Speaking before an audience of journalists in Aspen last week, the former Veep called B.S. on a number of assertions often made about climate change. Since then, there's been a lot of the typically polarizing blather that Gore both decries and commits, but not a lot of hard analysis of his claims and rhetoric.
The speech was vintage Gore, with ambiguous grammar making it very hard to understand what he really said. I invite readers to grade the six assertions he made, and you will find that it's pretty subjective. If you're old-school and allow for no wiggle room, he flunks. If you give partial credit, he may do very well, depending on your reading of what he really meant. Give it a try.
You can hear the 1:15 minute audio of his litany here. The first B.S. call is on people who say "man-made CO2 doesn't trap heat." Unlike what follows, this is a clear, declarative statement, and he's right. I don't know who of us cringes more when we hear that carbon dioxide isn't a greenhouse gas.
But things soon get murkier. The next words are: "It may be volcanoes [expletive]." Strictly speaking, the antecedent to "it" is what "traps heat." Anyone who says that volcanoes are more responsible than man for increasing carbon dioxide is stating an easily testable hypothesis. There should be a jump in atmospheric CO2 after a big eruption. Not. If that's what he meant, it's B.S.
But "it"s not exactly clear what Gore is referring to. If "it" is generic for volcanoes being a factor involved in global warming, that's not BS. Just look at today's issue of Science, where Susan Solomon provides evidence that about a third of the post-1998 warming predicted by models that don't factor in volcanoes (i.e. almost all of them) is in fact being prevented by them.
This becomes the grader's call. I'll give Al half credit.
Next comes "it may be sunspots [expletive]." Judith Lean and David Rind, two scientists of Gore's preference, recently calculated the contribution of a standard sunspot cycle to climate. Going from a maximum, which we were in during the late 1990s, to a minimum, where we are near now, cools things about a tenth of a degree. That's certainly explanatory for the last decade but not nearly sufficient to explain the past century. Nicola Scafetta from Duke thinks the solar contribution may be three times larger.
And if Gore means solar modulation of warming in general, there's a research thread emerging that cosmic ray fluxes, which are modified by solar activity, can influence cloudiness and therefore climate. While I am personally very skeptical of this, it's obvious that there is just too much conflict out there to call B.S. on anyone who says the sun is important. Half credit again.
This section then ends with "it's not getting warmer [expletive]". That depends on your time frame. If you choose to look at the last 15 years, it's not B.S. If you go back to 1976, when the second warming of the 20th century started, it is. Too murky to call B.S., too unclear to not do so. Another half-credit.
At this point the wheels come off his wagon. Consider his words (emphasis added) "There is no longer a shared reality on an issue like climate."
What does he mean? Did everyone once agree that fighting climate change should be, as he wrote in Earth in the Balance, "the central organizing principal for civilization"? Clearly not. (Citation: Nov. 7, 2000). Is there a shared scientific reality about the magnitude of future climate change caused by human activity? Heck no.
Everyone, on the spectrum from the United Nations to MIT's Richard Lindzen, acknowledges that the magnitude of future warming is uncertain because of the unknown true "sensitivity" of surface temperature to carbon dioxide changes. This is highly dependent upon how much warming self-amplifies or self-damps, and how efficiently the earth dissipates excess heat to space. Wrong because of improper premise.
Finally, the corker, that "the very existence of our civilization is threatened" by climate change. If this were a graduate student paper, I would write, "citation, please?" "Civilization" is a big word, as in "Greek" or "Roman", and I think "our" means "Western", which is remarkably insensitive to environmental disaster and change. The worst weather imaginable boggles GDP by a couple of tenths of a percent. On a planet that was about a degree (C) cooler, life expectancy in our civilization was half of what it is today. The overwhelming evidence is that people in vibrant economies adapt to, or, like Gore himself, profit from change. How much did he make on his carbon-trading business? What's his speaking fee? Wrong on the merits.
So, in six B.S.-related assertions, Gore got one absolutely right, got half-credit for three others, and two wrong. A lot of points were lost because he did not define his time frame and used a very ambiguous pronoun. That may have been unintentional, given that his remarks were unscripted. But while it affected my grading, I'm interested in what others have to say.