Satellite Measurements

Spencer and Christy have amended their satellite algorithm. Here are some links and comments, courtesy of ukweatherworld. I anticipate that there will some huffing and puffing about this, but Hans Erren’s graph should keep matters in perspective.

The ukweatherworld discussion is here.

The updated satellite data is here with the following comment:

Update 7 Aug 2005 ****************************
An artifact of the diurnal correction applied to LT has been discovered by Carl Mears and Frank Wentz (Remote Sensing Systems). This artifact contributed an error term in certain types of diurnal cycles, most noteably in the tropics.

We have applied a new diurnal correction based on 3 AMSU instruments and call the dataset v5.2. This artifact does not appear in MT or LS. The new global trend from Dec 1978 to July 2005 is +0.123 C/decade, or +0.035 C/decade warmer than v5.1. This particular error is within the published margin of error for LT of +/- 0.05 C/decade (Christy et al. 2003).

We thank Carl and Frank for digging into our procedure and discovering this error. All radiosonde comparisons have been rerun and the agreement is still exceptionally good. There was virtually no impact of this error outside of the tropics.

Hans Erren posted up the following graphic at ukWeatherworld and his website to show the effect (Hans helpfully included the R-script)

One of the ukWeatherworld posters said: "The global decadal trend is now 0.123 K – similar to the surface data." I don’t think that this is the case at all. I’m not sure that statistically it makes a whole lot of sense to talk about "trends" to 3 significant digits in data with as much serial autocorrelation as this, but, leaving that aside, the difference between the Jones data and the satellite data (even after this adjustment) is much larger.

I haven’t updated the figure calculated last April and re-posted here, but you get an idea of the difference beween the satellite and Jones data. There is a big knock-on effect in this difference, because it is the difference that levers the detection-attribution studies.

Figure: See here

36 Comments

  1. Reid B
    Posted Aug 9, 2005 at 6:58 PM | Permalink

    “We thank Carl and Frank for digging into our procedure and discovering this error.”

    Spencer & Christy have treated Carl Mears and Frank Wentz they way Mann should have treated M&M.

  2. John Cross
    Posted Aug 9, 2005 at 7:46 PM | Permalink

    In fact Steve, that is about a 40% increase. I guess I am one of the huffers and puffers since I will point out that the old data set has been a staple of a lot of papers and publications from Soon’s early OISM petition project, through landuse change effect studies (i.e. Kalnay), statistical studies like Karner’s and of course the three “Bombshell” papers presented last year. There will be a lot of ramifications that will fall out of this work.

    Reid B – Humm, I think a better analogy would be how S&C treated Fu – especially now that Fu has been shown correct.

    Regards,
    John Cross

  3. JerryB
    Posted Aug 9, 2005 at 8:16 PM | Permalink

    John,

    It would be useful for you to include links , i.e. URLs, to your implied references.

  4. Steve McIntyre
    Posted Aug 9, 2005 at 8:27 PM | Permalink

    John C, I haven’t waded through the satellite literature and am fully preoccupied with multiproxy stuff; this was just a diversion. A first look at the satellite data with a simple c(1,0,1) arima model shows a lot of autocorrelation which would make trend estimation very iffy and with very wide confidence intervals. What is the position on the effect of autocorrelation in the literature? Steve

  5. Reid B
    Posted Aug 9, 2005 at 9:06 PM | Permalink

    Despite the heated rhetoric from the AGW crowd it is a fact that during the last seven years there has been global cooling relative to the 1998 temperature peak.

    I wonder what it would do to public and political opinion if that fact became common knowledge? If scientists were polled and asked “True or false, during the last seven years the global climate has cooled from the 1998 temperature peak” a large percentage would answer incorrectly. The point is that observation is not confirming the “consensus science” and political hysteria.

  6. Peter Hearnden
    Posted Aug 10, 2005 at 1:11 AM | Permalink

    Reid, Yes, and? Might ’98 have been exceptionally warm? I think so, infact it’s as plain as a pikestaff so.

    So, it’s a bit like you walking down a row of men who are gradually getting taller, passing a giant and then saying, triumphantly (since you don’t want to believe the men are geting taller) ‘see, relative to that man the most recent six men are getting shorter’. Of course you fail to mention all the six men are exceptionally tall themselves, just not so tall as the giant…

  7. Reid B
    Posted Aug 10, 2005 at 4:35 AM | Permalink

    Peter,

    Nobody knows if 1998 is an inflection point like the one that took place around 1970. Only time will tell. The GCM simulations are no more accurrate than flipping a coin when it comes to answering that question.

