Saturday, April 1, 2006

Global Warming

Global warming, in the sense that most people I know understand it, is the notion that the Earth is getting catastrophically hotter, and it’s all mankind’s fault. The thesis is that our activities create greenhouse gases, which in turn trap solar radiation on the Earth’s surface and raise the temperature.

If you’re interested in understanding the truth of the matter, rather than simply being comfortable as the lapdog of the politically-correct environmentalist whackos, there are two important questions here:

1. Is the temperature of the Earth rising?

2. If so, are mankind’s activities causing or contributing to that rise?

Despite all the blather you hear in the lamestream media (and worse, from pandering politicians), neither of these questions has been answered. There are competing theories on both sides of the questions, and a dearth of evidence to prove either one.

On the first question, the challenges are these: (a) mankind first learned how to measure temperatures accurately less than two hundred years ago, and we need thousands of years of data to know if things have changed in the past 150 years, and (b) the change we’re trying to observe is on the order of a few degrees, while the normal variations from day-to-day and year-to-year are tens of degrees. On the issue of temperatures in the past, clever scientists are coming up with lots of ways to infer and estimate past temperatures, and the results of those are, as you might expect, conflicting, uncertain, and not particularly accurate. Some of these estimates of past temperatures rely on modeling, which (despite my being a computer professional) I am always skeptical of. It’s not the fact that the models are created by computer that makes me skeptical, it’s the fact that models (no matter how they’re made) are based on a bunch of assumptions about the thing being modeled — and usually, to make the model easier to compute, the model is also based on estimates. Modern computer-based models produce beautiful graphics and “movies” that make terrific presentations — but I think they entrance their producers into belief, much like “spreadsheet syndrome” entrances business users into believing the financial model they’ve computed (to 14 decimal places!) on their Excel spreadsheet. Nevertheless, the scientific community, from my reading, seems to have arrived at a consensus that there is a small increase in global temperatures over the past couple hundred years. I’d say there’s a good chance the consensus is correct.

But that leads to the next question, and here’s where things get really uncertain. Why? Why is the earth getting warmer?

The easy answer, and one that’s very attractive to those of a certain political mindset, is that mankind’s activities did it. //iWe// did it, it’s all our fault. I’ve long been intuitively skeptical of this notion. The oft-repeated, hoary old saw of the anti-global-warming crowd resonates with my intuition: we can’t even make a little thing happen (say, rain when we need it) on purpose — so how is it that we’ve caused the whole planet to heat up inadvertently? Now I know that’s not a defensible piece of logical analysis, but it is nonetheless an interesting point. Do we really think that mankind’s puny little activities can compete with mother nature when it comes to climate change?

But lets set my intuition aside, and go look at the evidence. In general, one can observe that proving a cause is more challenging than proving a fact. To illustrate: I can easily prove that the sun is shining; to prove that it shines because of nuclear fusion is much more difficult. The same relative difficulty applies to proving (or even just guessing at) the cause(s) of global warming. First of all, there are many candidates, of various likelihoods, for the causes; greenhouse gases caused by mankind’s activities is but one of them. Others include greenhouse gases produced by volcanoes or biological activity, increased radiation (brightness) of the sun, meteorite strikes, and many more. Greenhouse gases in general feature in several of these propsed causes, but it turns out that it isn’t actually a certainty that greenhouse gases will increase temperatures. We can’t make experiments to actually observe this, so the scientists rely on computer models (alarm bells should be ringing in your head!). These models make all sorts of assumptions about the effects of greenhouse gases. One of these effects — arguably the most controversial one — is how increased temperatures would affect cloud formation (remember we don’t actually know, from observation, any of this — these are assumptions). One school of thought is that increased temperatures will cause increased cloud production, through increased plant life and more water in the air. If that’s the case, the increased clouds will reflect more of the sun’s radiation, which will tend to cool the earth, offsetting the effects of the greenhouse gases. The real point is that we just don’t know the effects for sure.

Another of the possible causes has been in the news recently: increased solar radiation. Two completely separate studies (of different phenomena) offer evidence of increased solar radiation in the past few centuries. One of those studies is earthbound, and provides evidence that the sun’s magnetic activity has increased (and this is correlated with increased radiation). The other study shows that Mars is coming out of an Ice Age of its own, and the only plausible cause for that (on Mars) is increased solar radiation. Interesting stuff, but not proof that increased solar radiation is causing the Earth’s global warming.

This is one of those complicated topics that can’t possibly be covered adequately in a short post (if you call this short!). I’ve provided links to much more reading below, if you’re interested. There’s good reason, I think, for all of us to become informed enough to have an opinion on this topic: various politicians (such as Al “father of the Internet” Gore) want to spend a large fraction of your money on the unproven assumption that mankind’s activities are causing global warming. If they’re wrong, we’d simply be wasting that money; you might as well just burn it on your front lawn. The really sad part, though, is this: even if they’re right, even radicals like Al Gore are proposing very small changes that will not even make a dent in mankind’s production of greenhouse gases. For example (something you won’t learn from the lamestream media): the much-ballyhooed “Kyoto Treaty” (a favorite of the Gore) would only reduce mankind’s production of greenhouse gases by 4% to 6%, even if fully implemented! The main reason for that is the Kyoto treaty completely excludes India and China — two of the largest greenhouse gas producers, and (under the Kyoto treaty) completely without incentive to improve. In fact, their economic incentive would be to not improve. One last little factoid on the Kyoto treaty (again, one you won’t read in the lamestream media): how have the signatories to the treaty been performing? Well, it looks like at best, one country will meet their obligations (Ireland). Every other signatory is far, far from the mark — and most have publicly given up. And to put the icing on that particular cake, the U.S. — without being a signatory — is out-performing every single one of the signatories. All that hand-wringing! All that despair from the Gore! And we’re beating every one of them without their economy-destroying policies.

Take that and smoke it in your pipe, you environmentalist wackos!

More reading here, here, here, here, here, and here.

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