Hottest Year

It’s near certain that in the GISS global temperature data set, 2010 will end up the hottest year on record. In fact some of those who deny the reality of global warming have already begun to “spin” the event, downplaying its significance by suggesting that observing the “hottest year” is no big deal. This, from the same people who believe in the mythical “levelling off” or “cooling” of temperatures over the last decade or so.

As I’ve tried to emphasize often, it’s the trend that’s the big deal. Not the moment-to-moment noise, or month-to-month or year-to-year noise, not some false trend you think you see (or don’t see) because you so desperately want to believe in Santa Claus.

Let’s look back at the decade of the 2000s (up to the end of 2009), to discover whether or not it behaved as was expected according to global warming. Then we’ll add the year 2010 to the mix, and ponder whether this single year has any real implication for global warming. To set the stage, here’s the global annual average data from GISS, from 1975 through the end of 1999:

I’ve also plotted the trend line (in blue), which illustrates the global warming trend observed during this time period.

Did that trend continue in the 2000s? In other words, did we observe something reasonably close to the red line in this graph?

The answer is: YES.

Yes, global temperature during the 2000s behaved just as expected, according to the “global warming will continue” theory. In fact the decadal average from 2000.0 to 2010.0 is a wee bit warmer than the projected average using the 1975.0-2000.0 trend.

Let’s add the year 2010 as the final red dot on the graph:

What’s the significance of the 2010 result? Simply that it too is in accord with the “continued global warming” theory. In fact, it looks like the decade of the 2010s is off to an even warmer start than expected.

93 responses to “Hottest Year

  1. Looks like GISS is the outlier, please explain.

    [Response: It’s only an outlier if you’re very dumb.]

  2. I was not referring to the different baselines. The others are going down and only GISS is going up (recently). I am sorry you find such a simple point so difficult to understand.

    [Response: If you were honest enough to look at the data before spewing, you’d notice that of the 4 major records which have reported through December (HadCRU hasn’t yet), 3 of 4 are increasing — GISS is not the only one.

    If you were smart enough to put them on a common baseline, you’d see that there’s no meaningful divergence recently.]

    • Jon P,

      If you look at woodfortree’s notes section you’ll see how to do baseline adjustment and the example given there shows no significant divergence for GISS

      I don’t think anyone finds the point particularly difficult to understand, they simply find it to be wrong.

    • It’s not the only “divergence”, it’s merely the only one that nutty people are assuming is willful fraud. Take a look at Aug-Sep: UAH was going up while the other 3 were either going down or staying about the same. Or look at May-Jun: everyone’s going down but HadCRU. Jun-Jul has everyone going up but GISS. Fraud? In need of some ‘splaining?

      Do they all take turns at have a fraud month?

    • The “sign” of the trend during a particular month makes an appealingly simple indicator of which set is an “outlier,” doesn’t it? Especially when it’s the most recent month.

      Trouble is, if you look through the plot for the year, you can find individual months where each of the four datasets is the “outlier” by this criterion, as well as months where they “split” 2-2, and months where there is “unanimity.”

      But does any of that tell us anything? I don’t see why it would; it’s just statistical noise, I expect.

  3. The first spin I’ve seen comes from a physicist writing for The Oregonian, who claims that this year is as warm or warmer than 1998 because “there’s been a strong El Niño, just like in 1998”. Which, of course, is demonstrably wrong, this El Niño being average, and the La Niña phase quite strong …

    But it plays well with some people, apparently.

      • If you use the Nino indices 2009 was a fairly strong El Nino, but of course the Nino indices are warming because of global warming so they are no longer a particularly good measure of the strength of El Nino. I personally prefer the SOI (or MEI) for this reason.

        Teaching old indices new tricks: A state-space analysis of El Nino
        related climate indices
        GEOPHYSICAL RESEARCH LETTERS, VOL. 32, L07709, doi:10.1029/2005GL022350, 2005

      • Yep, the BOM’s SOI is pretty useful.

        “The current event has contributed to 2010 being Australia’s the third wettest year on record, and Queensland having its wettest December on record.”

        Meanwhile, people I talk to in Indonesia were telling me they completely missed their dry season. It rained right through. It’s a very strong La Nina at the moment.

