Home > CRUTEMP, GIStemp, satellites > Did Global Warming Stop After 1998?

Did Global Warming Stop After 1998?

2010 December 31

Tamino had an interesting post in Jan 2008, nearly three years ago, which I will refer to as Tamino’s Bet. It displayed one way to test if a trend has continued, stalled, or reversed. No doubt that it is not the most rigorous statistical treatment around – maybe not even close. But it sure is visual.

Here is Tamino’s original chart. You can find the companion text via Skeptical Science’s archive of old Tamino posts.
Tamino's Bet

I’ve slightly altered Tamino’s original format – As I recall (3 years ago), he used an average trend for the 2001-2007 to set the horizontal ‘no trend’ bars. The charts which follow just extend the trendlines horizontally from the last date in the data used to set the trend. And the trend in his original post used data through 2007. This post only uses the data to 1998 to set the trend.

I used the data set prepared by O’Day over at Climate Charts & Graphs (O’Day). Thus, we have charts for GISTEMP, HadCRU, NOAA, UAH, and RSS. The data for Dec 2010 is still missing – but I’m using the ave for Jan-Nov for the 2010 annual data.

The script is here

Trend GISTEMP 1998 30

Trend CRU 1998 30

Trend NOAA 1998 30

Satellite data does not extend far enough back to run 30 year trends. These are 18 year trends.

Trend RSS 1998 18

Trend UAH 1998 18

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  1. Kelly
    2010 December 31 at 8:52 am

    Ron

    Very nice job! Glad to see you are using my data set.

    Kelly

  2. 2010 December 31 at 4:00 pm

    Thanks for putting it out there! I’ve often skipped over to your site to learn an R trick or two and greatly appreciate your work.

  3. 2011 January 2 at 1:52 pm

    I’ve been watching this since my readers alerted me to it. (Of course it’s not a real bet because no one actually bet. Plus, Tamino said he didn’t plan to bet real money. But, still, people are still comparing data to that “bet”. :) )

    I’m pretty sure I told someone that the reason I didn’t think the bet was very useful for “proving” anything was that it would likely to take way too long for anything to happen. Also, if it is warming, but at a rate noticeably lower than suggested by the years Tamino picked to create the bet (which was 0.018173 C/year, computed from a fit to were from 1975-2007 for GISSTemp), there was a pretty good chance the person betting “no warming” might win despite the fact that warming is happening. (For example: Imagine if “true” warming is 0.15 C/year. Then, depending on the timing of El Ninos and La Ninas, we might get two years below that lower red line exceeding the upper blue line in Taminos figure. Then, “no warmers” win. Meaning… what? )

    One interesting (to me) thing is that we remain in a situation where none of the years fall in the region to accumulate even one year required to meet the “two-years” criterion. The two La Nina years were not low enough to give someone who bet “no warming” a year in their pocket; this year is not high enough to give someone who bet “warming” a year in their pocket. Had anyone actually bet, no one would win until at least year end 2012.

    Oddly enough, the way the original bet was set up, it’s hypothetically possible that the bet will eventually be a draw. Imagine if it’s not won before 2027 and we’ve had 1 year below the 0.735C for “no warming” to lose but also had one year above the line required for “still warming” to lose. Then the temperature in 2027 comes in at 0.736C. That’s above the level required for “no warming” to lose but below the level for “still warming” to lose. So, according to the rules, that year both no warming and still warming lose! Does the money that was never bet go to charity? (Or do we just add it to my trove of quatloos?)

    I don’t expect that odd situation to occur– but it could!

  4. Kevin Stanley
    2011 January 3 at 10:09 am

    @ lucia, re: “I’m pretty sure I told someone that the reason I didn’t think the bet was very useful for “proving” anything was that it would likely to take way too long for anything to happen.”

    and: “One interesting (to me) thing is that we remain in a situation where none of the years fall in the region to accumulate even one year required to meet the “two-years” criterion. The two La Nina years were not low enough to give someone who bet “no warming” a year in their pocket; this year is not high enough to give someone who bet “warming” a year in their pocket. Had anyone actually bet, no one would win until at least year end 2012.”

