For those who haven't made it their business to memorize the bet details, they're here:
We have three bet periods -10, 15, and 20 years - and two bets for each period - an even-odds bet and a 2:1 bet in David's favor. The even-odds bet centers around a temperature increase rate of 0.15C/decade with a 0.02 void margin on either side (bet voids if temps increase between .13 and .17C/decade). The 2:1 bet centers on 0.1C/decade with a .01 void margin. Even-odds bets are for $1,000 each, and the 2:1 bets increase over time, with me betting $1,000, $2,000 and $3,000, and David betting half that. My exposure is $9,000; his is $6,000.
Temps from 2010 through 2014 won't directly affect who wins, although they'll give an increasingly good idea of who's likely to win (note though that because 2005 was the GISS record and included in the 2007 five-year average, the 2008 average will only be higher if 2010 is a new record). With the baseline established, our two bets each for 2017, 2022, and 2027 averages are centered at .6C and .7C above the 1951-1980 period for 2017; at .65C and .775C for 2022; lastly at .75C and .85C for 2027.
The other (and original) significant-money bet was between James Annan and two Russian cosmologists, where the Russians predict cooling. I thought I'd look at how it's going - a slightly different data set, 6-year average, baseline set at 1998-2003 and compared to 2012-2017. I'll just be lazy and compare to the 5-year GISS averages in the links above. 1998-2002 is .45C above baseline, and latest five-year average, 2005-2009, is .55C. For the Russians to win, they need temps to start declining soon, and fairly dramatically. James can start making plans for his $10,000, I think.
And there's William "Always the Bridesmaid, Never the Bride" Connolley who hasn't been able to arrange any big bets on warming. Lots of small ones though, including one against me for $10 that he won but I think he's forgotten about, and I'm not going to remind him.
I've had a couple of nibbles for bets, but nothing's worked out - I could probably try a little harder to make them work, and might try and revive some prospects.
Not much else on climate betting that I've heard. Nate at Fivethirtyeight.com wrote in favor of climate prediction market, and argued it's unlikely to be manipulated by people placing bad bets in order to support their political arguments. I agree, on the basis that it wouldn't take too much money against us to tap out me, William, and the few others who are out there taunting denialists to put their money where their mouths are, but no one's done it. Too bad.
UPDATE: Crandles points out in the comments that he won $1300 betting on 2009 being one of the five warmest years at Intrade. Some other interesting bet options there, maybe.....
UPDATE: Crandles points out in the comments that he won $1300 betting on 2009 being one of the five warmest years at Intrade. Some other interesting bet options there, maybe.....
Interestly as a skeptic, I've challenged many alarmists, and they have all refused.ReplyDelete
One of the questions relates to how to arrange the bet to be fair, or to give correct odds.
It's an interesting question because it goes to the heart of how to make a prediction and test it.
That's why Realclimate is hilarious at times.
There argument goes like this. Look at the fit between prediction and reality.
So when did you make the predictions?
About the middle to right hand side of the graph.
Isn't that a bit like betting on a horse race after it has started?
Why's that important? Just look at the fit....
You can't argue with idiots like that. It's best to ignore them
I'm willing to make a fairly simple bet, that temps in the next decade will not only keep going up, but will go up at twice as fast as the per decade rate of the 20th Century. I think that's a pretty good test of AGW - after all, why would temps go up at a greatly accelerated rate after 160 years of warming? If it's just recovery from the Little Ice Age, we're more than recovered now and the increase should slow down or stop, not accelerate.ReplyDelete
So we might be in disagreement here.
Not at all Brian.ReplyDelete
The claim of GW is that the background trend has accelerated.
However, the evidence isn't that there is upward kink in the graph, its that any upward change is totally caused by anthropogenic causes.
With the change to climate change, its that any change in climate must be anthropogenic.
It's not that its hypothesis, predict and test any more.
Some new sort of science that doesn't have to do proof
AGW has a reason for the accelerating warmth. No other theory does. I think it's a good predictive hypothesis that the accelerated warmth will continue at the accelerated rate, then.ReplyDelete
Natural variation is another theory that explains the change.
