Dr. Roy Spencer’s Sea Surface Temperatures

Guest Post by Willis Eschenbach

Over at Roy Spencer’s excellent web site, Dr. Roy has a post up showing a sea surface temperature (SST) anomaly calculated from AMSR-E, TMI, and WindSat. Here’s his post of the results:

spencer global sst amsr-e TMIFigure 1. Global Microwave Sea Surface Temperature Update for Feb. 2013: -0.01 deg. C

Regarding these results, Dr. Roy says:

The anomalies are computed relative to only 2003-2006 because those years were relatively free of El Nino and La Nina activity, which if included would cause temperature anomaly artifacts in other years. Thus, these anomalies cannot be directly compared to, say, the Reynolds anomalies which extend back to the early 1980s.

So I figured I’d give him a hand by using the same 2003-2006 monthly anomaly baseline for the Reynolds Optimal Interpolation (OI) sea surface temperature, so we could have a longer dataset, and to see how his results compare to the Reynolds OI data.

I started by datapointing Dr. Roy’s data. I digitized it, and entered it into Excel.

Then I downloaded the Reynolds SST data (actual, not anomalies) from KNMI for the same area of the planet, 60°N to 60°S. Finally, I figured the monthly averages for the 2003-2006 period, and subtracted them from the Reynolds actual data to give the anomalies. Figure 2 shows the results:

sea surface temperature comparison 60nsFigure 2. Reynolds OI and Spencer Microwave SST measurements.

Not much to say, except that Dr. Roy’s results agree pretty well with the Reynolds OI data, and that there’s been no significant increase or decrease in SST in the last 15 years or so …

All data and calculations are here as an Excel spreadsheet.

My best regards to everyone,

w.

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55 Responses to Dr. Roy Spencer’s Sea Surface Temperatures

  1. bones says:

    Willis, thanks for the comparison. I wondered about it but was too lazy to do what you have done.

  2. cui bono says:

    Nice one Willis. Another flatline.

    So the Godzillian gigajoules of ‘missing heat’ hiding down in the Mariana Trench haven’t had any effect yet? (/sarc).

  3. Barry Cullen says:

    Willis,
    From your recent posts, you must still be retired.

  4. EJT says:

    As an “outsider” when and why did this habit of calling the variation from mean value an “anomaly” start ? Surely you expect there to be variations, so there is nothing anomalous about them. Was this started by the AWG crowd to make the lay reader think “there is something wrong” ?

  5. more soylent green! says:

    Does anybody have an overlay that shows sea surface temperature and HadCRUT, GissTemp, and others? I’d like to see how the data compares over time.

  6. David S says:

    It’s a travesty. Maybe it was never there.
    Thanks Willis, yet again.

  7. Willis Eschenbach says:

    Barry Cullen says:
    March 6, 2013 at 9:28 am

    Willis,
    From your recent posts, you must still be retired.

    I wish, but no … just self-employed, and still building houses.

    That’s in part why this post is so short …

    w.

  8. Tim Ball says:

    Why only from 60N to 60S?

    I appreciate the results are pleasing as they relate to the levelling seen in the surface temperature data of the last 16 years, but I know from working in higher latitude waters how dramatically different polar waters are from subtropical waters. For example, the boundary between the dark bottle green waters of the Labrador Current and the azure blue waters of North Atlantic Drift (Gulf Stream) is very visible on most occasions. The collision coincides with the foggiest region of the world south of Newfoundland.

    Surely, if you are going to use the word ‘global’ you must include the regions from 60N and 60S to the Poles. It is especially important because the IPCC claim warming will be greater in those latitudes. Milankovitch also acknowledged the importance of changing obliquity of the ecliptic in these latitudes.

  9. wbrozek says:

    more soylent green! says:
    March 6, 2013 at 9:39 am
    Does anybody have an overlay that shows sea surface temperature and HadCRUT, GissTemp, and others? I’d like to see how the data compares over time.

    Is this what you wanted? If not, you can start with this and add or delete as you wish.

    http://www.woodfortrees.org/plot/hadcrut3gl/from:1997.33/trend/plot/gistemp/from:2001.33/trend/plot/wti/from:2000.9/trend/plot/hadsst2gl/from:1997.1/trend/plot/hadcrut4gl/from:2000.8/trend/plot/hadcrut3gl/from:1997.33/plot/gistemp/from:2001.33/plot/wti/from:2000.9/plot/hadsst2gl/from:1997.1/plot/hadcrut4gl/from:2000.8/plot/rss/from:1997/plot/rss/from:1997/trend/plot/uah/from:2008.5/plot/uah/from:2008.5/trend

  10. Gneiss says:

    Willis writes,
    “Dr. Roy’s results agree pretty well with the Reynolds OI data, and that there’s been no significant increase or decrease in SST in the last 15 years or so …”

    The “or so” part is not true. The increase in Reynolds SST (your data) appears not significant if you pick 1998 as the start year, or 1996, 1997, or 2000. But it is significant if you pick 1999, 2001, 2002, or 2003 as start years (or anything before 1996). This leads into that whole discussion about cherry picking, and why it’s a poor way to draw conclusions.

