29 July 2011

Odds and Ends -- July 2011

A number of interesting items that are a little more time-related than I normally talk about.

Some sociology for amusement:
Nation's Climatologists Exhibiting Strange Behavior h/t Michael Tobis.

Regarding some of Roy Spencer's latest Well, give me more than 30 parameters, and I can fit a trans-dimensional lizard-goat ... by Barry Bickmore. I've downloaded the other recent paper and will take it up as my time and interest permits. A couple people have already asked about this, so read Barry's notes in the mean time.

Some fun science, and a reminder to beware of gifts bearing Greeks:
Phil Plait on Earth's first Trojan Asteroid
... and the NASA press release on it.

Trojan asteroids do not, it turns out, contain Greeks. Apparently that is limited to a horse in the Iliad. What happens is that if you have two bodies that are very much more massive than a third, like, say, the Sun and Earth compared to an asteroid, you can park an asteroid on the earth's orbit, but 60 degrees ahead or behind. And it will pretty much stay there. The 60 degrees ahead or behind are called the 'Trojan points'. We've long known of bunches of Trojan asteroids for Jupiter. As Phil's title suggests, this is the first time we've found one for the earth.

That's a bit about the doing of science: There was every reason to believe that the Earth had trojan asteroids. It would actually have been quite remarkable if we didn't -- gravity is supposed to work the same way for us as for Jupiter (allowing for the fact that we're so much less massive). Still, we're happier to see what we expected.


Alastair said...

The problem is that Roy Spencer is known to be a creationist and a non-believer in the dangers of global warming, so what ever he says is disregarded, but in this case he is correct. Clouds do produce a negative feedback on rising temperatures. That is what has kept the climate stable over the last ten thousand years.

But what if increasing carbon dioxide can take the global climate over a tipping point where we return to the ice free northern hemisphere which existed 2 Ma ago during the Pliocene?

Clouds adjust to maintain the planetary albedo but what will happen if the Arctic sea ice disappears. Will the clouds then be able to to maintain the climate at its current state? It only takes a simple 0D models to see that this is not the case.

You can't remove the effects of the sea ice albedo and still get the same mean global temperature.

Robert Grumbine said...

I don't think Spencer's creationism is much known outside the blogosphere, and even there it is only the last few years that it became known.

Regardless of that, I'll suggest that his record with the satellite temperatures has more to do with any bias regarding his comments. Having worked on it for 20 years now, every new version has shown greater warming in the previously analyzed version's period of record. For years after an updated version that showed warming, he continued to leave posted an analysis that showed cooling. And so forth. Making errors is part of doing science. When all your errors for a long period go in the same direction, and it just happens that they also go in the direction of your loudly stated personal preferences for what you want the conclusion to be ... scientists get leery of that source. And should -- it's hard enough to do science when you're only dealing with random mistakes in source papers.

I've downloaded the paper myself and will be taking a look at whether there's anything there I can do something interesting about in a post here. In the mean time, I find certain amusement in the fact that Roy Spencer's model, yes model, is being so loudly touted by sources that have spent the last 20 years proclaiming that models are worthless.

Alastair said...

Spencer's work still seems to be producing controversy.

Robert Grumbine said...

I don't think I follow you Alastair. Spencer is cited there only for historic purposes. In the 90s, there was indeed controversy, as he was finding a cooling trend where others found warming. Early 2000s, though, this controversy evaporated as a long series of errors he had made were found and eliminated. Had he not made those errors, there never would have been a controversy.