  4. For people who don’t understand simply trends, it seems like comparisons between decades should be the easiest to understand, as this clearly gets rid of the between year variation. Still, one might hope that a linear trend should be understood by high school graduates.

    • More often than not, the easiest methods to understand are the most logical and in some sense “best”.

      Given that the very definition of climate involves an average of temperatures over some time period (usually 20-30 years, to smooth out the short term “noise” from El Nino, la nina, volcanoes, etc), it makes logical sense that comparing averages (taken over the decided upon period) might be the “best” way to gauge what is happening to the climate.

      If one really understands trends (including the associated uncertainty and the number of years to trend over), one can get similar information to what one gets from comparing averages, but one must have a fairly good knowledge of what the trends mean (and don’t mean) in the given context (in this case climate) to do so.

      Clearly, even some people who use trends frequently don’t really understand them, which is why they are the source of so much unnecessary confusion (and outright deception by those who are smart enough to know better but nonetheless imply that short term trends tell us about climate).

      • Rattus Norvegicus

        You wouldn’t be talking about a certain Anthony Watts, would you?

      • Horatio Algeranon

        The “Dishonest Trend” and the The Stupid Trend” are virtually indistinguishable, but the the noise character[istic]s are very helpful in drawing the distinction.

        The “Dishonest Trend” is characterized by noise with nearly perfect autocorrelation…

  5. Jon,

    Click here:

  6. It seems to me that, at least post-1930, we can see the impact of the solar cycle on global temperature –

    The current warmth is all the more remarkable when you consider that we’re probably at just about the maximum effect of the deepest and longest solar minimum for 100 years. I don’t have sufficient knowledge or skill to properly subtract the ENSO signal, the effects of the PDO, the solar cycle etc., i.e. all of the known natural influences, and just show the anthropogenic influence on global temperature (mainly aerosols and greenhouse gases I presume). Has this been done somewhere? Can you make a reasonable stab at it without a climate model?

    • There’s a nice simple graphical illustration that includes many of the main forcings here:

      References for the estimates of the temperature effect of each of the indices would have been helpful, as would explicit inclusion of the effects of volcanic and other aerosols; but they can be found with a bit of searching (start from the refs in section TS4.2 in the WG1 Technical Summary of IPCC AR4 2007; Hansen et al. 2005, ‘Efficacy of Climate Forcings’, JGR, is an example).

      It is indeed possible to do attribution without climate models. See e.g. Lean & Rind 2008, GRL, and Lockwood 2009, Proc. Roy. Soc. A.

    • I see you added a scale function to make the 2 datasets “work” together. Did you know that you can normalise them instead? This does the scaling for you. I’ve done that here and applied 5-year smoothing to both. I have to say that the influence of the solar cycle looks pretty weak to me.

  7. As far as I’m concerned the US EPA regulations that start today, in that they will encourage mitigation efforts in one of the world’s largest industrial countries, are like the cavalry bugle sounding in the distance at the climax of a Western movie.

    I know this is widely regarded as undemocratic in certain quarters, but my opinion as an outsider to the system is that in the 2007 decision in Massachusetts v. EPA the Supreme Court gave teeth to regulation in the face of the previous administration’s (and consequently the EPA’s) mismanagement. Those teeth are now biting because the legislators as a group didn’t take the problem seriously enough to produce a working legal framework.

    Now the boot is on the other foot. The states can try to challenge the implementation, and Congress can try to amend the law. But the impetus for now is clearly with a regulator that has gone out of its way to follow the spirit and letter of the Clean Air Act.

  8. To me it seems, from the wood for trees graph, that the “odd man out” is HadCRU, being consistently lower than the other datasets.

    The “Arctic hole” in action, I think.

  9. I spent a rainy afternoon last week playing around with some GHCN data…

    Wrote a program to read in the GHCN data sets and compute simple-minded “dumb average” global temperature anomalies (smoothed with a moving-average filter).

    The results were noisier than the official GISS/CRU/etc. results (due to lack of ocean coverage and lack of proper geospatial weighting), but overall results were quite consistent with GISS/CRU/etc.

    Overall summary of the results:

    GHCN raw and adjusted data produced nearly identical temperature trends.

