Friday, March 14, 2014

Hot and Cold

“42.7 percent of all statistics are made up on the spot.”
—Comedian Steven Wright

Last Monday twenty-eight Democratic senators held a talkathon in order to raise awareness about the threat of climate change.

“Despite overwhelming scientific evidence and overwhelming public opinion, climate change deniers still exist,” said Majority Leader Harry Reid. “They exist in this country and in this Congress.”

Reid might want to take another look at public opinion. According to the Gallup organization’s website, a recent poll “puts climate change, along with the quality of the environment, near the bottom of a list of 15 issues Americans rated in Gallup’s March 6-9 survey. The economy, federal spending, and healthcare dominate Americans’ worries.”

Why such a disconnect between what so many politicians say and what most ordinary people think?

And it’s not just politicians who are sounding alarms about climate change. Most of the journalists that most people are likely to read or hear treat the issue of climate change as a very serious one. Every so often discussions can be heard on media-watching programs like public radio’s On the Media about whether journalists should even give print or air time to people disputing climate change orthodoxy since the debate on the topic is so clearly over.

But if the debate is truly over, why do all those senators need to stay up all night talking about it? After all, the surest way to know that a debate is over is to not be hearing people all the time still trying to get people to agree with them.

Part of the problem is that, as with so many contentious issues, people’s careless usage of the language (sometimes deliberately, sometimes lazily) confuses things. First off, let’s stipulate that the climate is changing. You’d have to be pretty dense to argue otherwise. After all, the earth’s climate has always been changing. If it had actually stopped changing at some point, I might well be living under glacier today. So the climate change debate—which may or may not be over—is not actually about whether the climate is changing.

And how is it changing at the moment? Well, let’s take a look at the best temperature records we have at our disposal. They indicate that we are in a warming trend that has been going on since the early 17th century, i.e. since the so-called “Little Ice Age” began to abate. The current warming trend has yet to reach the temperature level of the previous warming trend, which peaked around the year 1300. That one reached higher temperatures than the previous one, which peaked during the Roman Empire, but did not reach the temperatures of the one before that, which peaked around 1100 B.C.

It is worth noting that the current warming trend is, for the moment, on pause. Temperatures have effectively plateaued for the past decade and a half. People on one side the debate—which may or may not be over—argue (correctly) that this does not necessarily mean that the warming trend will not continue. People on the other side of the debate argue (also correctly) that this does not necessarily mean that the warming trend will continue. The latter people also point out (correctly) that the computer models cited by the other side did not predict the current pause. So when Harry Reid lashes out at “climate change deniers,” he is attacking people for denying something that not only hasn’t actually happened but is, in fact, just an educated—and occasionally revised—guess about what will happen.

The argument gets complicated because each side can—and does—come up with its own “trend” by cherry-picking the span of years that best supports its argument. And then there is the eyewitness evidence. Melting glaciers and shrinking ice cover make dramatic impressions, but only when we lose sight of the fact that there is much more to climate than average global temperatures and, again, each side cherry-picks its examples. Neither side is above using extreme short-term temperatures (summer heat waves, winter polar vortexes) to argue its case. But then, as a counter-argument, each side will then proclaim (correctly) that short-term fluctuations are pretty irrelevant in the grand scheme of things.

But the climate change debate is further complicated in that it is a two-part proposition. The first question is whether global temperatures are rising. If they are, then the second question is, what is causing the warming? Let’s stipulate for the sake of argument that the warming trend will continue and even accelerate for the foreseeable future. Then what? Our Democratic friends in the Senate tell us that the warming is caused by the amount of carbon dioxide released into the atmosphere due to the burning of fossil fuels.

How do they know this? The “overwhelming scientific evidence” that Senator Reid cites is a reference to the oft-heard assertion that there is 97 percent scientific consensus on the issue. Where exactly did this consensus come from? If you trace it back to its origin, we find that there have been a series of surveys that always seem to arrive at the 97 percent consensus. The most recent is by former National Science Board member James L. Powell. When we look at Powell’s website, we find that he arrived at his number not by polling scientists but by counting scientific papers that he found by searching on certain keywords and then making a judgment as to whether or not each paper supported the notion of anthropogenic, or man-caused, climate change.

Powell did not approach his survey from a neutral position. As his website makes clear, he is an ardent campaigner on the issue and has written on the topic for The Nation. So it is probably not surprising that his survey apparently did not find anything written by the 31,487 scientists that signed a petition that read in part, “There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gases is causing or will, in the foreseeable future, cause catastrophic heating of the Earth’s atmosphere and disruption of the Earth’s climate.” When this is brought up, the other side rejects it on the grounds the petition’s signers come from a wide number of scientific fields and not specifically the field of climate science.

One climate scientist who disputes the notion that global warming currently poses a grave risk is Richard Lindzen of MIT. In January he was questioned by a committee of the British House of Commons about an assessment review from the Intergovernmental Panel on Climate Change (IPCC). When asked about the climate change consensus, he said, “[T]here is so much penalty for saying that this is not an important problem that I don’t think people would go out on that limb…”

He continued, “You look at the credentials of some of these people and you realize that the world doesn’t have that many experts, that many ‘leading climate scientists.’” Committee chairman Tim Yeo asked if he was actually suggesting that climate scientists were somehow academically inferior. Replied Lindzen, “Oh yeah. I don’t think there’s any question that the brightest minds went into physics, math, chemistry…” Ouch.

I don’t know who’s right in the climate change debate, but I do know that it’s pretty clear that the debate is not over. And you can usually tell who is losing a debate by seeing which side wants to proclaim the debate over. And also by Gallup polls.

Dr. Lindzen may well have been unfair to the community of climate scientists. But it is worth bearing in mind who pays them. After all, there used to be a lot of scientists who kept finding that smoking had no harmful health effects. Their funding came from tobacco companies.

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