  11. Paul Matthews says:

    And here for comparison is the latest SST data from the UK Hadley Centre

    https://www.maths.nottingham.ac.uk/personal/pcm/hadsst.png

  12. Jon in TX says:

    Just a simple question. Based on Bob Tisdale’s articles, The warming/colling waters of ENSO seem to migrate based on various ocean currents, and that latent heat from El Nino takes quite a while to dissipate. If true, then how can anyone assume that certain years are “relatively free” of ENSO contamination? Maybe I’m missing something.

  13. Andy Wilkins says:

    But Willis, where are the hockey stick temperatures? I thought all that ‘missing heat’ was swirling around in the sea?
    Mike, Jim and Al won’t be pleased at all ;)

  14. Tom_R says:

    Tim Ball says:
    March 6, 2013 at 10:01 am
    Why only from 60N to 60S?

    I would think it’s because much of the ocean near the poles is covered with ice at least for part of the year, so the water temperature is missing for months at a time there, and that time varies from year to year.

  15. kadaka (KD Knoebel) says:

    Let’s see, run the checklist:

    1. Willis
    2. Ocean temperatures
    3. Nothing significant happening globally (no sign of global warming)

    Yup, we’re about ten posts from the first commenter with some version of “Well Willis, if you were smart and/or educated enough to understand the uncertainties/error margins and/or properly compute the (statistics, trends, differentials) then You would know the real truth is…

    Bonus points for bringing up the ARGO data and trying to reduce his obvious glaring overwhelming ignorance of how the floats operate and the quality of those results, and for mentioning how the truth of the oceans is clearly revealed by Levitus 2012, of which perhaps someday Willis will make the tremendous personal sacrifice of someday schlepping down to the public library often enough that perhaps he could review and acquaint himself with that fine scholarly peer-reviewed expert document.

  16. Willis Eschenbach says:

    Gneiss says:
    March 6, 2013 at 10:04 am

    Willis writes,

    “Dr. Roy’s results agree pretty well with the Reynolds OI data, and that there’s been no significant increase or decrease in SST in the last 15 years or so …”

    The “or so” part is not true. The increase in Reynolds SST (your data) appears not significant if you pick 1998 as the start year, or 1996, 1997, or 2000. But it is significant if you pick 1999, 2001, 2002, or 2003 as start years (or anything before 1996). This leads into that whole discussion about cherry picking, and why it’s a poor way to draw conclusions.

    I was being quite conservative. If you adjust for autocorrelation using the method of Nychka, there’s been no significant increase in the Reynolds SST database since just after the beginning in 1981.

    Cherry picking? Sorry, no way, I don’t engage in that kind of thing. The problem is the autocorrelation of the SST database is very, very high (0.94). As a result, we expect it to contain quite wide swings compared to a random walk … and that’s exactly what it’s done. The lowest p-value for the entire period is 0.048, barely significant at the weak level (p less than 0.05), and that is the only significant value for the entire dataset. If we start with the second month, the p-value is already rising, it’s 0.502, not significant, and it just gets worse from there.

    So yes, what I said is not only true for the last 15 years—it’s true for the whole Reynolds dataset.

    w.

  17. Arfur Bryant says:

    more soylent green! says:
    March 6, 2013 at 9:39 am
    Does anybody have an overlay that shows sea surface temperature and HadCRUT, GissTemp, and others? I’d like to see how the data compares over time.

    MSG,

    The nearest I can suggest is the following graphs from the excellent http://www.climate4you.com

    http://www.climate4you.com/images/HadSST3%20GlobalMonthlyTempSince1979%20With37monthRunningAverage.gif

    http://www.climate4you.com/images/HadCRUT4%20GlobalMonthlyTempSince1979%20With37monthRunningAverage.gif

    http://www.climate4you.com/images/GISS%20GlobalMonthlyTempSince1979%20With37monthRunningAverage.gif

    Ole Humlum has deliberately chosen the same timescale for each graph for ease of comparison. Elsewhere he has a combined graph of HadCRut3 and SST but for the Tropics only.

    Hope this helps. There is a mass of info on the site.

  18. kadaka (KD Knoebel) says:

    From Willis Eschenbach on March 6, 2013 at 9:51 am:

    I wish, but no … just self-employed, and still building houses.

    Obviously it is past time for you to combine your skills and main passions, and design and build houseboats.

    You’re in California, you have a ready market willing to accept a houseboat as the ultimate hedge against future rising world oceans, even if they currently live ten miles inland. Because after the rise they expect to be on the shoreline.

    The fun part is working in “rocket stove” heaters, for cooking, and for driving a boiler for propulsion and electricity generation. Then they can immediately recycle cardboard packaging, paper, scrap wood, driftwood. Very Green.

    How far away from the coast do you have to be moored at night for California to not charge resident taxes?

  19. Phil. says:

    Tom_R says:
    March 6, 2013 at 10:53 am
    Tim Ball says:
    March 6, 2013 at 10:01 am
    Why only from 60N to 60S?

    I would think it’s because much of the ocean near the poles is covered with ice at least for part of the year, so the water temperature is missing for months at a time there, and that time varies from year to year.

