A few weeks ago I criticized Senator Orrin Hatch for some of the statements he made in his web page, “Climate Change 101“. For all his talk about scientists needing to be more open-minded about criticisms, it turned out that Senator Hatch wasn’t really following his own advice. Instead of painstakingly evaluating the evidence (what truly open-minded people do,) it was apparent that he was willing to believe any arguments that seemed to support his biases–including arguments that were based on fabricated, but easily checked, data obtained from a non-scientist. This time I’m continuing the theme to show just how biased Senator Hatch really is about climate change, by examining some of his statements about scientific “hypotheses” and “proof”.
First, here’s how Senator Hatch introduces the subject of anthropogenic global warming.
Many scientists support the hypothesis that human-emitted CO2 is warming the planet. (Of course, scientist support for a hypothesis is irrelevant to whether or not it is true. Good science dictates that only observational evidence can support a hypothesis, but more on that later.) Human-caused warming is referred to as anthropogenic global warming (AGW). According to the AGW hypothesis, this extra blanket disrupts the balance between incoming and outgoing energy by holding in more energy than would otherwise be absorbed. The United Nations Intergovernmental Panel on Climate Change (UN IPCC) has claimed that most of the warming observed over the past century can be attributed to AGW. However, contrary to most media reports, there is not a consensus on this question, even among UN IPCC scientists (UN Climate Scientists Speak Out).
So when the subject is human-induced climate change, it’s just a “hypothesis,” which is an initial explanation that hasn’t yet been rigorously tested. And even though 97-98% of active climate scientists agree that humans are causing significant climate change, “there is not a consensus” on the issue, because SOME climate scientists (2-3%, to be precise) disagree.
This demonstrates some deep misunderstandings. When has a “hypothesis” been tested enough that it graduates into a “theory”? Whether Senator Hatch likes it or not, it’s when the scientists in the relevant fields decide the accumulated evidence is strong enough. It’s a judgement call, and in this case the vast majority of climate scientists have already judged that the evidence for human-caused warming is quite strong. There have literally been thousands of papers published about this. If you are interested in an overview, check out Ch. 9 (“Understanding and Attributing Climate Change”) of the latest IPCC Working Group 1 report. Also, the idea that 97-98% of the community doesn’t constitute a “consensus” is absurd. Science doesn’t EVER provide absolute proof of anything, so in all but the simplest cases it’s typically impossible to get 100% agreement. Scientists have all kinds of old sayings that make the point that some people just won’t let go of their doubts and move on with the rest of the community. “Old theories never die–their adherents do.” “And so science progresses, one funeral at a time.” And so on. If Senator Hatch is waiting for 100% agreement before granting that there’s a “consensus” that requires action, he is implying that we should wait forever to act on ANY issue scientists bring up.
Some readers who are inclined to defend Hatch might chime in at this point, saying, “Hey, there’s no standard written in stone about what proportion of scientists in the relevant fields have to agree before we can claim a ‘consensus.’ Maybe Senator Hatch is just a hard-nosed skeptic who requires more agreement than YOU do, Bickmore.” Fair enough, but as I pointed out last time, Hatch only seems to play the hard-nosed skeptic when dealing with arguments against his point of view.
Let’s look at another example. How much evidence does it take to convince Senator Hatch that the entire edifice of mainstream climate science has collapsed into a pile of smoking rubble? The answer is precisely one paper–one that has subsequently been gutted by the rest of the climate science community. Hatch wrote:
One of the Lead Authors of the IPCC reports is renown [sic] MIT climate scientist Dr. Richard Lindzen. He recently completed a study that explains why temperatures have remained steady or cooled over the last decade, while CO2 has steadily risen. His peer-reviewed study disproves the positive feedback hypothesis and, thereby, the accuracy of the UN’s models and the AGW hypothesis.
Wow. One paper, published in 2009, “disproves” the whole idea that humans are causing significant global climate change. Shouldn’t Hatch have at least given the rest of the climate science community a chance to respond before he logged the time of death? It turns out that now they have responded, and shown a number of glaring problems with Lindzen and Choi’s paper. For example, they cherry-picked their data, and attributed global significance to data that came exclusively from the tropics. See a summary with the relevant references at the Skeptical Science website. During a debate with Andrew Dessler, Dick Lindzen admitted they had made several mistakes in their paper, and claimed that he had written a corrected version that should come out soon. However that turns out, it is striking that Senator Hatch would pronounce the majority scientific view “disproven” on the basis of a single faulty paper that hadn’t yet been batted around by the rest of the scientific community, and yet, thousands of papers supporting the mainstream view aren’t enough to promote it out of the “hypothesis” category in his mind.
At this point even some scientists might object that while you can never prove scientific hypotheses, they must be falsifiable, so the idea that thousands of papers can’t completely verify a theory, but a single paper can falsify it, is maybe not so crazy. The falsifiability criterion was made popular by Karl Popper, the famous philosopher of science, but while falsifiability is still considered a useful concept, it’s 40-50 years out of date. Other philosophers of science, notably Imre Lakatos and Thomas Kuhn, used historical arguments to show that Popper’s falsifiability criterion was too idealized to describe how science is usually done. Real scientific theories generally are complex enough, and perhaps difficult enough to quantify, that a single experiment usually can’t take it down. The problem is that if an observation doesn’t agree with the theoretical prediction, it’s hard to tell whether the core of the theory is wrong, or just some auxiliary assumption. It usually takes a number of negative results, therefore, before scientists give up on a theory that has been reasonably successful.
Once again, I’ve given clear evidence that Senator Hatch hasn’t really done his homework about climate change. Instead, he has been willing to swallow any reasonable-sounding argument against the mainstream scientific view while holding the mainstream view to an impossibly high standard, simply because he doesn’t want to believe it. Climate change is too important of an issue to allow politicians to treat it in such a cavalier manner, and I, for one, think we should hold Senator Hatch’s feet to the fire on this one.