  8. TCO
    Posted Aug 10, 2005 at 5:37 AM | Permalink

    I agree that a single event, year, etc. is silly. A lot of this kind of PR chatter comes from the GW side as well. look at that big scary Powerpoint slide about increased storms this year on the RealClimate site.

  9. Paul Gosling
    Posted Aug 10, 2005 at 5:40 AM | Permalink

    Reid

    You do not need GCMs to realise that 1998 was not an inflection point. Try looking at the graph above.

  10. Dave Dardinger
    Posted Aug 10, 2005 at 6:58 AM | Permalink

    I realize it isn’t a fair test, but what would the warming trend if the 1998 spike were reversed about 0.0? I expect if there were still a warming trend it would be quite small. If nobody else chimes in I may calculate it myself once I get a chance to update my spreadsheet with the new data.

    But the point is that if the trend depends so strongly on one 2-year period, you shouldn’t make too much of it. In this respect it’s similar to the situation of the proxy studies and the bristlecone pines. Of course if we soon get another such spike the situation would change. But it the temperatures trend goes down then at some point the 1998 values actually would start working to produce a negative trend.

  11. Paul Gosling
    Posted Aug 10, 2005 at 7:12 AM | Permalink

    Dave D

    As we know why 1998 was so warm (large el nino) we can ignore it and look at the background trend, which is still upwards. Speculating what the trend might be if 1998 was very cold is a bit pointless as it wasn’t.

  12. Victor Irby
    Posted Aug 10, 2005 at 9:05 AM | Permalink

    I don’t know about anyone else, but what I see in the above graph is “noise”. If I tried to publish similar data in Physical Review claiming some trend it would be immediately rejected.

    Except for the spike near 1998, the temperature appears constant.

  13. John Finn
    Posted Aug 10, 2005 at 9:32 AM | Permalink

    While we’re speculating on “what ifs” … What if Mt Pinatubo hadn’t erupted when it did (in 1991). According to Realclimate this had a cooling effect of around 0.5 degrees. The most affected years being 1992, 1993 and 1994.

    This must ‘flatten’ the trend a bit.

    not forgetting El Chichon in 1982.

  14. Posted Aug 10, 2005 at 10:51 AM | Permalink

    re 2

    Reid B – Humm, I think a better analogy would be how S&C treated Fu – especially now that Fu has been shown correct.

    Here is a link to a comparison with Fu, although the trends are similar, the trend increase 5.1 -> 5.2 stems from a correction to the second part of the dataset, whereas Fu is mainly acting upon the El Chjichon and Pinatubo eruptions.

    http://www.ukweatherworld.co.uk/forum/forums/thread-view.asp?tid=23074&start=5

  15. Stephen H
    Posted Aug 10, 2005 at 10:53 AM | Permalink

    What upward trend? If it weren’t for the distorted scale, we wouldn’t be able to see any movement in temperature at all (“giants”? “tall men”?). These are changes in temperature that wouldn’t even register on my mercury yard thermometer. For what it’s worth, it’s clear to me there is no “trend” at all up the peak in 1998. After, there could be a “step” change of a fraction of a degree. Are people seriously trying to use this as support for AGW?

  16. John Hekman
    Posted Aug 10, 2005 at 12:52 PM | Permalink

    Stephen H: you say, “Are people seriously trying to use this as support for AGW?” The defenders of AGW are so eager to have the sat data agree with the highly questionable surface data that they are apparently embracing this sat data. Now that they cannot repudiate the sat data, it can be used to show that there is no evidence of AGW in it. So they have just shot themselves in the foot.

  17. Posted Aug 10, 2005 at 3:13 PM | Permalink

    Here are your 30 seconds of fame, Tom:

    All glory to Tom Rees who started this ukweatherworld thread. 🙂

  18. John A
    Posted Aug 10, 2005 at 3:50 PM | Permalink

    I heard recently from a scientist that since Pinatubo, there has been an unusually long quiet period to date regarding major volcanic eruptions. Of course eruptions are Poissonian in distribution, but still….

    I also think that 26 years is far too short to judge any sort of climatic trend.

  19. TCO
    Posted Aug 10, 2005 at 5:59 PM | Permalink

    It’s a 40% increase.

