Monday, August 13, 2007

Climate Change

My friend Doc has finally pushed me into commenting on this subject - by citing, of all people, the ultimately superficial and glib Mark Steyn on a subject of actual scientific significance - and I comment very reluctantly.

Reluctantly, because I think much of the evidence is of middling quality - the science by its nature has to do most of its work through computer modelling, generally on the basis of imperfect data. Of course this is what much of the science of economics must do as well; part of my youth was spent on economic modelling, so the limitations of such an approach are no surprise to me. But it is ridiculous to pretend this is not a reasonable approach to try to arrive at some truths; certainly it leaves many paths open to falsification, and this is vital.

My priors are clearly very different from that of many others. My guess is we as a species are quite capable of significant impacts on the environment we live in. My everyday experience, however, does nothing to tell me whether I am in some place being significantly affected by climate change. I recall pretty hot brutal summers as a child growing up around Ottawa; I now live in Toronto, with less experience of what it was like. Winters vary. One or two or ten years or tens of years is not the issue here.

I think the issue is over-emotionalized right now, on both sides. If those concerned about acting are right and we act too late, that could have some consequences; I am not sure what, and do not believe most of those promising awful outcomes, especially for Canadians (evidence could sway me)! (The reason I occasionally wonder if Canada is habitable is NOT that it is too warm.) Those who pooh-pooh the concerns seem to me awfully oblivious to what MIGHT be awful consequences.

The quality of the debate is pretty low in a lot of places. Now I tend to lean to markets as good tools for fixing problems, and the parts of the blogosphere I link to regularly in that same domain were a pretty grim disappointment yesterday. Doc, for example, cited Steyn saying:

Something rather odd happened the other day. If you go to NASA's Web site and look at the "U.S. surface air temperature" rankings for the lower 48 states, you might notice that something has changed.

Then again, you might not. They're not issuing any press releases about it. But they have quietly revised their All-Time Hit Parade for U.S. temperatures. The "hottest year on record" is no longer 1998, but 1934. Another alleged swelterer, the year 2001, has now dropped out of the Top 10 altogether, and most of the rest of the 21st century – 2000, 2002, 2003, 2004 – plummeted even lower down the Hot 100. In fact, every supposedly hot year from the Nineties and this decade has had its temperature rating reduced. Four of America's Top 10 hottest years turn out to be from the 1930s, that notorious decade when we all drove around in huge SUVs with the air-conditioning on full-blast.

What triggered the change Steyn refers to was an observation of some anomalies by Steve McIntyre, a global warming skeptic. NASA responded with a recognition that they had erred in calibrating some time series, and corrected them.

Many bloggers I read erupted in some sort of explosion of delight, as if this were actually some sort of actual change. Tim Lambert makes it very clear how insignificant this is except for sloganeers.

Because of the corrections to the GISS data 1998 and 1934 went from being in a virtual tie, to being in a virtual tie.. This, of course, has not stopped global warming denialists from endlessly hyping it as a big change.

Depending on the stability of the various models used, this may or may not lead to significant changes in parameters and the like (UPDATE: It turns out the GISS data have nothing to do with the modelling done to predict the future, at least the way I pictured it - the models are not statistical. ) ; I hope climatologists are pushing on these items, and can update their data as need be. But note, this was only about US data, not world data (a confusion that showed up again among bloggers trying to deny the concern about warming).

Right now I have a policy that when my market-friendly bloggers explode in excitement over something they consider evidence that we need not concern ourselves about anthropogenic climate change, I head to the Deltoid and to Real Climate for some perspective, a dose of sanity. (Actually check this for an even more brutal dismissal of the triumphalism.)

Doc passed on a bit of apparently careless reading from Melanie Phillips (I see no contradiction in the paragraph he cites Phillips as citing - it is certainly possible to have more extreme wet events and an average that is less wet) recently as well in the same vein. On the other hand, the quotations from Tom Segalstad were interesting and none of my usual backup sources have anything to say about his casual dismissal of all of climate science. My guess is they soon will. She also cites Dr. Stott as basically showing he is not sure. Sounds just like an economist.

We shall see. My biggest concern is that I have NO idea what we can do to correct our course. Trying to make everyone poor again, as it seems many of the greenest among us want, just seems a really bad idea to me. Moreover, much of the discourse is fatuous - I could not get more than 10 minutes into Gore's movie before wanting to find a romantic comedy on another channel - it was a bit like 'The Corporation' in terms of its indifference to facts. This is sad - it sets up easy targets. I think the whole thing matters. Wish I had an answer. But I sure have NO easy glib dismissal, and no wish to hear about what Mark Steyn has to say on any issue that actually matters. (I *do* enjoy laughing with him but he is less funny than Michael Moore with roughly an equal commitment to facts.)

In the end I thought that yesterday underlined the truth of this comment

Now, it ought to be obvious that the basis of climate change is rather more complicated than whether 1998 was the warmest year in over a century, or if it was warmer or cooler than 1934. And yet, by having made such a big deal out of 1998 in the first place, or by allowing the media to focus so tightly on that factoid, some folks who perhaps ought to have known better tied the perceived validity of their argument about this critical issue to an inherently weak assertion. As a result, the science of climate change looks a tiny bit shakier today, when nothing of significance has actually changed. There's a lesson here for anyone trying to explain such a complex technical subject to a general population, using mass media in which news coverage has acquired many of the elements of entertainment programming. You can't bore your audience or talk over their heads, but you also can't reduce complex arguments to such thin reeds that they snap at the tiniest shift.


At 10:42 AM, Blogger Ramesh said...

well said. you definitely share many of my sentiments on the matter but I think you're much too pessimistic about the possibility for positive change to avert the worst possible outcomes of climate change. Remember, it's the low probability outliers that should really concern us (i.e. the 90th, 95th and 99th percentile predictions for increase in global average temperature...those are the really scary numbers...Waterworld anyone?)

We need change that doesn't involve devolving to some kind of pre-industrial agrarian paradise like many environmentalists seem to wish. The costs for doing so are actually quire manageable. Consider oil prices. In the last 10 years, average oil prices have increased from about $20/barrel to $70/barrel. If you assume approximately 80 million barrels/day consumption, the $50 per barrel price increase represents an increase in annual oil cost to the world of about $1.5 trillion dollars (about 2% of world GDP). That's a pretty big increase yet the world economy withstood that cost while knocking off some impressive growth, particularly in India and China (8 and 10% annual growth at the same time as a tripling of oil prices is downright amazing!).

Measures to significantly reduce CO2 emissions would almost certainly significantly reduce oil consumption (or at the very least, slow its increase). The cost of these measures will to a large degree be recouped through lower oil prices as demand drops in response (one obvious measure is widespread adoption of plug-in hybrids with an associated increase in nuclear power and renewable electricity generation sources).

At the end of the day, a few hundred billion dollars a year in net costs should have a minimal impact on global growth while significantly reducing CO2 emissions. This will dramatically reduce the income of oil producers (countries and companies) and this is ultimately the source of resistance to such policies.


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