Monday, October 15, 2007

Things we don't know about climate change.

(Editor's Note: Garfield's post below is part of Sauntering's participation in Blog Action Day, where 15,000 blogs have agreed to address climate change on October 15, 2007.)

With the award of the Nobel Prize to Al Gore and the IPCC, global climate change has officially hit the big time. It's been trendy for a long time, but awarding the Peace Prize signifies an important recognition on the part of the international community: Global climate change isn't just an effect on the planet, its an effect on how human beings interact with one another.

The reason that global climate change will have such an impact on human interactions isn't because its going to get warmer. Warmer conditions would certainly mean trouble for some, the Maldives most notably, but probably a boon for others as warmer climates mean longer growing seasons and a lower dependence on heating oils. Some win, some lose. Nothing new about that.

What's makes climate change a problem is that so many of the consequences are just so uncertain, and human beings have never dealt well with uncertainties. Here are the facts as we know them.

1) We are dumping more carbon dioxide into the air than the earth has seen since the Bartonian, when sea levels were 100 feet taller and the planet was filled with crazy looking mammals (the later is probably unrelated).

2) The mean global temperature is increasing. We moved up 0.6 degrees Celsius in the last century, and, on average, its just going to keep getting hotter.

3) The world is a terribly complicated place, and we have just about no idea what these changes will mean for our planet. But whatever these changes are, we'd better get used to them, because even if we were all to give up driving right now, there's a general consensus that it will take decades for our planet to process the current glut of gasses in the air.

This uncertainty, I think, is the real problem we're facing. If we knew it was going to get warmer by .06 degrees every decade from here on out, we could plan. As the oceans rise, people would move away from the coast. Farms would move ever northward (or southward if you live down there), and there would be massive-scale efforts to secure the residents of every major city an air conditioner to ward off the rash of heat-related deaths we've seen the past few summers. Or at least this is how it would go in rich countries. Poor countries would be sort of screwed, but I digress. That's someone else’s problem and we have a solution - fences to keep out the flood of migrants...and you'd better believe there would be a flood of migrants as crops to the south begin to fail.

The problem is that we don't know that this is going to happen, at least not everywhere. One of the most surprising findings from both models and actual observations is that some areas may actually get cooler. The gulf stream, that magical river of water that keeps merry old England from feeling the wrath of old man winter like Siberia (which lies on the same latitude) has a real chance of going away if the Artic ice melts, which would pretty much put an end holidays at the beach for most of Western Europe. In the Antarctic, paradoxically, there appear to be areas that are getting cooler, the result, ironically, of the gigantic lack of an important greenhouse gas called "Ozone" right above Antarctica.

The uncertainties seep even into things we feel pretty sure of. One thing that seems certain is that levels of C02 are rising. But it isn't happening as fast as we might expect. The reason is that oceans and plants turn out to be remarkably good at sequestering carbon, at least for now. But they aren't doing it for free. Oceans are able to absorb carbon dioxide through a reaction involving the Carbonate buffer, but at the cost of making the oceans more acidic. This, in turn, is known to affect the ability of organisms to use calcium for building shells and skeletons, leaving us with a lot of sad barnacles, sea urchins, corals, foraminiferans, and coccolithophorids. Never heard of these last two? That's too bad, for you see it is they are producing a fair amount of the oxygen you breath every day. Kind of complex, isn't it? And this is for a system we know a lot about. What don't we know? Pretty much all the rest.

Sadly, we aren't likely to get a better handle on these changes before its too late. Outside of military efforts, less is being spent on scientific research in this country than last year....or the year before...or the year before..... Changes are coming. We'd better start getting used to living with uncertainty.

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