    The 1910-1940 and post-1970 warming periods (which deniers try to claim are equivalent) were markedly different in this aspect: The 1910-1940 monthly *minimum* temperatures showed only a modest warming trend, while the post-1970 minimum temperatures showed dramatic warming.

    The 1940-1970 cooling period was quite evident in the monthly *maximum* temperature data, but almost absent in the monthly *minimum* data.

    So even the most simple-minded data-crunching shows the following:

    1) The individual temperature station adjustments make virtually no difference for global-scale averages. The uncorrected “raw” temperature data generate results nearly identical to the temperature data that deniers claim have been “massaged” to exaggerate warming trends.

    2) The mid-20th-century cooling that shows up strongly in the GHCN monthly maximum data nearly disappears when you crunch the GHCN monthly minimum temperature data. This is quite consistent with aerosol forcing as the probable cause of the mid 20th-century cooling.

    3) The post-1970 warming shows a much stronger greenhouse-gas forcing “signature” than does the earlier 20th-century warming (i.e. a very strong minimum temperature warming trend for the former, and a very weak minimum temperature warming trend for the latter).

    I didn’t accomplish anything new or surprising (or even all that interesting) here, except to show how even the most simple-minded data crunching exercise (something that on-the-ball high-school students could perform) completely debunks all the major WUWT talking-points regarding the surface temperature record.

    Come to think about it, this could be an excellent lesson for college-bound high-schoolers. With a bit of guidance, high-school students could perform a more thorough analysis of the GHCN surface temperature record in a few days than the WUWT crowd has managed to do in nearly four years!

  10. Since 2010 seems to be a new upper outlier in the trend, it will be a great candidate to be a sequel to the “no warming since 1998” series:

    “It hasn’t warmed since 2010”
    “Ok, 2020 was really warm but we’re sure this time it will start to cool…”
    “Wait, 2049 turned out to be slightly cooler than 2045, so global warming stopped again!”
    “2100: the trend has been upwards for two or three centuries, but it stopped so many times that we’re sure it must count as a cooling trend…”

    • Outlier? I don’t think so.

      Looking at the graph Linear+/-2SD from You Bet!, 2010 is only about 1 standard deviation from the linear trend. 1998 was nearly 2 standard deviations.

      The NASA GISS rolling 12-month global average is currently 65.17. 2005 is easily statistically tied at 62.58. The difference is less than 3/100 °C. It is statistically tied up to 5/100s. In contrast the anomaly for 1998 was 56.50. The highest annual anomaly before that was 39.33 set in 1997. That is a difference of more than 17/100s.

      For the rolling averages please see:

      • Ok, ok, I’ve been busted. I just eyeballed the graph and called the dot clearly above the trend line “outlier”. No idea how to calculate standard deviation…

        Man, it’s hard to be a layman in these blogs!

        (just kidding. Thanks for the attempt to teach me something…)

    • The ‘no warming since 2010’ has already started. On January 30 the temperature turned downwards at AMSU, channel 5 @ 14,000ft.

    • You know, I hate the term “outlier”. All too often it is merely a convenient way to dismiss a datapoint that doesn’t fit the model. Much more often, it is a rare gift–an insight into the behavior of the tails of the distribution. By definition, data from the tails is a rarity. It carries critical information. It should not be dismissed.

      As to 2010, it doesn’t come close to being an outlier, probably well under 1.5 sigma off the trend, and probably less of an outlier than 2005.

      • The Liar and the Outlier
        — by Horatio Algeranon

        Said the Liar to the Outlier:
        “You simply can’t be real”
        You do not fit my desire
        Which has great sex appeal”

        The Outlier to the Liar:
        “I represent a truth”
        “Don’t use a gun for hire”
        To carry out your proof”

        The Liar to the Outlier:
        “Shut up and prepare to die”
        “When I throw you on the pyre”
        No one will ask ‘Why?’ “

  11. caerbannog:
    Your any idiot can do it assertaion insults twp of our loudest Canadian climate bloggsters and will not be tolerated by us real canuks eh!

  12. caerbannog:
    Your any idiot can do it assertaion…

    Hey! I resemble that remark. I was able to do it, and I’m not an idiot (I think).

    Besides, if any idiot could do it, one of the WUWT idiots would have certainly done so by now!