The problem is that to disprove the simple theory (natural change), you have to show something that is unatural.
To show something that is unatural, you need to show that the current change is unprecedented. That means a long and accurate temperature record prior to 1880 or the start of significant anthropogenic CO2 production.
It doesn't exist, which is why the alarmists like to start their graphs then To dodge the issue of unprecedented.
ie. It's back to the test or the bet (same thing). No statistical test because of lack of data, and no proof.
The instrumental record starts in mid-late 19th Century. It's your side that screams about proxies for early periods and claims they're inaccurate.ReplyDelete
The current warming doesn't need to be unprecedented in the 4.5 billion year earth history, it just needs to be unexplained by natural forces. Natural forcings don't explain the warming, and a huge coincidence of tremendous warming just as we're increasing a gas that's been acknowledged to be greenhouse gas for 150 years, isn't plausibe.
But that's not what is being claimed.ReplyDelete
The claim is warming since late 19th century, and it must be unnatural.
You claim natural forcings don't explain it, but you have no evidence for that.
You need to have evidence as to what the rates of natural temperature changes can be without any anthropogenic CO2.
Since you don't have the records, you can't substaintiate that claim.
You need both pre and post industrialisation records to ask the question, is the current warming extraordinary.
What's your evidence for it being extraordinary?
The models demonstrate little warming to slight cooling absent human-caused forcings. The models don't accurate describe present or past conditions unless human forcings are included.ReplyDelete
Again, CO2's large and measurable effect has been known since the mid-1800s. Only when it became politically inconvenient was it then disputed.
Take two graphs.
Take it that any AGW starts 1910. ie. When the concentration rises to a sufficient level to start anything if you believe the litany
Now, lets look at sea level measurements (suspect anyway because they don't tie up with rotation times).
The rise started well before CO2 started rising.
Now, lets look at the claims.
1) CO2 causes the rise. Here you have to show that the natural rise stopped when you claim CO2 causes sea level rises. You also have to show what was causing the rise before.
2) Alternatively, since I can't see any acceleration corresponding to the CO2 levels, the null hypothesis, justified by Occam's razor applies and the non anthropogenic trend prior to CO2 rises has continued. I certainly can't justify why its stopped.
There was some natural warming post-1850 that combined with CO2 rise. Natural warming was predominant first, so it could cause the early sea level rise.ReplyDelete
As for not seeing any acceleration, look again - it's in the increasing curve of the tinyurl you provided. What skeptics can't provide is an explanation of why now, long after we've completely bounced back from the Little Ice Age, would the warming accelerate.
It's not accelerated significantly. However the alarmists are claiming all the rise as being anthropogenic. ie. The sea level rises has an anthropognic cause.ReplyDelete
You've just admitted that this is over and above some trend.
As for the warming accelerating, let me turn it round. The MWP is clearly there, however, you can't explain why it got cooler after the MWP. You can't explain why the MWP was warm. However, I can. It's natural variability.
The same is true for the majority of the current warming. It is well within the limits and rates of change from the temperature record. That means, by Occam's razor, there is no need to invoke another mechanism.
So in order for you to show something unnatural, you have to say what natural warming rates can be (degrees per year) and ask is if the last 100 years years warmed unnaturally quickly. You also need to show that the current temperatures are unatural. ie. We haven't seen them before. Included in this is also why current temperatures are being adjusted.
Temp has accelerated significantly, from .06 to .15C/decade. And your own chart showed sea level rise accelerating.ReplyDelete
There was a natural trend from 1850 to sometime in early 20th Century. The rest is artificial.
Since we don't even know if the MWP was global, there's little ability to compare it to modern warming. But yes, to the extent MWP did happen, I can explain it. It's natural variability.
The same isn't true now. We have the simple math and the complex computer models to prove it.
And I have my willingness to bet that warming will accelerate. My bet is that warming will be twice the 20th Century rate. Even if the 20thC rate could be thought of as natural for some insane reason, a "natural" warmer would have every reason for wanting to bet me when I'm willing to say the rate will continue at twice the pace.
