Monday, September 14, 2009

Listen to me (being vaguely alluded to) on the radio

The latest More or Less has Andrew Gelman being politely dismissive of some extremely dodgy work on sex ratios that he has blogged about a number of times (and written some papers).

There was also a bit about climate prediction. Mojib Latif has got himself in the news recently with some comments about his prediction of short-term cooling which of course the denialosphere loved. He's part of the Keenlyside et al team, but I'm far as I'm aware there is no new research behind his statements which were made at a big political meeting. I don't think anyone believed the Keenlyside et al work when it appeared, and the Pope (ha) put the boot in ever so gently, describing the work the Hadley Centre had done (that I mentioned some time ago) to show that the method that Keenlyside et al used doesn't work.

Oh yes, as for the vague allusion to me, if the promised El Nino lasts over the winter then I should have a good chance of collecting on the bet I made on More or Less last year. Not that it's a sure thing or anything. I'm in with a reasonably good chance here too - if the current melt continues for another week I'll be in the money...


skanky said...

More on Latif here:

Including a link to the audio of the talk itself.

crandles said...

Hmmm I week of decline at the same rate (95k Km^2) as the past week would get us down to 5154k Km^2 and you need it down to 5121k Km^2.

Not impossible to happen within a week or just after one week. However, I am suprised the area minimum hasn't already been called and the rate of decline would be expected to reduce. A 2003, 2005 or 2007 like Sept extent pattern of decline would do it for you but you seem to keep switching in and out of being too optimistic about your chances at the lemming lounge.

3 out of 7 certainly sounds reasonable but do we really expect 2007 like pattern and 2003 only does it because 13 Sept 03 was higher than 11 Sept 03 by 139k Km^2 which isn't true of 2009. So removing those 2 years leaves 1 in 5 which is more like the odds I would suggest. (Perhaps that is still reasonable?)

James Annan said...


Thanks for the link. I do think Latif is making a bit of a meal of it, even if the media is making it worse.


Well in my defence I was mostly joking - especially with the older comment, when it would have been ridiculous to have been really that confident. But it would have looked good if it had played out :-)

But then melt seemed to have slowed down markedly, spending 8 days in the 53xx range. However then it sped up again to ~20 k km^2 per day for 4 consecutive days (though yesterday, which was down to 5240 when I wrote this post, has been adjusted upwards). So when I wrote the post, another 6 days at 20k km^2 would have worked for me.I haven't looked carefully enough to have much of a feel for how smooth the minimum generally is.

crandles said...

Seems like a good example of cherrypicking the start with a 4 day period for 'currently' when the sentence mentions a week combined with a incorrect end point using inconsistent data when there is a pattern of big falls with first data point which is then revised to a smaller fall with the later consistent datapoint.

With all this, anyone would think you had been picking up tips from the septics ;o)

James Annan said...

If you can't beat them, join them :-)

Actually I was unaware of the numbers getting revised. Still, I'm not going to be far wrong. In fact I'm already within the 95% interval of my prediction, albeit someone else is closer.

skanky said...

"even if the media is making it worse."

Or more specifically, Fred Pearce, on whose report it all *seems* to be based.

crandles said...

Revised might be the wrong word - it may just be two differently timed readings.

So much for the pattern of a big fall then a rise - the next 'big fall' is an increase of 20k. Ho hum.

Makes it look more like Hypocentre win at the lemming lounge though.

I thought the twice a day readings had been mentioned at the lemming lounge by more than just me in my recent post.

James Annan said...

Ah, Pearce. No surprise there then.

Steve Bloom said...

Aha, so Fred has some form. The quote from Vicky Pope in the same article also seemed strange. How is saying that the recent Artic sea ice trend is influenced by both natural and anthropogenic factors even slightly novel or controversial?

James Annan said...


I'm a bit surprise you aren't leaping to his defence, but IMO Pearce is one of the worst over-hypers (frequently in the Indescribablyoverhyped, now sadly about to fold), and I don't think his approach is sustainable in the long term.

As for sea ice...well the models also have their own natural variability, so the question is to what extent the recent extreme lows are a problem with variability versus bias in the forced response. There has certainly been a fair amount of press (and indeed peer-reviewed science) pushing the latter angle.

Steve Bloom said...

I probably should have been more aware of Pearce's record, but my media tracking quota is pretty well taken up by following the prominent U.S. reporters (e.g. Revkin and Eilperin) and my local outlets (SF Bay area).

I take your point re the contribution of natural variability to the recent Arctic sea ice decreases, but is there anyone who has claimed (in a peer-reviewed context) they can confidently exclude it (bearing in mind the difficulty of disentangling in turn anthropogenic influence from natural variability)?

But now I will defend Fred a little: Like all science journalists, he struggles with how to fit the long-term problem of climate change into the short-term frame of the human attention span. As there doesn't appear to be a solution to this problem, I feel compelled to forgive him somewhat (although that's not the same as cutting him slack on mistakes).