  13. This blog claims to use November HadCRUT data:

    Is that the November data (click on HadCRUT,) or is their release likely to be a different number?

    Just curious, what takes them so long?

  14. Alexandre,

    I liked your sequence. One thing, though–there probably won’t still be working printing presses or blogs in 2100.

  15. On HadCRUT, this news from the UK’s Met Office may be of interest:

  16. arch stanton

    1- Although 2010 started out as a moderate El Nino, it changed to a La Nina. Predicted influence compared to strong El Nino in 1998: Cooling. Observation: No significant cooling.

    2. Unusually long inactive period of sunspot activity. Predicted effect since 1998 according to the GCR and other “it’s the sun” theories: Cooling. Observation: No significant cooling.

    3. PDO in its “negative” phase. Predicted effect on global temperatures since 1998: Cooling. Observation: No significant cooling.

    Today the folks @ Watts’ are cheering on a conspiracy theory post by a Dr Maue who doesn’t even know that temperature change percentage is calculated in K.

  17. Steven Leibo

    Basic question, how soon will we know for sure that 2010 was the hottest year?

  18. Tony Sideway stated “I know this is widely regarded as undemocratic in certain quarters,…”

    The 1990 Clean Air Act specifically states that one of its goals is to reduce anthropogenic global warming. It’s a “big lie” mouthed by FOX news and similar mouths that the U.S. Supreme Court engaged in judicial activism. As if this Court would do so on the behalf of the environment is absurd. The Court had no choice as the law is clearly written to include greenhouse gases. All the Court had to decide was whether or not carbon dioxide was a greenhouse gas. If so, then it is subject to regulation under the 1990 Clean Air Act. From the Senate version, Title V:

    SEC. 502. (a) The objectives of this title are to restore and maintain the chemical and physical integrity of the Earth’s atmosphere, to protect human health and the global environment from all known and potential dangers due to atmospheric or climatic modification, including stratospheric ozone depletion, to provide for a smooth transition from the use of ozone-depleting chemicals to the use of safe chemicals, products, and technologies that do not threaten the ozone layer, and to reduce the generation of greenhouse gases in order to protect the Earth’s ozone layer and to limit anthropogenically induced global climate changes by–

    • Surely the Republican House isn’t going to allow this EPA initiative to survive! If the can swing a few Senate Blue Dog Dems or attach it to some veto-proof bill… They will do everything humanly possible to stop the EPA regulating CO2 emissions.

      • Their options are limited …

        Let them attack the Clean Air Act directly, and let Obama get on national TV, talking about all the benefits that have accrued under this act – signed by a Republican President and supported by a large number of Republican Senators and House members – and making it clear that they’re trying to roll back to the days when polluters poured whatever they wanted into the air without fear of government action.

        Obama (and other leading democrats) need to attack in public, pounding home the point that Republicans want to put air quality back into the hands of unregulated industry.

        There’s widespread support for air and water quality laws. Obama and the dems can tap into this.

      • The Repubs will try and defund implementation of GHG regulations. To clarify, the version of the federal budget that passes the House will prohibit spending on GHG regs, while the version that passes the Senate will allow it.

        Dems will have to choose between compromise or a stare-down that could shut the government. Very similar issue to health care, and it’s going to be tricky. I think there may be a trade-off: Dems get to implement health care, and GHG regulations get suspended for one year, with the same thing happening again next year. Not good.

      • I don’t think the Republicans will want to replay the shutdown scenario they forced during Clinton’s administration. They got their lunch ate on that one.

        One question I have, though … when do they decide to try to impeach Obama? Do they wait for his second term, as they did with Clinton? Or did the boost their impeachment efforts gave to Clinton’s popularity make it unlikely they’ll try the same tactic with Obama?

      • Dhogaza,
        I don’t think the Republicans will try to impeach Obama. They like their chances in 2012. All they will try to do is make it impossible for him to accomplish ANYTHING, no matter how much it hurts the country. In the end, their hatred of liberals trumps love of country.

      • The Tea Party and the Republican Guard may be at war by February.

      • Ray, he’ll win in 2012. They’re dreaming.

        I tend to agree that they’ll reserve their most desperate step until afterwards …

        Just as they did with Clinton.