>"Not much else on climate betting that I've heard"ReplyDelete
I obviously haven't been posting enough on my $1330 win on 2009 being in the top 5 years per GISS through intrade. Intrade is now running more and longer bets eg 2019 .2C greater than 2009, 2019 greater than 2009, years upto 2014 in top5 temps, 2010 warmest, 2011 warmest.
Good stuff crandles! Got a link for the Intrades bets? (Suppose I could lift a finger and look myself....)ReplyDelete
here is an open source calculation based on real temperature stations. Betting on the status quo is the safe bet http://www.bestinclass.dk/index.php/2010/01/global-warming/ReplyDelete
I don't seem to be able to link directly to them.ReplyDelete
select climate and weather on left hand side second section down
This will probably look horrible but:
BQty Bid Offer AQty Last Vol Chge
1 51.1 79.9 2 69.9 14 0
1 30.0 - 0 98.0 1 0
3 15.4 - 0 95.0 1 0
20 32.0 38.0 7 31.0 126 0
10 30.0 40.0 10 - 0 0
20 68.5 69.0 5 66.0 205 0
10 60.0 70.0 10 55.0 15 0
Complex models are not proof.ReplyDelete
What simple maths?
So far you haven't said what a natural rate of increase has been in the past?
For example take the IPCC predictions. For most of them we are 95% certain they are wrong.
see http://rankexploits.com/musings/ for details
The simple maths are what Arrhenius did in 1896. Tamino did a more modern version here:ReplyDelete
Yes, complex models are proof, especially because skeptics can't produce a climate model that works the way they want the climate to work.
I don't know what the maximum rate of natural increase has ever been in the past, but I do know the natural bounceback from the LIA in 1850 was much slower than the current rate of warming, and that generally even the changes from ice ages to interglacials is slower.
Your link to to the IPCC being wrong isn't very specific.
Crandles - have you written up details about your betting anywhere? If not, and you feel like it, send them to me and I'll post them.ReplyDelete
Yes, complex models are proof, especially because skeptics can't produce a climate model that works the way they want the climate to work.ReplyDelete
Not true. The skeptic model is that the rate of change (and particularly any acceleration) is well within the rates of change from the records (reconstructed).
Ditto that the extremes of temperature, sea level rises etc, are also at levels that have been seen in the past.
ie. No need to invoke any extra factors to explain what is going on.
The comparison of model predictions to actual temperatures shows that for almost all the predictions they have been proved wrong at the 95% confidence level. See Lucia's site for the details.
The last part is the really interesting part, because it relates to how bets are constructed.
I'm interested in the bets you have made and how you think the odds are fair on the results?
ie. From your post, its not clear how you are measuring the increasesReplyDelete
Saying any natural rate of change that has ever happened before is the explanation of the current warming, is totally inadequate. Past changes had something causing them, like CO2 overloads from snowball earths, or (possibly) massive methane clathrate releases. What's causing the accelerated rate now? Simply waving your hands and saying it's happened before isn't science.ReplyDelete
Re lucia's site, again, I'd like to see a specific link. I'm not going to read everything she wrote.
My bets are here:
As for fair, I try to pick an outcome that's somewhere in between what I expect and what a skeptic would expect would happen in the next 20 years, and bet over that. You seem to be arguing things could continue to warm at the present rate, which is twice the 20th Century rate, or maybe even faster, and still be natural. I see no difference between our predictions that would allow for betting with you, if that's your position.
David and I are measuring increases based on GISS data.ReplyDelete
Well, you did say that the trend has accelerated from the natural back ground rate.ReplyDelete
I was wondering how you factor out the natural in order to make a bet on the existance of the anthropogenic?
Phil Jones interview, of the criminal FOI set.
A - Do you agree that according to the global temperature record used by the IPCC, the rates of global warming from 1860-1880, 1910-1940 and 1975-1998 were identical?
An initial point to make is that in the responses to these questions I've assumed that when you talk about the global temperature record, you mean the record that combines the estimates from land regions with those from the marine regions of the world. CRU produces the land component, with the Met Office Hadley Centre producing the marine component.