    In their microwave sounding product RSS don’t include any areas where there is surface ice because of interference with the signal I would assume that RSS restrict the use of this data for the same reason.

  20. more soylent green! says:

    wbrozek says:
    March 6, 2013 at 10:01 am
    more soylent green! says:
    March 6, 2013 at 9:39 am
    Does anybody have an overlay that shows sea surface temperature and HadCRUT, GissTemp, and others? I’d like to see how the data compares over time.

    Is this what you wanted? If not, you can start with this and add or delete as you wish.

    I am looking for a chart that would show how well or how poorly the various global temp datasets correlated, especially and divergence with SST.

    I think that’s what the link you provided gives me, but I haven’t had any time to look at it in depth.

    Thanks

  21. Willis Eschenbach says:

    Tim Ball says:
    March 6, 2013 at 10:01 am

    Why only from 60N to 60S?

    I appreciate the results are pleasing as they relate to the levelling seen in the surface temperature data of the last 16 years, but I know from working in higher latitude waters how dramatically different polar waters are from subtropical waters. For example, the boundary between the dark bottle green waters of the Labrador Current and the azure blue waters of North Atlantic Drift (Gulf Stream) is very visible on most occasions. The collision coincides with the foggiest region of the world south of Newfoundland.

    Surely, if you are going to use the word ‘global’ you must include the regions from 60N and 60S to the Poles. It is especially important because the IPCC claim warming will be greater in those latitudes. Milankovitch also acknowledged the importance of changing obliquity of the ecliptic in these latitudes.

    Thanks, Tim, sorry I missed your question. I agree with you.

    However, to some degree, it’s a difference that doesn’t make a big difference. This is because there’s not a whole lot of ocean near the poles, only about 10% of the area.

    In any case, here’s the difference:

    As you would expect, adding more data decreases the variance, particularly in this case as the temperature of the water near the ice doesn’t vary much. Other than that, though, there’s little difference between the two—correlation is 0.9956 …

    Regards,

    w.

  22. Willis Eschenbach says:

    kadaka (KD Knoebel) says:
    March 6, 2013 at 11:02 am

    Let’s see, run the checklist:

    1. Willis
    2. Ocean temperatures
    3. Nothing significant happening globally (no sign of global warming)

    I’m not clear what this “checklist” is supposed to represent … other than your ideas. Totally unclear, sorry. Am I supposed to have said there’s no sign of global warming? If so, over what time period? Or is that your claim?

    Useless.

    Yup, we’re about ten posts from the first commenter with some version of “Well Willis, if you were smart and/or educated enough to understand the uncertainties/error margins and/or properly compute the (statistics, trends, differentials) then You would know the real truth is…”

    Whose post are you talking about, and why on earth aren’t you QUOTING or LINKING to whatever you’re on about? This is just a pathetic attempt at character assassination.

    Bonus points for bringing up the ARGO data and trying to reduce his obvious glaring overwhelming ignorance of how the floats operate and the quality of those results, and for mentioning how the truth of the oceans is clearly revealed by Levitus 2012, of which perhaps someday Willis will make the tremendous personal sacrifice of someday schlepping down to the public library often enough that perhaps he could review and acquaint himself with that fine scholarly peer-reviewed expert document.

    You are the first person to discuss either Argo or Levitus on this thread, which is about the Reynolds and the Spencer SST measurements … so I have to ask, are you drunkblogging? Have you posted this on the wrong thread? What does the Argo data have to do with this thread?

    As to Levitus, if you have a page number and a quote I’m happy to discuss exactly what you are referring to. At present, your pointing at the entire document and saying that the answer to all mysteries is in there somewhere is useless handwaving and political posturing.

    If you object to my words, QUOTE THEM and tell me exactly where I’m wrong. Don’t bother me with your bullshit checklists and vague claims, that kind of thing is as useless as a trailer hitch on a bowling ball.

    I know you can do much better than that whole meaningless farrago, KD.

    All the best,

    w.

  23. Gneiss says:

    Willis writes,
    “I was being quite conservative. If you adjust for autocorrelation using the method of Nychka, there’s been no significant increase in the Reynolds SST database since just after the beginning in 1981.”

    Your adjustment increases the standard errors so much that nothing is significant over this time frame. The regression trends remain the same. As does the visually obvious increase in that graph.

    Why not take a modern approach and model autocorrelation directly? Doing so gives a different result.

  24. Nick Stokes says:

    more soylent green! says:March 6, 2013 at 9:39 am
    “Does anybody have an overlay that shows sea surface temperature and HadCRUT, GissTemp, and others? I’d like to see how the data compares over time.”

    Here is one. You can add or remove data as you wish.

  25. Nick Stokes says:

    Sorry, link got messed there. Hope this works.

  26. kadaka (KD Knoebel) says:

    Re Willis Eschenbach on March 6, 2013 at 12:45 pm:

    Oh Willis, you’re wrapped entirely too tight these days.

    Going off the recent comments and posts, the checklist is everything required for someone to post some odious comment questioning your competency/education/intelligence/breeding “regarding these matters”.