        (remember, the Republicans were *sure* they’d unseat him in his re-election attempt, the first after election Rush broadcast was precious, I tuned in and loved every minute.)

      • In the end, their hatred of liberals trumps love of country.

        Sure, they’ve even said so …

      • Dhogaza, I think you underestimate the level of racism in this country.

      • Hope this threads right–I’m responding to Ray but have miscalculated threading a couple of times lately. Anyway, it occurs to me that if “hypocrisy is the tribute vice pays to virtue,” and Ray is right in his suspicion that there is a component of racial bias in opposition to the President–and he’s not the only person I know who suspects this–then it’s encouraging in a way that this opposition needs the cover of policy disagreement (albeit frequently highly specious policy disagreement.)

        In short, if racist are ashamed, well, so they should be. But I suppose I’m way OT, for the second time this morning.

        [Response: Yes, way OT.]

  19. David B. Benson

    So far my prediction for the average GISS global temperature for the decade of the 2010s is on track:
    Only 9 more years to go.

  20. 2010 is a major breach in the dike for the WUWT world, and Watts is hurling whatever sandbag he can find into the hole.

    This post, not surprisingly, is all bag and no sand.

    • The conflation and disingenuity in that opening para over at aW’s beggars belief.

      Note the “1934 has long been considered the warmest year of the past century.” opening, with the implication seemingly/clearly being “global” following on from the title of the piece: “2010 – where does it fit in the warmest year list?”

      And then the “Since then, NASA GISS has “adjusted” the U.S. data for 1934 downward and 1998 upward…” a couple of sentences later.

      Well, last time I looked 1998 was classified as second (or equal first within error) to 1934 in terms of US warmest years.

      Oh, and 1934 ranks as 40-somethingth in the list of global warmest years.

      That scraped barrel must be no more than an atom or two thick by now.

    • Not to worry, I’d be happy to give MicroWatts all the sand he can pound.

  21. The 1934 canard really stands out. I’ve encountered it a lot in discussion threads, and when I do I know while there’s no hope of getting through to the person who raised it, at least it’s going to be easy to demonstrate to others that here is somebody who doesn’t know what he’s talking about.

    • Rattus Norvegicus

      Yeah, this one comes from McIntyre. Before the 2007 correction for USHCN v1 vs. USHCN v2 1934 was in a statistical tie with 1998 as the warmest year in the US. After the correction 1934 was in a statistical tie with 1998. Fraud! Subterfuge! But wait, nothing changed in the global average…

    • Hey, don’t forget that this piece contains a really outstanding piece of writing–the immortal phrase, “global temperatures in the Northern hemisphere.”

      But you must excuse me; I’ve a full-body ache in my head.

  22. Not sure if it offers any comfort, but 1934 is used by high profile deniers in newspaper op-eds, etc over here in Europe as well.

    Will be interesting to see the UAH data. for 2010. According to the website, channel 4 has been down with “Channel data problems beginning mid Dec 2010”

    • I’d noticed that the anomaly just suddenly “fell off a cliff” there. I guess we have to stay tuned.

      I also seem to recall that Tamino has been very suspicious of the AMSU numbers throughout the year. (A clear example, BTW, of NOT falling victim to confirmation bias, since they’d been running very warm all year.)

  23. Marion Delgado

    BPL: That makes me want to live till 2100 just to see the last of ClimateAudit and WattsUpWithThat. And Regnery.

    • Unfortunately, I suspect that the Denialists will still be holding their annual conference in the tropical coastal resort of Aspen, Colarado to claim that it is completely normal and in any case people can just adapt by going about their business in scuba gear, and who really needs to eat, anyway?

  24. Regarding the new baseperiod for UAH. My theori is that Spencer / UAH get panicked when Decembers 2010 came in higher than december 1998 that he had to fix it right away so that not 2010 would be the warmest year. Therefore, he decided to quickly change the base period. What do you think? Does anyone know if you can find out what Spencer’s figure for December was with the old base period?

    [Response: If 2010 had been the warmest year, changing the baseline wouldn’t change that. I don’t think there’s any nefarious purpose to the change in baseline.]

    • Have you considered that maybe he just wanted to mess with Watts’ head? If I had a fanboy as dumb as Watts, I’d want to mess with his head, too.