  20. Peter Hearnden
    Posted Aug 11, 2005 at 12:57 AM | Permalink

    Re #14. Reid, We KNOW that if you add CO2 to the atmosphere it WILL cause warming. FACT! Plenty of people, even sceptics, think it will be 1C – you can say that without even using a model just some maths! Now, is it reasonable to say that that warming will not cause further feedback effects – no it is not. You melt ice/ice caps, you expose ground the, ground warms faster that ice, = further warming. You warm the atmosphere, a warmer atmosphere can hold more WV = feedback warming. You melt permafrost – you then release another ghg CH4 = further warming. But…you warm the atmosphere = more or less clouds? Ahh, now that is the problem…you know the answer? Or are you a gambler?

  21. John A
    Posted Aug 11, 2005 at 1:15 AM | Permalink

    We KNOW that if you add CO2 to the atmosphere it WILL cause warming. FACT!

    No we don’t. The mere fact that you state this indicates a profound inability to come to terms with the concept of non-linearity.

    The rest of your argument falls flat in consequence

  22. Tom Rees
    Posted Aug 11, 2005 at 6:12 AM | Permalink

    Thanks Hans – me ole mucker 🙂

  23. Reid B
    Posted Aug 11, 2005 at 6:23 AM | Permalink

    Re #21 “You melt ice/ice caps, you expose ground the, ground warms faster that ice, = further warming.”

    The ice caps are not melting as AGW promoters claim. The arctic is warming but the antarctic is cooling at a rapid rate. The antarctic ice cap is expanding at a rapid rate and that is a FACT. Satellite radar telemetry punched yet another hole in AGW theory. The observations are not conforming to the theory.

    When AGW promoters talk about the antarctic warming they point to the tip of the antarctic peninsula that has warmed due to ocean current changes. That area comprises 2% of the antarctic land mass. The vast majority of antarctica is cooling. Explain that AGW believers.

    If you polled scientists and asked the following question most would get the answer wrong. True or false, antartica is cooling and the antarctic ice cap is growing at a rapid pace.

  24. Peter Hearnden
    Posted Aug 11, 2005 at 2:48 PM | Permalink

    Reid, ” True or false, antartica is cooling and the antarctic ice cap is growing at a rapid pace.”. Actually, given the paucity of data from Antarctica to say with confidence it’s warming or cooling is difficult. I do grant you it’s an odd isolate place, it might be a the last place to show effects of warming, and some parts do seem to be cooling. I also seem to remember there is evidence of ice accumulating, probably due to more moisture being available in this warmer world.

    I do think, to be clear, that ice caps (primarily Greenland) melting is a future thing. I hope it doesn’t start because if it does it probably wont stop.

    John A, you need to come to terms with CO2 being a ghg – if you can do that then you can progress a little.

  25. TCO
    Posted Aug 11, 2005 at 3:06 PM | Permalink

    If the ice shrinks its from GW. If it advances then its from GW (more moisture in the air). Convenient.

  26. John Cross
    Posted Aug 11, 2005 at 4:14 PM | Permalink

    Hans:

    Regarding FU, are you saying that Fu’s correction is not valid due to enhanced cooling of the stratosphere by volcanic eruptions?

  27. J. Sperry
    Posted Aug 12, 2005 at 10:12 AM | Permalink

    Re: #25

    John A, you need to come to terms with CO2 being a ghg – if you can do that then you can progress a little.

    If you read John A’s comment again in #22, you will see that the key is not whether CO2 is a greenhouse gas (is most certainly is), the key is in the non-linearity (among other things) of the system.

  28. TCO
    Posted Aug 12, 2005 at 10:13 AM | Permalink

    What’s up, Jim?

  29. Michael Jankowski
    Posted Aug 12, 2005 at 12:57 PM | Permalink

    You melt ice/ice caps, you expose ground the, ground warms faster that ice, = further warming.

    I don’t know if “ground warms faster than ice,” but I think it’s irrelevant.

    I think what you’re trying to say is that the ice has a higher albedo than the ground (or water) beneath it, which means it reflects more radiation. Therefore, as ice coverage is lost, the Earth’s overall reflective albedo decreases and results in increased warmth (provided all other conditions stay roughly the same, of course).

  30. Posted Aug 12, 2005 at 1:51 PM | Permalink

    re: #27
    According to S&C the correction applied by Fu et al. for cooling is too much.