    With such wonders as “trying to educate you” on the ARGO floats, although you’ve written entire considered posts on them,

    And recently Levitus was trotted out as something “you should educate yourself about”, although you have also written posts about Levitus 2012.

    My apologies, but after so many recent examples of people wanting to “educate” you on these subjects after you’re already demonstrated your knowledge of them, I find it entertaining when whichever-idiots show up wanting you to “educate yourself” on these things Again!

    Will they always be doing this?

  27. David A. Evans says:

    kadaka (KD Knoebel) says: That’s the way I interpreted your original comment and was wondering what Willis was upset about.
    DaveE.

  28. So, in other words, in over 30 years Sea Surface Temperatures have stayed within a range of 0.6 C, and are currently slightly under the average. What about all that “warm surface water” that fed Katrina, Sandy, and all the other Superstorms such as we have “never had before (sarc)?” THAT meme has taken a hard blow here.

    Somebody needs to find a way to communicate this crucial and much-obfuscated information to “Low Information Voters.” Another nail in the coffin of CAGW!!!

    Willis, are you comfortable with knowing the temperature of the surface of the ocean to within 0.1 C? If you are, it seems you should be more comfortable with knowing the average temperature of the oceans to within 0.01 C, as many discussed with the ARGO thermometers. Water takes a lot more energy to change its temperature than air does…

  29. Bob Tisdale says:

    And for those who missed the link Monday on the TLT thread, here’s a link to the preliminary Reynolds sea surface temperature update for February 2013:
    http://bobtisdale.wordpress.com/2013/03/04/preliminary-february-2013-sea-surface-temperature-anomaly-update/

  30. Andy says:

    Hi Willis,
    I suspect the character assassination is driven from a blog post by PZ Myers, where the fool criticises this site and you in particular. Hilariously the fool did not realise your posts sometimes get published in journals.

    Kind regards.

  31. Bob Tisdale says:

    Willis, to expand on your reply to Tim Ball, global sea surface temperatures (90S-90N) are warming at a slower rate than the latitudes used by you and Roy Spencer (60S-60N):
    http://i49.tinypic.com/349cw9i.jpg
    Keep in mind, while the Arctic Ocean may be warming…
    http://bobtisdale.files.wordpress.com/2013/02/13-arctic.png
    …the Southern Ocean covers more surface area and it’s cooling:
    http://bobtisdale.files.wordpress.com/2013/02/14-southern.png
    Graphs are from the January update:
    http://bobtisdale.wordpress.com/2013/02/11/january-2013-sea-surface-temperature-sst-anomaly-update/

    Regards

  32. atheok says:

    “David A. Evans says:
    March 6, 2013 at 1:44 pm
    kadaka (KD Knoebel) says: That’s the way I interpreted your original comment and was wondering what Willis was upset about.
    DaveE.”

    With the three items checklist, I was on board with Kadaka spiking the troll types who never seem to remember real science details and harp on rebutted research as if it’s cutting edge truth, ike hockey sticks, Antarctica peninsula temps averaged over Antarctica or how a tiny fraction of a degree ocean temperature is proof of man caused global warming.

    I didn’t follow the checklist logically into the following paragraphs; even afterI reading it through several times. I was especially puzzled as those paragraphs were, to me, distinctly un-Kadaka like.

    Overall, I was left with the impression overall that Kadaka was challenging Willis, so I understand Willis’s response.

    Perhaps rephrasing the paragraphs would’ve helped; especially as their lack of clarity and especially constinuity were not Kadaka’s style either, again my personal opinion.

    A /sarc would’ve helped.

  33. Bob Tisdale says:

    more soylent green! says: “Does anybody have an overlay that shows sea surface temperature and HadCRUT, GissTemp, and others? I’d like to see how the data compares over time.”

    From a post in April 2012, I’ve got a comparison of CRUTEM4 and HADSST3:
    http://bobtisdale.files.wordpress.com/2012/04/figure-101.png
    And the difference:
    http://bobtisdale.files.wordpress.com/2012/04/figure-112.png
    They’re from this post:
    http://bobtisdale.wordpress.com/2012/04/28/a-closer-look-at-crutem4-since-1975/

  34. Willis Eschenbach says:

    kadaka (KD Knoebel) says:
    March 6, 2013 at 1:12 pm

    Re Willis Eschenbach on March 6, 2013 at 12:45 pm:

    Oh Willis, you’re wrapped entirely too tight these days.

    Clearly I totally misread your intent, my apologies.

    You might, however, profit by [sarc] tags in the future. I get attacked relentlessly for things people imagine I said. The problem is, no matter how outrageous and unbelievable you think you are being, I’ve likely been attacked by someone seriously saying the same thing

    Again, my apologies for my response.

    w.

  35. Tim Ball says:

    Willis
    I cannot accept your argument about the amount of ocean within 60° of the poles. It is partly true for the Antarctic, but not for the Arctic. Consider there is some 21 million square kilometers within the Arctic Circle and that includes very large important areas of oceans, such as a large section of the North Atlantic. Expand that area out to 60°N and an even greater area of ice free ocean is encompassed. You can see the area within the Arctic Circe on this map;

    http://tinyurl.com/chyj8vf

    Then add a further five degrees of latitude and you can see how the area expands significantly. There is also the transfer of heat from the relatively warmer water through the ice to heat the cold air.

