3 Kilometers -- are off by a factor of five for the first and a factor of one thousand for the second. Something is wrong here.

So, I don't know what to say. I want to support the skeptics, because I think there are good reasons to be very skeptical of the global-warming claims. But you don't get to make up your own facts. I'm not a scientist, so I may be missing something. But as far as I know, the sun is (about) 93 million miles away, the moon is (about) 240 thousand miles away, and the average size of the Arctic ice pack in recent decades is (about) 10 million square kilometers. If somebody else has better information, I would be glad to hear it.

-- JCL