Temperature data for the period 1860-1880 are more uncertain, because of sparser coverage, than for later periods in the 20th Century. The 1860-1880 period is also only 21 years in length. As for the two periods 1910-40 and 1975-1998 the warming rates are not statistically significantly different (see numbers below).
I have also included the trend over the period 1975 to 2009, which has a very similar trend to the period 1975-1998.
So, in answer to the question, the warming rates for all 4 periods are similar and not statistically significantly different from each other.
Now this is really important. Jones is one of the key alarmists, and here he is stating that the rate of increase is not unprecendented, when you compare the non-anthropogenic era against the so called anthropogenic era
I'm taking the 20th Century as the "natural" rate of warming. I don't believe it's natural, I think it's primarily anthropogenic, but that a skeptic would argue it's natural. I don't see why a skeptic would think that natural rate would suddenly double, 160 years after the "natural" recovery from the LIA when we've mostly recovered or completely recovered from the LIA. Therefore, a bet that warming will proceed at twice the 20th Century rate should seem attractive to a natural warmer as well as to me.ReplyDelete
We're repeating ground here, Nick. And again, what caused the warming from 1975 to 1998? Just because it warmed before doesn't mean the warming should continue. And I'm willing to bet it will warm at twice the rate that it did.
Here are the main alarmists claims. Dispute them if you think they are wrong.ReplyDelete
1. The current rate of change is unprecedented.
2. The current temperatures are above those in the past.
The implication from 1 and 2, is that if we can't think of a mechanism that is natural it must therefore be man made.
Now, from the Phil Jones interview, we have one of the main alarmists actually saying that there is no statistical difference between past rates of increase and current rates of increase. So on that basis claim 1 is false.
So back to your bet. You've said that you think the rates are accelerating. Why aren't you making the bet on that?
What you are betting on is that what must be mainly natural change continuing. ie. You're not making a bet at all on man made versus natural.
Your bet is that over the next X years, there is nothing that will change the natural change.
Now there is another issue, and the skeptics do this just as much as the alarmists and it gets my goat too.
Why are you and others regressing temperature against time? Why are you not regressing temperature against log(co2 concentration)? The claim is C02 is the cause.
You're also at financial risk to another factor. We haven't had a large erruption for a considerable amount of time. That's upped global temperatures. A big erruption over the betting period is more than likely to mean you lose.
Lucia has one of many posts here.
How to test predictions with a confidence measure of how well they do.
By the way, watch for the RealClimate trick on predictions, where they show how well things fit in arrears. Like betting on a horse race when its 90% complete.
You seem contradictory, Nick. It sounds like you think I'll lose my bet, in which case someone really should bet me.ReplyDelete
Lucia has been dismantled multiple times by Tamino. Try this for one:
The conversation's been fun, but it's just you and me, so I'm ready to wrap up. If you think there's room for us to bet, we can talk about it, otherwise you can have the last word.
It's not about the betting. It's about the test that you have to make to show AGW.ReplyDelete
As you've said, its about the acceleration of temperature change over and above any natural change to produce a rate of change that hasn't been seen before, particularly during a time when there is no CO2 increase.
ie. What's the CO2 effect, if any.
However, your bet is that for some reason there is no natural increase in temperature (or decrease for that matter), and the bet is that any change must be anthropogenic.
Hence you're bets don't stack up.
PS, what are you going to do if there is a big volcanic event? From the nature of volcanism, we've had a long gap from a large erruption. Pressure is building
It is about betting, Nick. I feel like you're unclear in your own predictions, but the only thing that matters between two bettors is a divergence in their prediction of the future. If the divergence is big enough, then a bet is possible.ReplyDelete
My bet is about an increase over background, to twice the the 20th Century rate. You may be postulating that somehow will just happen naturally. I don't think that's very logical, but even if it is, it's hardly likely. I think my bet offer should be attractive to someone who has no reason to expect the increase to be likely.
Re volcanism, I don't agree that there's been a long gap, but if it hit at the wrong time, then I could be screwed. In my bet with David Evans, we agreed a large volcanic eruption voids the bet.