  36. Willis Eschenbach says:

    Gneiss says:
    March 6, 2013 at 1:00 pm

    Willis writes,

    “I was being quite conservative. If you adjust for autocorrelation using the method of Nychka, there’s been no significant increase in the Reynolds SST database since just after the beginning in 1981.”

    Your adjustment increases the standard errors so much that nothing is significant over this time frame. The regression trends remain the same. As does the visually obvious increase in that graph.

    Why not take a modern approach and model autocorrelation directly? Doing so gives a different result.

    Mmmm … thanks, Gneiss, nice screen name by the way. The problem is that claiming “a different result” doesn’t tell me much. Actually, it tells me nothing.

    More to the point, I’ve looked at that. In the past, I’ve run a number of tests comparing Nychka’s adjustment versus the actual variations in ARIMA random autocorrelated data. I investigated various combinations of AR (auto regression) and MA (moving average), particularly in the range common with climate variables. Curiously, these often run high AR (≈ 0.8) and negative MA (≈ -0.3).

    I haven’t run this particular dataset, but I’ve never found Nychka’s algorithm to be too far out, it gives good results.

    Finally, I have provided my data and spreadsheet above in the head post. If you think there’s a better way, I invite you to do what I did. Use that same data, do your own analysis, and post the results on the web.

    All the best,

    w.

    PS—Assuming I haven’t considered something is not infrequently a mistake …

  37. kadaka (KD Knoebel) says:

    From atheok on March 6, 2013 at 2:41 pm (quoted out of sequence):

    A /sarc would’ve helped.

    We were told long ago the sarc tag would be coming out with the next HTML release, but for HTML5 it never made it out of beta. Maybe next time.

    (…) I was especially puzzled as those paragraphs were, to me, distinctly un-Kadaka like.

    Perhaps rephrasing the paragraphs would’ve helped; especially as their lack of clarity and especially constinuity were not Kadaka’s style either, again my personal opinion.

    I was not aware my “style” was all that distinctive. I’ve even been trying to tighten it up somewhat, make it more “standard”.


    Overall, I was left with the impression overall that Kadaka was challenging Willis, so I understand Willis’s response.

    In a mocking imitation of the usual trollish “challenges”, that was highly exaggerated, that’s what I was aiming for and that’s how it sounded to me.

    That it so strongly got Willis’ goat, well, that was unexpected. I thought he’d know me better by now, especially since anything I write is sarc as the default formatting.

    It’s also strangely reinforced the many warnings of the farming relatives to avoid goats altogether when I asked. Which was saddening, as the TV had led me to believe a few of the small ones would be excellent self-directed self-refueling combination lawnmowers/weed-whackers. I likely wouldn’t have had to even fence or pen them in either since, well, if those invisible fence and shock collar combos can contain a St. Bernard or pit bull…

  38. Arno Arrak says:

    Interesting. Apparently measured in the Eastern equatorial Pacific. Shows four El Nino peaks in the eighties and nineties, the super El Nino of 1998, the twenty-first century high, the 2008 La Nina, and the 2010 El Nino. The last one is higher than the 1998 super El Nino but we are talking of SST, not atmospheric temperatures, and different sources of data. The correspondence between SST and atmospheric temperature is due to the fact that El Nino waves that traverse the Pacific along the equatorial countercurrent wash ashore in South America, spread out along the coast in both directions, and warm the air above. It is this heat transfer that generates the ENSO oscillation. As you can see, the twenty first century high is caused by a missing La Nina which got blotted out by the huge amount of warm water the super El Nino carried across the Pacific. Read pp. 23-29 in “What Warming?”

  39. kadaka (KD Knoebel) says:

    From Willis Eschenbach on March 6, 2013 at 4:01 pm

    Clearly I totally misread your intent, my apologies.

    Again, my apologies for my response.

    Don’t apologize unless it means something. Since I took no offense and had laughed off your response as soon as I saw it, knowing all along it was a simple misunderstanding, nothing needed apologizing for… How could your apologies have meant anything?

    Simple question, straight up: Can you seriously imagine either of us going hard against the other, in a way that is meant to be taken serious? Maybe if you write up a definitive well-researched work recommending the fast breeding of brown babies by parents force-fed a vegan diet as an emergency meat supply, then I might have a few choice words for you. Especially if you go against your long-professed ethics and don’t archive your data, with instant web access.

  40. David A. Evans says:

    kadaka (KD Knoebel). Your sense of humour is going to get you in trouble one day. ;-)
    DaveE.

  41. ferd berple says:

    Willis Eschenbach says:
    March 6, 2013 at 11:23 am
    Cherry picking? Sorry, no way, I don’t engage in that kind of thing.
    ============
    Agreed. A toss of the dice/coin no memory. No matter what you throw, your next toss is not affected. This is the statistics you learn in school.