    I don’t think you should be surprised–things seem to be going at pretty much the pace Tamino anticipated. He was eyeing mid-decade for a likely resolution, as he wrote in the original post: “By the end of 2015, it is in fact likely but by no means certain that one or the other side will have won.” And he observed that “although it’s unlikely, it’s possible that this bet could be undecided until the end of 2028.”

  5. 2011 January 3 at 11:00 am

    Kevin–
    My comment about the bet not being useful for ‘proving’ anything was based on a recollection of a conversation with someone at my blog. The fact that the method is very slow, not real bet and risky makes it not as splendid as the advocate suggested.

    Also, interested is not a synonymn for “surprised”. :)

    But maybe I should elaborate. I’m sort of expecting this won’t be resolved by 2015. Recollect that a 1-0 score would also leave no winner or loser. For now we have a 0-0 tie. That makes the 2012 currently the absolute minimum first date for resolution of “the bet”.

    It looks like next year is a La Nina. I don’t anticipate La Nina being deep enough to give the coolers a “1” in their favor this year, but it’s highly unlikely to give the warmers a 1 in their favor. I suspect the outcome at the end of 2011 will still be 0-0. If that happens, then 2013 would become the first possible date for resolution of the bet.

    But if the current La Nina turns particularly severe, it could be 1-0 in favor of the coolers. A Pinatubo volcanic eruption early enough in the year could tip this further in their favor. (In fact, upcoming La Nina combined with the possibility of volcanic eruptions means that a 2012 resolution — should it occur– is more likely in favor or coolers!)

    What’s unlikely at the end of 2011 is 0-1 in favor of warmers. I’m not going to say it can’t happen– maybe it can. But I doubt it will.

    To resolve by 2015, what needs to happen? Given the ENSO cycle, if the underlying warming trend is as stated by Tamino in his bet, the warmers need 2 El Ninos to get their 2 points anytime soon. Admittedly, we have 2012, 2013, 2014 and 2015 to permit these El Ninos. But still, there is a pretty good chance that the warmers cannot achieve the required 2 El Ninos — with little volcanic interference– by 2015. Could they? Sure. Is it 50/50? Depends on your guess on the likelyhood of volcanic eruptions.

    So, it seems to me this exercise was very slow and a bit risky.

    And who, precisely is it organized to “prove” anything too? If Tamino loses the bet because 2011 turns out to be the La Nina of the Baskervilles, and it’s followed by a year with two volcanic eruptions, I’ll still believe in global warming. But of course, the graph will be shown. Heck, I’ll show it. (I’ll show it anyway. Since Ron blogged, I’ll blog this when the Dec. GISTemp comes out.)

    And he observed that “although it’s unlikely, it’s possible that this bet could be undecided until the end of 2028.”

    I think, as worded, the bet could continue to be disputed even after 2028.

    How do you decide who wins if the temperature is in both the pink region and blue region at the same time? If someone has bet they almost certainly would have insisted the rule for that be stated explicitly. I’m under the impression that in contracts, anything vague is read in favor of the person who did not write the contract. So, presumably, the “no” warmers win if, after 2028 the temperature is below the lower red inclined line but above the upper blue line. Right? Or would those who wagered on the warming side of the bet want the vagueness to be interpreted in favor of the person who wrote the vague rules? So, unless the person who wrote the rule concedes vagueness in favor of his own position losing, the bet could be disputed forever.

    Thinking of this, I might have to try to estimate the probability of warmers losing. (I think they still have the edge– but they need to survive the upcoming La Nina and ill timed volcanic eruptions. If they do, then I suspect the probabilities tip wildly in the warmer’s favor.)

  6. Kevin Stanley
    2011 January 6 at 9:03 am

    Lucia, your anticipations seem to make sense given most of the historical impacts of ENSO, and if you’re right about La Nina dominating the coming year. I think it’s interesting (and surprising) that the GISS anomaly for November was .74 (a year of that, and that’s one in the warmer’s column) while in the midst of the La Nina that began in July. I suppose we’ll see December’s anomaly in the next few days. It seems unlikely that it will also be so high (but then it also seemed unlikely that November’s could be so high). FWIW Climate Prediction Center is forecasting a reduction in the intensity of the La Nina conditions into the Spring, and questioning whether they will still be around in the Summer.