    • The UAH change coincides with the new WMO normal period 1981-2010. Previously, the time series didn’t have enough data to cover a traditional normal period.

    • The change to a 30 year base period at the end of the decade (December 31, 2010) is a good move and totally consistent with good climate science practice. I think all the temperature records should be set versus the same baseline to avoid the kind of mistakes made repeatedly by Watts and the deniers when they compare global anomalies without correcting for the baseline.

      But I doubt that Spencer is as innocent as some suspect in setting up and providing fodder to Watts. Spencer essentially set Watts up as an outside channel to attack other climate scientists. In case you missed the distinction, I said “attack climate scientists” instead of “attack climate science”. The general public thinks in terms of good guys and bad guys, and there was a strong need among deniers to destroy the favorable image the public used to have of scientists, particularly NASA scientists. Establishing and supporting WUWT is part of a propaganda war.

  25. Marion Delgado
    BPL: That makes me want to live till 2100 just to see the last of ClimateAudit and WattsUpWithThat. And Regnery.

    But, seriously, don’t you want to, anyway? I’d love to see how this all turns out, but I’ll be long gone by 2050. I admit to a wistful sense of missing out on the big news.

    • Adam, I’m afraid my gut feeling is that you’ll get to see some pretty significant developments long before 2050. I’d give pretty long odds, for instance, that Arctic sea ice will become a seasonal phenomenon before that–maybe quite a bit before that.

      • Adam, I’m afraid my gut feeling is that you’ll get to see some pretty significant developments long before 2050. I’d give pretty long odds, for instance, that Arctic sea ice will become a seasonal phenomenon before that–maybe quite a bit before that.

        Oh, I don’t doubt that, but I would really like to know what the global average temperature divergence will actually be by 2100, and what the state of the Greenland and W. Antarctic ice sheets will be by then.

      • Agreed! The odds of me being around in 2100 are microscopic–negative impacts on human civilization aside, medical technology would have to go an awfully long way, and I’d have to be able to afford the best!

  26. I don’t think there’s any nefarious purpose to the change in baseline.

    I think there is, and I think it is entirely due to pawning towards the denialsphere, who seem to think that the baseline is all-important.

    Certainly Spencer’s buddy Watts continuously asserts it is. Spencer changing his puts Watts in the position of saying, “hey! honest scientist Spencer agrees with me, and has changed his baseline!!!!”

    Meanwhile, Spencer’s off the hook with the scientific community presumably that since there’s now 30 years of data to form a baseline, it makes sense to do that (it does).

    But if you have any faith that Spencer will stand up to these people (who he explicitly supports), nah, not at all.

    Clever move on Spencer’s part.

    Just before the witch hunt begins in the House.

    • Funny, I was just trying to explain yesterday that the fact that warming early in the UAH record is not negated by the fact that temps then mostly fall below the baseline. (The argument, if you can call it that, is that it’s not warming, just a “return to normal.”)

      It’s hard for me to imagine Dr. Spencer either anticipated or intended to encourage such a wacky idea, but clearly the longer baseline “eliminates” more warming for the deluded gentleman with whom I was interacting.

  27. Halldór Björnsson

    Thank you for a very interesting post. These figures are amazing. When trying to estimate the forced trend in global SAT the natural variability means that 10 year trends can have a fairly large scatter (as has been discussed in this fora and others). It is therefore intriguing to see that this decade has a trend that so well matches the 1975-2000 trend. How does this look in CRU and NCDC ?

  28. > not negated by the fact that temps then
    > mostly fall below the baseline.

    Those susceptible to this kind of deception likely believe that by raising their own beltlines higher and higher, they somehow hide their pot bellies.

  29. Hank Roberts,
    Ooh! And don’t forget combovers! I’ve seen some beauts! One guy had his combover slicked down and a single strand of hair wound round in a spiral.

    Best one though was a Russian cosmonaut on the International Space Station. I will leave it to the imagination of the reader to give you the picture of what a combover would look like in space. In space, no one can hear you snicker.

    • Love the comic relief. I suppose it’s technically OT on “hottest year,” unless you count how the juxtaposition of the mental cosmonaut picture with the word “hottest” provides a nice little irony.