    Temperature is a different matter. A hot day/month/year is more likely to be followed by another hot day/month/year than it is to be followed by a cold day/month/year. We can see it in the data. This is auto-correlation. The data depends on the past – it has a memory.

    Thus, when people talk about statistical significance, they must first take the time to understand statistics. The temperature was a coin toss or a throw of the dice then the change is significant. However, since temperature is highly auto-correlated then the change is not significant.

  42. Willis Eschenbach says:

    Gneiss, I did the analysis you suggested. Remember that Nychka indicated, the full length of the data (375 months = 31+ years) is significant, but not by much.

    Here’s the usual measure of whether the trend is significant. Below is looking at the last 300 months (25 years) of data, since the start of 1988. Temperatures and dates are in two variables cleverly named mytemps & mydates.

    lm(formula = mytemps ~ mydates)
    Coefficients:
                Estimate Std. Error t value Pr(>|t|)    
    (Intercept) 5.042264   2.387385   2.112   0.0355 *  
    mydates     0.007675   0.001193   6.432 5.01e-10 ***
    ---
    Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 

    Note the claim that the result is very significant. Also, the slope is + 0.0076°C/year.

    To do the analysis, I first determined the best fit AR and MA coefficients for the full Reynolds data.
    These turned out to be AR = 0.76 and MA = 0.64, viz

    Call:
    arima(x = thetemps, order = c(1, 0, 1))
    
    Coefficients:
             ar1     ma1  intercept
          0.7590  0.6358    20.3639
    s.e.  0.0352  0.0330     0.0248
    
    sigma^2 estimated as 0.005084:  log likelihood = 457.14,  aic = -906.28

    Then I generated a thousand random ARIMA datasets with the standard deviation, AR, and MA, of the Reynolds OI data. I looked at the slopes of the 1,000 datasets, to see how common it was to find a slope of 0.008°C per year (the slope of the Reynolds global SST data).

    I found that for a p-value less that 0.05, the usual climate science standard for kinda significance, you need to go back about 300 months. That is 25 years … anything less than that, according to the Monte Carlo analysis, isn’t significant.

    > datacount=1000
    > recordlen=300
    > myrand=arima.sim(list(ar=.759,ma=0.6358),n=recordlen*datacount)
    > mym=matrix(myrand,nrow=recordlen)
    > mym=mym*sd(thetemps)/sd(myrand)
    > mydata=apply(mym,2,getslope) # mydata is 1,000 slope results
    > mean(mydata)
    [1] 9.498117e-05
    > round(sd(mydata)*1.96,4)
    [1] 0.0074

    The final number is the p = 0.05 slope. If the test slope is higher than that 0.0074°C/yr, it’s significant.

    Now, notice that the slope over that 25 year period (shown above) is 0.0077°C/yr … just barely significant. And as you go shorter, things get worse. So rather than the trend since 1988 being very, very significant as we’d calculate without autocorrelation, that trend in the Reynolds data of twenty-five years is just achieving significance.

    So indeed, I was right that there is no significant trend going back 15 years or so … to get a statistically significant trend you need to start about 25 years ago.

    All the best, thanks for the suggestion.

    w.

  43. Willis Eschenbach says:

    Tim Ball says:
    March 6, 2013 at 4:08 pm

    Willis
    I cannot accept your argument about the amount of ocean within 60° of the poles.

    Thanks, Tim. It’s not an argument. It’s a measurement, by 5° latitude band, of the ocean area.

    Here’s the data:

    Center Latitude , Global Ocean Area %
    87.5 ,0.27%
    82.5 ,0.69%
    77.5 ,1.01%
    72.5 ,1.19%
    67.5 ,0.65%
    62.5 ,0.85%
    57.5 ,1.50%
    52.5 ,1.52%
    47.5 ,1.82%
    42.5 ,2.32%
    37.5 ,2.75%
    32.5 ,2.98%
    27.5 ,3.25%
    22.5 ,3.68%
    17.5 ,4.15%
    12.5 ,4.58%
    7.5 ,4.61%
    2.5 ,4.82%
    -2.5 ,4.64%
    -7.5 ,4.67%
    -12.5 ,4.77%
    -17.5 ,4.46%
    -22.5 ,4.28%
    -27.5 ,4.26%
    -32.5 ,4.35%
    -37.5 ,4.54%
    -42.5 ,4.36%
    -47.5 ,4.04%
    -52.5 ,3.68%
    -57.5 ,3.29%
    -62.5 ,2.82%
    -67.5 ,1.91%
    -72.5 ,0.85%
    -77.5 ,0.32%
    -82.5 ,0.12%
    -87.5 ,0.00%

    Best regards,

    w.

  44. Lesley McKay says:

    kadaka
    let it be mate, you are over egging it

  45. Willis Eschenbach says:

    kadaka (KD Knoebel) says:
    March 6, 2013 at 5:23 pm

    From Willis Eschenbach on March 6, 2013 at 4:01 pm

    Clearly I totally misread your intent, my apologies.

    Again, my apologies for my response.

