Monday, August 28, 2006

The Sporting Mind

This post is an old version, left here for reference, for those who wish to see how it looked when I first published it. The final version is here.

Some people seem to look at the world through the lens of a team sport rivalry. To me, growing up without television or trips to the rink, team sports were something I looked at, not through; and I viewed them as a sometimes alarming curiosity. Now it occurs to me that perhaps others were so deeply involved and immersed in the world of sports that it became their window, their frame of reference when looking at the wider world beyond.

Take, for example, this post by Kate at Small Dead Animals. She asks, "Is Anyone Else Keeping Track?" Ah, the stats. Actually, I have wondered what the world would be like if people paid as much attention to the stats of nature observations as they did to the stats of baseball. But that's an aside. Here's the first part of Kate's post.
Drought, floods, severe winters, warm winters, more frequent storm activity, less frequent storm activity, early frost, early thaw, receding glaciers.

All have, to the best of my recollection as a news consumer, been cited by one climate research expert or another as evidence of "global warming".
Wait a moment. Who is doing the "citing"? Who is calling these events or observations "evidence"? Can you really use your "recollection as a news consumer" to summarise the activities and opinions of "climate research experts"? Kate goes on:
The same experts will also quickly caution that even in the midst of dramatic climate change, one should expect periods of "average" rainfall, temperature, storm activity.
"The same experts"? Try substituting "journalists" for "experts." I don't think you would hear an expert talking about expecting average conditions. Instead, they might talk about conditions being in constant fluctuation, swinging widely above and below an average that is creeping almost imperceptibly. Who can remember whether winters were colder back in one's childhood, or whether they just didn't make boots quite as warm back then? Or whether we had to stand outside more when we were kids, waiting for the school bus? I remember a bitter December cold spell in the late '80's, but of course I don't remember what that winter's average was like. I remember Dad working outside in his shirtsleeves in February some years earlier than that, too. But those are just fluctuations. What the averages were, I couldn't possibly begin to guess. And then, to guess at averages around the globe? Absolutely out of the question. Or to try to compare a grandparent's recollections with my own? Pointless. They say they walked ten miles to school every day, and ten miles home again, and it was uphill both ways.

We remember (and embellish) the extremes, the unusual. We remark on the remarkable. The average is forgettable. In fact, our brains function by tuning out the background and saving perceptive and processing power for anything new and different.

Most of what we see in the news being linked to global warming is not what the experts would call "evidence." In fact, I doubt that most experts would talk about "evidence" at all. They would talk about observations, and whether these observations are in accord with what is expected based on a current hypothesis about climate systems, or whether these observations indicate that a hypothesis should be rejected.

UPDATED: Ouch. I did some reading to refresh my recollections about scientific method and such. I shouldn't have been so dismissive of the term "evidence" when talking about science. I've added the word "popular" to the sentence that follows, but much of this post feels uncomfortable to me now. Comments welcome.

The popular concept of evidence does not fit well in the realm of science. It fits more naturally in the realm of a courtroom, of course, but it also fits well in the realm of team sports. A goal is evidence of a team's prowess. Pile up enough goals in the time allotted, while preventing goals by the other side, and your team is declared the winner.

Science works quite differently. A single conflicting observation can bring down or "falsify" a hypothesis. Of course, there will be checking and double-checking to find out whether there was something false about that one observation, but if it holds, then the hypothesis does not. A new hypothesis might bear considerable resemblance to the old, rejected hypothesis, but it will take into account the new observation. Contrast sports, where it doesn't matter how well executed that goal was; if it wasn't made by the winning team, it doesn't carry the same weight.

Most of the phenomena that Kate listed are discussed by some experts, but not as evidence of global warming. Instead they are predicted as outcomes of global warming. If they fail to appear, or if different outcomes appear, then it is the predictive models that are shown to be lacking. That doesn't mean that evidence has been struck down; it wasn't evidence in the first place.

A couple of the phenomena that Kate listed come close to the kind of observations that climate researchers would consider when questioning whether global temperatures are increasing as expected, or not. Winters would be considered, not in terms of this or that winter being "severe" or "warm," but in terms of average winter temperatures trending colder or warmer. Early thaw has been observed as a long-term trend in western Canada, based on indirect observations such as peak runoff volumes, and flowering dates of poplar trees at Edmonton (which have moved a full month earlier over the course of a century). Observations like these help to refine surface temperature estimates which otherwise are based on incomplete or inadequately controlled instrumental records. UPDATED: It occurs to me that the shift in flowering dates for urban poplars would be subject to the same urban-heat-island problem that affects parts of the instrumental record. This problem is mentioned in a 2002 article (pdf) about the shift in flowering dates (Beaubien and Freeland).

Then we come to Kate's final listed phenomenon, "receding glaciers." Glacier length has been used as a proxy when estimating past temperature regimes. It has the advantage of slow change, which means that it provides a built-in averaging of the temperatures affecting the glacier. However, it is greatly complicated by the influence of changes in precipitation, and may also be influenced by other factors such as dust absorbing solar radiation and heating the glacier surface, tectonic activity, ice within the glacier crossing threshholds of density and fluidity, and so on. Again, averaging is important when interpreting glacier length, to control for some of these other factors by averaging across a large number of glaciers.

But Kate gleefully seizes on a report about western Himalayan glaciers as the final item to complete her list of contradictions in the "evidence of 'global warming'."
With today's addition of expanding glaciers, the list is finally complete. It's therefore, official - climate change proponants have taken ownership of virtually every local and global weather phenomenon worthy of newspaper ink, including "average".

One would think that more people would have noticed.
Actually, the news item is not clear about whether expanding glaciers is an observation, or a prediction - it sounds more like the latter, in which case it certainly can't be criticized as wacky evidence. UPDATED - it's an observation, and related work at explanation and further prediction, as I noticed when I read the university press release (link below) - but I forgot to come back to this paragraph and change it. But perhaps Kate intended to suggest that "climate change proponents" are doing proactive damage control, coming up with a way to explain glacier expansion as an effect of global warming before somebody observes glacier expansion and calls it evidence of global cooling.

"Climate change proponents" - I like that. As if these researchers are hoping for a big, bad change.

Now, let's look closer to the source of this news item. The press release from Newcastle University mentions the title of the forthcoming journal article: "Conflicting signal of climatic change in the Upper Indus Basin." Hardly sounds like these researchers are trumpeting their goal scored in support of a global warming win. Sure, Kate can interpret it as a sly move to protect their cherished theory from conflicting evidence, if she wants. But from my perspective, it sounds very different. It sounds like researchers weary of simplistic fearful chanting about everything heating up, doing their best to clarify what they actually are seeing in climate trends.

Perhaps more importantly, I notice that a large part of the press release (and a significant part of the news item Kate linked) are concerned with the implications of these trends for water supplies for 50 million people in Pakistan. Whenever someone argues persistently with Kate about climate change, she falls back to her argument that resources should be used for adaptation, not for trying to prevent it. Here is a team of researchers working towards a sound method of predicting future runoff volumes into reservoirs, as the climate changes. What a fine contribution to the ability of those 50 million people to adapt - and Kate is bashing the news in order to score a point with her readers.

Am I wasting my time?

UPDATE: Speaking of time, I conclude that I have been too anxious about timeliness of posting, and it's time to put more work into the quality.

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