A scientist critiques VFR’s non-scientific critique of global warming

Paul Nachman writes:

At your entry on Phil Jones, you write:

But if the Medieval Warm Period was global, a possibility Jones acknowledges, then (1) the world has had warmer temperatures than at present within the last thousand years, without a catastrophe; and (2) modern industrial carbon dioxide emissions are not the cause of atmospheric warming. However, even without Jones’s concession regarding the Medieval Warm Period, his statement that there has been no significant global warming since 1995 is the nail in the coffin for AGW.

That’s not like you: As a matter of logic, your point 2 doesn’t follow. [LA replies: why doesn’t it follow? Since the medieval warming occurred before the modern industrial age with its vastly increased carbon emissions, the medieval warming was not caused by carbon emissions.]

Further, CO2 is absolutely a cause of atmospheric (or surface) warming. That’s the easy part of the problem. But other factors may overmatch CO2’s warming effect. [LA replies: What I meant to say was that factors other than carbon emissions have caused warming in the past, and therefore it’s entirely possible, even likely, that factors other than carbon emissions—such as sun spots—have caused the more recent warming.]

And Jones’s statement may be the political nail in the coffin for AGW, for awhile. But it’s not a scientific nail in the coffin. [LA replies: fair enough. For all we know, the repentant Jones is wrong, and there has been significant global warming over the past 15 years. However, when one of the top pro-global warming authorities states that the single most important datum on which the thesis of global warming has been based, namely the warming of recent years, hasn’t been occurring at all, then at the level of human common sense there is a reaction which says, “this whole thing has got to go back to the drawing board.” And that’s something for the scientists to do. As for the non-scientists, that’s not our concern. Our concern has been the political drive to push a supposedly scientific belief on the world in order to attain certain political ends. And that effort has been exposed as false and a fraud. Which is an event of historical significance in and of itself.]

When I took part in that discussion at your site, I recommended, in my last chunk, this long article. I expect that few followed up on my recommendation. If you didn’t, you should now. It’s by Richard A. Muller , a very “broad spectrum” physicist at Lawrence Berkeley National Lab and on the Cal-Berkeley physics faculty.

It’s a long chapter from a book he wrote for a course he teaches, and the chapter title is “Climate Change,” but, for present purposes, you could read just the first half, as the last half is about energy sources plus student exercises for the chapter. A reasonable stopping point would be after the very brief section titled

“Global Warming” vs. “Human-caused Global Warming”

There are about 8,000 words through that point. [LA replies: I’ll try at some point. But, as I just said, it’s now time for scientists—not non-scientists—to salvage which is valid from this mess. After they’ve done that, they can address the public again.]

When you read it, please keep going. There are likely points where you’ll say “Aha!” Mark them, and read on.

It was written in April 2008, so the news of the last few months isn’t reflected in the chapter; I expect he would change some of it now, but he wouldn’t throw the chapter away. Not a chance.

I’ve never seen Al Gore’s movie. However, I do have something to add to the discussion regarding Muller’s Fig. 10.9. If you’ve seen the movie, all the better.

Regarding what’s at your site on this subject, I think it’s time to tone it down. Climategate is about bad behavior, not the uncertain realities of the physical world. And on that, you should read Muller’s “Discussion Question” #1, after you’ve read whatever you’re going to read in the chapter.

I’ll reinforce what’s above with this quote from the someone at the Weekly Standard that I included in one of my prior responses at that earlier blog entry:

As tempting as it is to indulge in Schadenfreude over the richly deserved travails of a gang that has heaped endless calumny on dissenting scientists (NASA’s James Hansen, for instance, compared MIT’s Richard Lindzen to a tobacco-industry scientist, and Al Gore and countless others liken skeptics to “Holocaust deniers”), the meaning of the CRU documents should not be misconstrued. The emails do not in and of themselves reveal that catastrophic climate change scenarios are a hoax or without any foundation. [LA replies: Maybe not at the level of scientific proof. But at the level of human common sense, the global climate change scenarios are now established as a fraud.] What they reveal is something problematic for the scientific community as a whole, namely, the tendency of scientists to cross the line from being disinterested investigators after the truth to advocates for a preconceived conclusion about the issues at hand. [LA replies: Again, I’m perfectly happy to wait for that discussion to sort itself out. There’s plenty of time. I think the world will survive the five or ten years it will take for scientists to reach a more, excuse the wordplay, sustainable consensus on climate change.]