    Don’t apologize unless it means something. Since I took no offense and had laughed off your response as soon as I saw it, knowing all along it was a simple misunderstanding, nothing needed apologizing for… How could your apologies have meant anything?

    kadaka, I had replied to this, and the mods snipped my response … likely wisely, I’m not gonna complain about krool censorship. Because when I first read your paragraph above, I waxed wroth, and my blood was mightily angrified.

    So let me explain my position less passionately than before.

    First, I apologized because I’d misunderstood you. I don’t give a damn if you think there’s nothing to apologize for, your opinion of my actions is totally beside the point. I’m not apologizing because you think I should apologize. I’m apologizing because I think I should, because in my world I’ve concluded that I’ve done something wrong. Your judgements and opinions of that conclusion are immaterial.

    It’s generally considered polite to simply respect a man’s decision when he feels he should apologize, and not try to substitute your own judgement about whether he should apologize or not. He’s apologizing for his reasons, not yours.

    Next, when I apologize, by god, it means something. I do not apologize meaninglessly or falsely. It’s never just words, I don’t play those games.

    Now, I suppose it’s possible that this was just your very, very misguided attempt to say “No apology necessary”. If so, you desperately need to learn English.

    Because what you’ve told me so far is that I didn’t mean my apology, viz:

    Don’t apologize unless it means something.

    And that my apology is meaningless, viz:

    How could your apologies have meant anything?

    And finally you told me that you know better than I do whether I should be apologizing at all, and in your opinion I’m making a mistake.

    Thanks a heap, it’s been a pleasure apologizing to you …

    Now, maybe your intention was totally benign here … and if so, is English your third language or something? Because telling a man that his apologies are meaningless, and that he shouldn’t apologize unless he means it, and that you know better than he whether he should apologize at all … well, on my planet that is a damn strange way to respond benignly to an apology.

    But if that’s the case, if your intentions were in fact benign, then my advice is that when a man apologizes to you, you button your smart lip, you forget circumlocutions and fancy phrases, and you just say thanks, apology accepted.

    Because whether you think I need to apologize is simply interference. Your job is to STFU and accept the apology without comment, because obviously I think I need to apologize.

    Finally, it’s never easy for a man to apologize, at least it’s not easy for me to do so. As a result, when dealing with someone who is ill at ease and edgy already because he’s screwed up and is apologizing, it’s definitely not a time to be joking around or to be practicing your English. You want to avoid misunderstandings, it’s not a time to get smart.

    It’s a time to say “I appreciate and accept your apology” and move on.

    I’m gonna assume you didn’t know better and move on myself, my blood pressure’s back down. I just gotta remember some people never did learn manners …

    w.

  46. atheok says:

    “…It’s also strangely reinforced the many warnings of the farming relatives to avoid goats altogether when I asked. Which was saddening, as the TV had led me to believe a few of the small ones would be excellent self-directed self-refueling combination lawnmowers/weed-whackers. I likely wouldn’t have had to even fence or pen them in either since, well, if those invisible fence and shock collar combos can contain a St. Bernard or pit bull…”

    Um…
    Not that my opinion or perspective is worth much. a friend of mine bought goats under the same premise. They love the goats, in a way, and the goats are extremely effective.

    Everything green from cut grass level, (actually darn short) to about seven feet high is trimmed; with very few exceptions. How the goats manage to stretch seven feet up to trim branches is puzzling, but if it is chewable, it’s graze to them.

    They ended up putting in a wire fence, not for the goats so much, but for dogs. Without an assertive ram, goats are harried, bitten and killed much like sheep are. The goats do get out occasionally but are caught quite near as they stop to browse at the first choice items.

    As far as the electronic methods; I don’t know nor do my friends though they did consider the option. The roaming dogs made their minds up for them.

    Yes, your style; even in your response to me, you are methodical, replied in even steps with continuity. Your message was fairly clear and I didn’t think to myself, “What?” while reading through a sentence or paragraph. No slight is intended. Instead, I’d press my commentary as complimentary to your writing.

    Official sarcasm html support would be great. Then even words and imbedded sentences could be so identified. Maybe when the next version is released.

    “Lesley McKay says:
    March 6, 2013 at 8:36 pm
    kadaka
    let it be mate, you are over egging it”

    Excellent advice for me too Lesley! Thanks for the friendly reminder.

  47. James Allison says:

    kadaka (KD Knoebel) says:
    March 6, 2013 at 4:18 pm

    A fun and well written spoof Kadaka – I recognise the skill, thank you.

    Willis is either a wound up personality, tight, like a spring – as you suggest – which slights the ebb and flood flows of his incessant pacific stories. Or perhaps he’s simply gotten too enthralled in his own cleverness to see the lightness around him. Willis I recommend the old Czech movie “The unbearable lightness of being”

    All the best
    J

  48. johnmarshall says:

    Dr Tim Ball:- quite right 60N-60S is hardly global.
    I lost a little respect for Dr Spencer when he told me that the 2nd law of thermodynamics could be violated.

  49. kadaka (KD Knoebel) says:

    Re Willis Eschenbach on March 7, 2013 at 12:06 am:

    So let’s just agree, if we were in the same physical location, to each have their beverage of choice and laugh the whole thing off, put it behind us, life’s too short.

