Sunday, August 21, 2005

The Bet

A few people have asked about the details of the bet I've arranged with Bashkirtsev and Mashnich. Both Jim Giles (Nature) and David Adam (Guardian) basically got it right, but here it is again in full.

  • We will compare global surface temperatures in 1998-2003 with those in 2012-2017 (6 year average in both cases), using the USA National Climatic Data Center data (which can currently be found here for annual and here for monthly analyses). (Update 13 Feb 2007: data seems to have moved to here.) (Update Jan 2010 now it's here)
  • If the temperature rises over this interval, B+M will pay me $10,000 (in total). If the temperature drops, I will pay them $10,000 (again, in total).

It really is as simple as that. There are no exemptions for volcanoes, large meteorite strikes or nuclear winter. I recognise that this introduces a small additional risk against me: such short-lived perturbations could cause a few years of anomalous cooling in an otherwise warming trend, but I can't think of any corresponding external forcing event which could cause a few years of anomalous warming (El Nino could have a modest effect). There is also no allowance for anthropogenic emissions, as any plausible changes in these can hardly have an effect over such a short interval, even if one accepts that they have a significant effect at all (which B+M presumably would dispute). There is also no explicit agreement as to what we should do if the NCDC ceases to exist - I would expect to transfer to another near-equivalent body (eg CRU in UK, NASA GISS - there is virtually no chance of any of these disagreeing on the sign of the temperature change).

At the moment, this bet is essentially a "gentleman's agreement". B+M (M, in particular, CCed to B) expressed their acceptance of the bet over 2 emails to me, and also confirmed this directly with Jim Giles. I suppose it would make sense to actually exchanged signed bits of paper about it (and will try to arrange this), but I suspect that in the event of a default, chasing such a modest gambling debt internationally through the courts would be effectively impossible anyway. I'm also confident that B+M are honourable and honest people who will not try to wriggle out of paying up if they lose. Note that the loser will almost certainly see it coming a few years off and have a long time to save up.

Obviously, for a proper futures market, it would be necessary to pay up-front to a recognised market, where the money would have to be invested in a sensible (interest-bearing) place and controlled by a trusted third party who would eventually also judge the bets. At the moment, none of the obvious on-line betting markets seem interested due to the time scales involved, but I haven't given up hope.

14 comments:

Coby said...

That's great! If ever you want someone to back you up because you get too many offers, I'll gladly take a piece of that action!

On the PR front, this is actually a set back. Your point is much better made when no septic dares step forward. Anyway, by 2018, even junkscience.com will have quit beating this dead horse so your win will only be an historical chuckle...

Still, the refusal of Lindzen, Singer and Milloy to step up to the plate is a fine proxy for their integrity.

James Annan said...

On the PR front, this is actually a set back. Your point is much better made when no septic dares step forward.

Well, I do realise that at the moment the "market forecast" is for zero warming, which is in itself very sceptical. But that is of course based on a very thin market (1 deal) and, PR points aside, I'd actually like to see what a real market would say. Eg in my view, the GW2030 claim is excessively alarmist at +0.24C/decade of warming over 30 years.

Brian said...

I wouldn't call it a PR loss - the agreement draws attention to the consensus position and to the fact that the majority of denialists refuse to back up their position. There will be still more publicity when B+M pay James. As Martha Stewart says, it's a good thing.

Johan said...

Is solar activity predictable for the next 10 years? The Russian scientists obviously expect it to decline.

James Annan said...

Solar activity seems to vary in regular cycles. I'm not sure how much of that is understood, versus merely observed in that, but I do not dispute the fact itself. The point I do disagree with is not that the effect exists at all, but that it can overwhelm the anthropogenic influence.

Tom Adams said...

First, your link to the yearly data above is broken. I used a simiar dataset from the directory.

I was exploring the idea that you made a bad bet because the 1998-2003 period was anomalously high.

If the underlying rate of GW is about 1.5 degrees C/century for, say, the period 1980-2017, then you made about an even bet.

At the rate of 3 deg. C/century, you bet is very good.

What do we think the current rate is? I know 3 deg. C/century is near the IPCC estimate looking forward. But, what is the current rate, or the rate during the period of this bet?

James Annan said...

Tom,

The forecast rate is roughly 0.2/decade. Even though I included the 1998 El Nino in the start period, it will be a big shock if there is no warming at all!

Tim Worstall said...

Got your checkbook?

http://www.longbets.org/faq

They offer the third party investment bit but the winnings have to go to charity.

James Annan said...

Tim,

I'm aware of longbets.org. If you want to give some money to charity, go ahead, but I'm not really interested in a pointless gesture where the outcome is the same for winner and loser.

Hank Roberts said...

> none of the obvious on-line
> betting markets seem
> interested due to the time
> scales involved ...

Did you ever ask the Canadian DeSmogBlog people if they, er, might know somebody?

Don't get near the USA with this question, obviously.

Brian said...

The ftp sites aren't working right now, not sure if that means they've gone kaput.

James Annan said...

Oh, they'll just have changed the directory structure, which seems to happen quite frequently (GISS did the same at least once). I'll have a look around...

James Annan said...

Found again!

Hank Roberts said...

Cross-reference:
http://backseatdriving.blogspot.com/2010/01/climate-betting-baseline-set.html