Wednesday, January 23, 2008

Science Lesson Part I

I promised the other day that I'd actually write something substantive about science, so here it is. (I can't resist mentioning it though: I did indeed take my record-breaking third shower of the season a few days ago...)

I had a really interesting conversation yesterday with this professor from Dartmouth who just arrived at the Pole as part of a joint Norwegian-US Traverse, and I think it may spawn another Economist article. It has to do with ice sheets, global warming, rising sea levels, and how you go about figuring all this stuff out.

Let me back up a little bit. Everyone knows about global warming. And everyone knows that one of the really bad things that could happen with global warming is a rise in global sea levels. There's this nice google map that shows what parts of the world will get flooded when sea levels rise. It's pretty cool. You can adjust the amount of sea level rise and then check out your own favorite neighborhood-Bangladesh, Manhattan, Florida, etc.- to see if it's still above water or not. Anyway, rising sea levels come from two things. First off, as temperatures increase, water expands. This is just basic science: hotter things take up more room. In a hot air balloon, turning on the flame heats the air in the balloon. The air expands and the balloon becomes buoyant.

The second cause is the big one. When you melt ice that's sitting on land (such as the three mile thick ice sheet I'm sitting on right now), the water flows into the ocean and causes the sea level to rise. Just to be clear, this only happens for ice sitting on land, not ice that's already floating on water. The usual analogy is an icecube in a full glass of water. When it melts, the glass doesn't overflow. This is because the meltwater takes up the space that the ice was already taking up. Because of this, all the stuff you see on the melting of the Artic and the North Pole doesn't contribute to rising sea levels. That ice was already floating in water. The melting of the Artic is alarming for other reasons which I won't get into right now...

This brings me back to Antarctica. Most of the Earth's fresh water is locked up in the icesheets here, so obviously what they're doing is really important for sea levels. We do know that West Antarctica, the part that juts out towards South America, is warming up and melting really quickly. The problem is that the ice in East Antarctica, the huge part closer to where I am, may actually be getting thicker. That's because, in a warmer climate, it's expected to snow more. That snow falls onto the ice and stays there. If more snow falls than ice melts, the sea level actually goes back down.

So here's the real kicker: we don't actually know if Antarctica is losing ice or gaining ice, overall. There are models and calculations and some satellite data, but there's very little on the ground data from East Antarctica. We just don't know. I even think the recent IPCC report concluded that it was too early to say whether Antarctica is losing ice or not (though I have to check on that).

This is all an interesting little tidbit. One that doesn't usually get reported amidst all the scary stuff you see on the news. I'm guessing the media thinks that people are too stupid to digest complicated information. "Well, if Antarctica isn't melting, that means that global warming isn't real and we don't have to do anything about it." I trust you guys more than that.

So how do we figure out what's really happening in East Antarctica? I'll save that for Science Lesson Part II. But for those of you who just can't wait, I'll give you a preview: You get in some tractors and you spend two-and-a-half months driving across the ice...

Sunday, January 20, 2008

Thwarted!

Well, I had just gone for a long, stinky run and was psyched to take my record-breaking third shower of the season. I walk into the bathroom just as this guy is posting signs saying that all showers are forbidden for the next few days. Apparently they're doing maintenance on the well where they melt the snow to get our water. Damn.

For whatever reason, I feel like I'm only writing about hygiene this year. You all must be getting bored. I think I'll make my next few posts about something interesting and scientific, just to keep y'all entertained :)