      Of course, my hair isn’t a “combover”–just the result of combining constant hairstyle with, umm, historical trends. Hmm–wonder if there’s a correlation with SIE? With proper definitional choices, that would give a whole new meaning to “we are the world.”

    • Cosmonaut? Sounds like time for some hair gel. But he would want to be careful with the tube — otherwise things could get really ugly, real fast.

  30. Steve Metzler

    I was trying to figure out where Tamino got his GISS data from, because the anomalies I had seen were greater in magnitude than what he has plotted:

    But then I finally realised that I was looking at the land only anomalies, whereas Tamino is using the land-ocean combined data:

    No bonus points for figuring out which GISS data set Mr. Watts prefers, and for what reason. Still, 2010 has already kicked every other year into touch according to either data set, including 1998 and 2005. No doubt the inimitable Mr. Watts will find some way to discount this result.

    As others have pointed out, Watts’ favourite data set is HadCRU, which has poor arctic coverage… where a significant amount of the warming is happening.

  31. Steve: I have also noticed that the deniers quote the CRU data a lot lately.
    Wasn’t that the dataset that the deniers proudly proved fraudulent in that Climategate thing? Seems odd to use that dataset now, considering that it is proven fraudulent and all.
    I wonder why…

    • Compartmentalization is a classic denialist trait. So the CRU dataset is fraudulent, unless it can be (mis)used for a specific purpose, in which case it becomes the most accurate.

      In a similar manner, Climate Sensitivity is extremely low when driven by carbon dioxide, but extremely high when driven by the sun. And anyone suggesting a contradiction is clearly part of the great Conspiracy.

  32. Some amateurish futzing around with Woodfortrees yields:


    At face value, it appears there is some leveling off at high temperatures – could be a lie, damn lie or statistic, I’ll grant you.

    [Response: Since by your own admission it’s “amateurish” and you don’t know whether it’s meaningful or not, why did you post this?

    Could it be that you’re trying to imply something? Could it be that if your implication is subjected to rigorous statistics it fails utterly, so you had to couch it in “amateurish fooling around” terms?

    ‘Cause if your implication is subjected to rigorous statistics, it fails utterly.]

  33. Wow, I was not expecting that at all! But on reflection I can see it was badly worded, so mea culpa. I’m not a statistician at all, just trying out the Woodfrtrees site introduced here and exploring the topic. I was assuming you would point out what’s wrong with using an uneducated 10, 20, 30 year approach (“face value”), but it’s a touchy subject, I see. As the late Gilda Radner used to say, “Never mind!”

    [Response: That’s something I’ve pointed out before. Many times. I’ve done it again and again and again and again and again and again … so many times, that if you read this blog on a regular basis you can’t possibly have missed it.

    And if you don’t read this blog, then why post your speculation here? I’m still favoring the “you have an agenda and wanted to make an implication” theory.]

  34. Tamino, I’ve used your graphs in one forum response in one Slovenian magazine, trying to spread some really quality data. Source is here (mostly is in Slovenian,, article talks about global warming fraud and I could not help myself to put serial objections about false claims). Of course, I’ve referenced your blog as a source and linked all original text , so I hope you don’t mind I’ve did it this way. I’ve used your graphs as an example, how trends from 1975-2000 should be extended and how GISS temp has been just right on trend. Of course, if you have some objections, I will remove the links and data.
    Anyway, thank you for your good work.
    I have a small question, if you can help me. The guy referenced some warm periods prior to 1 AD, mostly 5000 years BC (I am really F grade here). I remember you had a post about Arctic ice, from which, if I understood you correctly, this period was really warm. Do you maybe know (I might be a little bit lazy here not surfing and trying to really find relevant sources here) about documents and if applicable, some good comments about those periods.
    And yes, I am really waiting for your new posts, as I percieve them as state of the “art” – the way I think things should be analyzed and presented. So many, many thanks again and thumbs up :)

  35. Sure as heck are the Aussies experiencing the extremes… drought on the west and drowning in the east. Looked at the SOI index and it does seem like December showing an extreme positive value (highest I recollect). Pielke would claim all that heat had dissipated to space, he did early in this La Nina phase, but a simple animation showed recently that the southern trade winds had effectively pushed allot of the hot Pacific surface water up the Australian coast and massive evaporation being the source of the torrential rains there in Queensland.