    Deal?

  50. Willis Eschenbach says:

    kadaka (KD Knoebel) says:
    March 7, 2013 at 4:08 am

    Re Willis Eschenbach on March 7, 2013 at 12:06 am:

    So let’s just agree, if we were in the same physical location, to each have their beverage of choice and laugh the whole thing off, put it behind us, life’s too short.

    Deal?

    Deal anytime, my friend. Totally seriously, let’s have a good laugh. I’m buying …

    James Allison says:
    March 7, 2013 at 1:21 am

    kadaka (KD Knoebel) says:
    March 6, 2013 at 4:18 pm

    A fun and well written spoof Kadaka – I recognise the skill, thank you.

    Willis is either a wound up personality, tight, like a spring – as you suggest – which slights the ebb and flood flows of his incessant pacific stories. Or perhaps he’s simply gotten too enthralled in his own cleverness to see the lightness around him. Willis I recommend the old Czech movie “The unbearable lightness of being”

    “Spoof”?

    Listen, James, when a man is apologizing to you, the idea that you should “spoof” him is pathological.

    Kadaka got into trouble the first time by being too foolish to put in a “sarc” tag. Yes, I was “spoofed”, and it damn near cost kadaka my friendship. Great joke, right?

    You seem to think that taunting or spoofing a bear is funny. Heck, bear-baiting used to be a sport in England, you were just born too late.

    James, I get attacked by ambulatory rectums every day of the week, who at present are totally indistinguishable from you. Yeah, go ahead, see if you can spoof me into thinking you’re one of them, that will be great fun …

    I can assure you. The bear doesn’t see the joke, and it might cost you dearly. You’ve already lost stature on my planet, at this point your opinion is valued right up there with my dog’s opinion … and I don’t have a dog.

    Ha ha ha, yeah, James, that spoof was damn hilarious, nothing like poking a man with a stick, and then when he jumps, tell him he’s wound too tight … you’ll make a friend for life that way.

    James Allison.

    No question … I’ll remember that name …

    w.

  51. Willis Eschenbach says:

    johnmarshall says:
    March 7, 2013 at 2:23 am

    Dr Tim Ball:- quite right 60N-60S is hardly global.

    Yes, and Willis Eschenbach:- quite right … it makes no practical difference regarding this question. Once again …

    w.

  52. GeoLurking says:

    kadaka (KD Knoebel) says:
    March 6, 2013 at 4:18 pm

    … I likely wouldn’t have had to even fence or pen them in either since, well, if those invisible fence and shock collar combos can contain a St. Bernard or pit bull…

    Dunno how reliable that would be. I overheard two corrections officers discussing on of their charges that had a tendency to strip off his clothes and leap onto the electric fencing. Ostensibly for the sheer entertainment value.

    The story is real, whether they were being factual with each other is debatable.

  53. James Allison says:

    Willis Eschenbach says:
    March 7, 2013 at 9:38 am

    Nice thought you wanting to remember me Willis but I real can’t fit your ego into my life.

    All the best

    J

  54. Willis Eschenbach says:

    James Allison says:
    March 7, 2013 at 10:41 pm

    Willis Eschenbach says:
    March 7, 2013 at 9:38 am

    Nice thought you wanting to remember me Willis but I real can’t fit your ego into my life.

    All the best

    J

    I do love these tragic announcements about how someone is going to take their ball and go home, and it’s supposed to be this heavy thing, them depriving us of their priceless company and witty repartee. But they have to do it, you see … because I’m so unbearably bad.

    Me?

    James, you are the one who thought it was some kind of fun joke to “spoof” me. You are the one who thought it was great when KD poked the bear with a stick, and now that the bear bit your hand bit off as well, somehow you’re the noble guy and the problem is the bear’s ego is too big?

    Really? That’s your excuse for your pathetic behavior, the bear’s ego?

    And yet despite the fact that you can’t stand me, here you are, still barking at my ankles and disturbing respectable people, another man once again threatening to leave … but who hasn’t left quite gotten up the courage to leave yet, it’s dark outside, and besides, you gotta get in one more bark.

    If you want to go, James, then why are you still here? Don’t stand on the order of your going. Don’t bother with final farewells, they just make you look operatic and ridiculous. Nobody cares if you leave, this is the internet. Someone equally unpleasant will show up soon, you won’t be missed.

    Now, please be clear about my position in this, which is that you’re more than welcome to stay. If you want to go that’s your choice. If you stay and can get over your upset, you might learn something.

    So the choice is yours, but if you go away, don’t go away mad, it’s hard on your liver … just go away. And if you stay … don’t stay mad either. Just remember your lesson about interfering when two men have a disagreement and a misunderstanding—if you want to take a hand in that kind of circus, the bear may bite it off …

    Regards …

    w.

  55. Gras Albert says:

    more soylent green!

    Does anybody have an overlay that shows sea surface temperature and HadCRUT, GissTemp, and others? I’d like to see how the data compares over time.

    NIck Stokes

    Here is one. You can add or remove data as you wish.

    Sorry, link got messed there. Hope this works

    MSG, it’s amazing what Nick’s tool can show

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