    As for the utility of Tamino’s approach, and your question “And who, precisely is it organized to “prove” anything too?” I think that it stands as an exercise in how one evaluates evidence. That seems sorely needed to me, as I watch people around me become swayed on issues of science by emotional appeals to their political predilections and/or intuitive sense of how things should work (in areas in which they have no expertise). Put bluntly, it seems to me that the average layman, here in the US at least, is *terrible* at weighing evidence. Tamino’s bet, imperfect though it is, shows how one might sensibly do that in the case of global warming. And among other things, it inspired this edifying series by Ron :)

    When you get into looking at it as the basis for a formal bet, i.e. a contract–well, your points seem valid to me but inconsequential, since the value I perceive is in deepening the reader’s comprehension of the science of global warming, and not in making a water-tight legally binding contract that dictates who ends up with what money based on which contingencies. I think about the issue of “proving” something to someone in a similar way. Tamino’s bet helps clarify some of the evidence (global temp records, GISS in particular) and provides a framework for evaluating the new evidence as it comes in. This strikes me as important and useful. On the other hand being able to…how do I say this…perhaps “win a syllogism contest”–to be able to claim you have “proved” something–seems more like sport. Entertaining, but ultimately less important.

    Perhaps it’s unnecessary to say this, but that is of course just *my* opinion of the value of the approach. I don’t know any more about whether Tamino feels it is meant to “prove” something to someone, or how he feels about its value as the basis for a binding wager, than does anyone else who reads the post.

    I’ve perhaps gone on too long already, but maybe the perspective I’m trying to present can be illustrated with issue of the post-2028 zone of possible temps that neither warmers nor coolers could claim. If you’re looking at it as an issue of how a contract would be treated, this is a big problem. If you’re looking at it as a lens for examining evidence, it allows you to see–in pleasantly digestible graphical form–that values in that range would provide strong evidence that warming is proceeding, but that the rate of warming has reduced relative to the reference period. Obvious from your current state of knowledge, perhaps, but imagine if you just asked a layman ” what would global temperature anomalies of +.77 in 2028 and +.75 in 2029 tell you about global warming?”

    Understanding the significance of that data for the Earth’s climate seems important to me. Understanding the significance of that data from the perspective of a casino hosting a wager seems interesting, but not important.

  7. 2011 January 6 at 10:13 am

    Kevin

    while in the midst of the La Nina that began in July.

    We’re getting a lot of spin on both sides about whether this is a “La Nina” or “El Nino” year. Given the observed lag between ENSO and GMST, I think most would conclude 2010 was dominated by El Nino. It wasn’t a particularly strong El Nino, but it was El Nino. So, I’m not surprised 2010 was warm. I was expecting some records to be broken.

    It seems unlikely that it will also be so high (but then it also seemed unlikely that November’s could be so high).

    I’ll be surprised if Decembers HadCRUT, NOAA or GISS are high. But then I was surprised Novembers were high. :)

    FWIW Climate Prediction Center is forecasting a reduction in the intensity of the La Nina conditions into the Spring, and questioning whether they will still be around in the Summer.

    The NOAA monthly discussion came out this morning. It reads:

    The current ENSO model forecasts have not changed significantly compared to last month (Fig. 6). La Niña is currently near its peak and is expected to persist into the Northern Hemisphere spring 2011 at a lesser intensity. Thereafter, there remains considerable uncertainty as to whether La Niña will last into the Northern Hemisphere summer (as suggested by the NCEP CFS and a few other models), or whether there will be a transition to ENSO-neutral conditions (as suggested by the CPC CON and a majority of the other models).

    Nevertheless, what we know is entering the year, we are in a La Nina. Global temperature lag. So, likely, the effect of La Nina is likely to last through the end of summer– or later. (Ron did a fit of surface temperatures to NOAA and find the best correlation indicates a 6 month lag. I’d done something guessing a 2 month lag. If La Nina lingers until early spring, La Nina’s influence ought to be to keep temperatures down for at least 1/2 the year and possibly 3/4 of the year.

    I think that it stands as an exercise in how one evaluates evidence. That seems sorely needed to me,

    I agree that methods to evaluate evidence are sorely needed. I agree that Tamino’s method might be somewhat useful for evaluating evidence for something. But it’s generally better to evaluate a specific persons claim against another specific person’s claim. My question is goes to this: Evidence for what or whose question or claim?