  31. Posted Aug 12, 2005 at 2:05 PM | Permalink

    re #19
    Here are graphs of Volcanic aerosols:

    There was a quite big gap between Katmai(Alaska, 1912) and Gunung Agung (Bali, 1963)

  32. Posted Aug 13, 2005 at 2:25 AM | Permalink

    I graphed the monthly data of Jones and MSU 5.2, see for yourself.
    http://www.ukweatherworld.co.uk/forum/forums/thread-view.asp?tid=23074&posts=22#M259619

  33. Posted Aug 16, 2005 at 3:53 AM | Permalink

    In 1998 Fred Singer reassured the House Small Business Committee that “The climate is not warming…”
    On his website, Singer claims that “…since 1940, weather satellites, tree ring data, and corrected thermometer readings all agree that climate has not warmed–even though CO2 levels rose.” http://www.sepp.org/faq.html
    In April 2005, Fred Singer accepted his “Flat Earth Society” award with this comment:

    “What matters are facts based on actual observations. And as long as weather satellites show that the atmosphere is not warming, I cannot put much faith into theoretical computer models that claim to represent the atmosphere but contradict what the atmosphere tells us.”

    Now comes research that uncovers errors in the satellite and weather balloon data, which explain the discrepancy between reports showing that the atmosphere is not warming, even while temperatures at the Earth’s surface are rising at an accelerating rate.

    A report by scientists at Yale University and the National Oceanic and Atmospheric Administration (NOAA) finds that the effect of the sun’s heat on weather balloons largely accounts for a data discrepancy that global warming deniers have long hung their hat on… http://www.csmonitor.com/2005/0422/p08s01-coop.html

    Three papers published in Science Express “strongly suggests that there is no longer any fundamental discrepancy between modeled and observed temperature trends in the tropical atmosphere” according to Benjamin Santer, lead author of the paper and a scientist in LLNL’s Program for Climate Model Diagnosis and Intercomparison.
    http://www.eurekalert.org/pub_releases/2005-08/yu-eit080805.php

    Now, why would Singer put his faith in weather satellites, when the satellite data have long been known to be subject to potential errors in data analysis? Because that’s his job, as a vocal global warming denier, media spokesperson and the founder of an anti-global warming think tank.

    Facts based on observations are consistent with the theory of global warming. Singer’s penchant for categorical denials of any evidence of global warming is at odds with observed facts. Singer’s comments illustrate the bankruptcy of credibility that the skeptics have created for themselves by promoting uncertainties in the science as arguments in their favor.

  34. Posted Aug 17, 2005 at 5:29 AM | Permalink

    This reminds me of the argument over how many angels could be fitted on a pin head.

    One non urban temperature recording station ( remote as you wish) that shows either steady or decreasing mean temperature per unit of time is sufficient to sink the good ship global warming.

    May I suggest Mars might, with its atmosphere of 95% CO2, with negligible “greenhouse effect” might add a new perspective?

    Debate over decimals of temperature when the historica data themeselves were never measured to such a precision makes the whole debate much like a Shakespearian Tragedy.

  35. Reid B
    Posted Aug 18, 2005 at 10:55 AM | Permalink

    #34 “…the Earth’s surface are rising at an accelerating rate.”

    The newly revised satellite data shows with certainty that 1998 was the peak warm year and the planet has undergone relative global cooling in the last 7 years. Hardly what the alarmists were predicting 7 years ago.

    The planet warmed from 1900 till 1940 then cooled till 1970 then warmed till 1998 and is now cooling again. Can anyone claim with any degree of certainty when the 1998 peak will be surpassed or if it will be surpassed at all in the next hundred years? Nobody knows with any certainty since we can’t know future solar irradiance at todays level of scientific understanding.

  36. J. Sperry
    Posted Aug 23, 2005 at 2:07 PM | Permalink

    Re: #35

    One non urban temperature recording station ( remote as you wish) that shows either steady or decreasing mean temperature per unit of time is sufficient to sink the good ship global warming.

    While I do not want to be accused of being in the alarmist camp, the above statement certainly mischaracterizes the debate. Current global warming theory does not require that every square inch of the earth be involved in the warming. Climate scientists of all stripes recognize that a single temperature station can neither verify nor disprove anthropogenic global warming. Your argument is properly categorized as “cherry-picking” and should be ridiculed by both sides.

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