05 January 2010

The Biggest Control Knob

I've mentioned Richard Alley before, with good reason.  You can get a flavor of the reason by looking at his Bjerkenes lecture The Biggest Control Knob: Carbon Dioxide in Earth's Climate History.

It's about 50 minutes, and you can skip the introduction to save a little time.  One thing not to miss from the introduction, so I'll mention it here, is the title of Richard's popular book The Two Mile Time Machine.  In it, he discusses how we (he) figures out what climate was like from examining ice cores.  First hand discussion.

Digressing to the personal a second, I do know him personally.  I was a guest lecturer in the 1991 edition of the class he mentions.  My thing at the time being deep ocean circulation, with some concern about how that affected atmospheric CO2 levels.

Back to his talk; he says a few things that I think are particularly useful for thinking about how science is actually done.  At one point, he notes that good scientists doing good work come to one conclusion -- one which makes for a conflict between two sorts of data.  And there are other good scientists also doing good work, but differently, who come to an answer that shows no conflict between the two types.  Now, who's right?  We need to do more work.  It isn't that one group is bad people, or doing bad science.  There's a conflict in the results, so we need to learn more, which means do more work to understand how the conflict comes about.  Probably (my opinion) it means that there's a loophole in one of the sorts of analyzing the geologic record, so that it doesn't only record what the method expects.  Finding that loophole is the challenge.

You'll see, also, something about what scientists are like inside.  Most of us aren't as demonstrative about liking our subjects.  But nobody can watch Richard for more than a few minutes and not realize that he loves his subject.  The rest of us do, too, just not so obviously.

This all actually relates well to the post I promised in my last note.  It turns on looking at ice cores and CO2, and Richard will fill you in on parts of the story that surround the two.


Steve Bloom said...

Bob, I have to say I'm mesmerized by the confluence of recent papers relating to the Pliocene warm period (Lunt et al, Pagani et al, Robinson solo and Tripati et al). The latter is relevant to Richard's talk since I assume he was referring to it when he commented that the mid-Miocene CO2-temp discrepancy appears to have been largely resolved. Anyway, the firming-up of the CO2-temp relationship for the mid-Pliocene seems to me to be a topic deserving of a lot of attention, so any you're able to give it would be appreciated.

Robert Grumbine said...

Thanks for the reminder. After my day job, where 1 year is considered 'long range', I can use the reminder that 1 million years isn't at all an unreasonable period to look at. I'll probably start with some discussion of the carbon cycle, which I haven't taken up before and would like to get back up to speed regarding. And then in to the fun of thinking of 1000 years as a short time :-)