- end of initial entry -

A. Zarkov writes:

In his BBC interview, Roger Harrabin asked, “Do you agree that from 1995 to the present there has been no statistically-significant global warming,” and Phil Jones replied in the affirmative. In reading the back and forth between Mr. Nachman and Mr. Auster, regarding implications of Jones’s reply, I detect some possible confusion about what “statistically significant” means. I’d like to point out that the failure to establish statistical significance does not in itself mean average global temperature did not increase between 1995 and 2009, it only means the scientists cannot not reliably find it with the methods they use. As we all know, temperature varies tremendously in both time and place. Detecting a small trend over a short time can be difficult to impossible. The more variable the temperature was during those 14 years, the more difficult it is to detect a tiny trend. However in the political arena, failure to establish statistical significance could be devastating to the warmists. Without public support, Congress will eventually lose interest and stop funding global warming research. The public does not understand the nuances of statistical inference, and such remarks by Jones coupled with the ongoing IPCC transgressions will prove fatal to the whole “climate change” enterprise. I suspect Phil Jones is simply a rat leaving a sinking ship, and that’s why he’s breaking ranks. In the alternative, he’s just extremely naive. If one carefully reads his answers, he hasn’t said all that much from a scientific viewpoint, but that’s not how the public will read it.

LA replies:

In common sense terms, to say that there has been no “statistically significant” global warming means the same thing as saying that there hasn’t been global warming. If we say that a person has had a loss of weight, but not a statistically significant loss of weight, that means that the weight loss is so smal thatl it doesn’t mean anything and is not worth mentioning.

A. Zarkov writes:

Mr. Auster writes,

In common sense terms, to say that there has been no “statistically significant” global warming means the same thing as saying that there hasn’t been global warming. If we say that a person has had a loss of weight, but not a statistically significant loss of weight, that means that the weight loss is so smal thatl it doesn’t mean anything and is not worth mentioning.

He gives a good example, but I think it needs some clarification and extension. We know that most of us gain weight slowly as the result of a small difference between calories consumed and calories expended. We also know that our weight fluctuates from day to day, and it can take a year or more to see a noticeable weight gain. It would be helpful to be able to detect this slow gain way ahead of time, so as to take corrective action. Suppose I weigh myself every day for two weeks. Is that enough to predict my weight after a year? Generally no. I won’t see a “statistically significant” trend in my weight in that short a time with daily measurements. Yet I might be gaining enough weight each day (on average) to present a problem within a year. Note. As a practical matter unless we keep our eating habits fixed along with our activity, there would be almost no hope of detecting a weight gain in two weeks unless one were a real pig.

Finally, I don’t like the idea of statistical significance, because it’s a yes or no result. I much prefer a confidence range for the trend, so we can state probability of any specified weight gain. For some people a 10% probability of gaining 30 pounds in a year would be enough to take corrective action. Others would be willing to take the risk and not change their eating habits.

February 17

Dan K. writes:

You wrote: ” … I’m perfectly happy to wait for that discussion [on the true facts about warming] to sort itself out. There’s plenty of time. I think the world will survive the five or ten years it will take for scientists to reach a more, excuse the wordplay, sustainable consensus on climate change.”

Consensus has no role to play in science, really.

LA replies:

When we’re speaking of science as science, I suppose you are right. But the whole point here is that we are not dealing with science as science, but with science used as a basis for major political actions. If certain scientific findings are to be accepted as established and as the basis for major political actions by the society that will radical alter the nature of the society, it would seem that there would have to be a consensus that the science in this area is settled.

If there is no such consensus, or if none is possible, then that needs to be acknowledged, and henceforth appeals to “settled science” cannot be used to advance this particular transformational political agenda.

Posted by Lawrence Auster at February 16, 2010 11:17 AM | Send