    I don’t think there are many people out there who claim the earth is actually cooling. In principle, Tamino’s bet tests this groups notions– but they pretty much don’t exist. So, weighing evidence of something almost no one claims against something someone claims is a bit odd. So, if he was arguing with someone in particular he should have named and quoted. Otherwise, when the issue is “resolved”, it will appear to those he might think he is trying to convince that he set up a bet to engage a strawman. (That is: an argument not advanced by anyone.)

    Whether or not the method of presenting evidence shows that a strawman has been vanquished, that exercise is never “useful”. The reason is it shows the evidence indicates something no one ever believed is false. (Yawn.)

    I know a few who at least seem to think there is absolutely no warming even in the long term. Not very many, but a few. This is the only group of people whose notions are tested relative to Tamino’s. But once again: If the exercise is to convince this group, he should have named and quoted who they were. Then, they could step forward and clarify if he is interpreting their view correctly.

    A larger number of people think there is long term warming, but underlying warming is not as fast as claimed. Some of these think warming is so slow there might be short term — i.e. two decade long cooling owing to the AMO, but they aren’t necessarily firm on that. Tamino’s bet is utterly useless for this issue because they believe in so much variability that they will continue to believe what they believe no matter what the outcome of that test. So the test does not engage anyone in this group.

    I know others who don’t even believe global temperatures “mean anything.” Example– Andrew_KY. Also, no matter what the outcome, Andrew_KY is going to just respond that these are squiggly lines. Some other commenters are going to reply that you can’t define global temperature etc. Tamino’s test will never engage someone like Andrew_KY.

    So, who will this exercise convince?

    since the value I perceive is in deepening the reader’s comprehension of the science of global warming,

    Except I don’t see the bet as having much value this way. It’s not useless. It’s not tremendously useful. But yes, it’s a way to discuss things, and I too will be discussing it. In January. :)

    If you’re looking at it as a lens for examining evidence, it allows you to see–in pleasantly digestible graphical form–that values in that range would provide strong evidence that warming is proceeding, but that the rate of warming has reduced relative to the reference period.

    Well… or the underlying trend never was 0.18 C/decade, and that particular value frozen into the bet was on the high side achieved as a result of “weather noise”.

    But the fact is, once 2028 arrives, we don’t need “the bet” for that. You can just look at trends.

    Understanding the significance of that data for the Earth’s climate seems important to me. Understanding the significance of that data from the perspective of a casino hosting a wager seems interesting, but not important.

    Well… sure. But Tamino’s method sets it up as a Casino wager. It’s when people suggest the Casino wager is somehow more convincing or better, or clearer that I demur. It’s not. It’s a method. It has some utility. But loads? More than other methods? Not really.

    It’s an interesting idea. And…as Anthony Watts once said to me, you gotta feed the blog. So, in all, the wager is a fun thing. I’ll blog it. Ron will blog it. People will.

    Those who believe in warming should cross their fingers and hope that we don’t have two major volcanic eruptions in the in the next two years though. If we do, the coolers may well win that bet. Then it won’t be such a terrific teaching tool. (If warming doesn’t lose the bet by 2013, I think the odds shift stupendously in terms of warming winning or no one winning.)

  8. 2011 January 6 at 2:16 pm

    “Gotta feed the blog”

    I can say, looking back after my first year, that is true – but you also have to be careful not to let the blog feed on you. :D

    A note to readers – I discovered that I had reversed the indices for UAH and RSS. The appropriate data and those labels are switched in these satellite graphs. I will be updating the graphs shortly.

  9. 2011 January 6 at 2:25 pm

    Ron–

    you also have to be careful not to let the blog feed on you. :D

    Absolutely! :)

    Anthony’s point is, of course, that maintaining readership does require a blogger provide new content at regular intervals. My impression is that part of the reason he has several guest or co-bloggers is to keep the stuff “top of the fold” fresh.

    My UAH bets are regular and bring in visitors out of proportion to the significance of the monthly temperature outcome. They aren’t very time consuming either.

  1. 2011 January 14 at 4:00 pm
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