Tom Karl’s Trends Are Wrong – At Least in Slide 21
Guest post by Bob Tisdale
A number of bloggers on the WattsUpWithThat thread “Tom Karl’s Senate Dog & Pony Show – it’s worse than we thought, again” noted the curious errors in the trend lines in Tom Karl’s presentation to Senate. The one that stood out for me was slide 21, presented here as Figure 1. It showed the global land surface temperature anomalies and linear trends for the new (Version 3) versus existing (Version 2) Global Historical Climatology Network (GHCN) dataset.
http://i48.tinypic.com/4j4c60.png
Figure 1
First Observation: The slide title states the data is monthly, but the data illustrated are annual averages. Figure 2 is a graph of monthly Global Land Surface Temperature anomalies presented by the NCDC from January 1900 to April 2010. Monthly global land surface temperature anomaly data should look like that, with lots of month-to-month variation.
http://i45.tinypic.com/5k3xjp.png
Figure 2
Second, there are two linear trends listed on the Karl slide. Version 2 is noted to have a linear trend of 0.83 deg C/Century, while Version 3 is claimed to have a linear trend of 0.91 deg C/Century. But the trend lines are nearly identical and they present linear trends of approximately 0.75 deg C/Century, Figure 3. The trend lines are erroneous or the values listed for the trends are wrong.
http://i49.tinypic.com/28iyyhk.png
Figure 3
Trend lines of 0.83 and 0.91 deg C/Century should be noticeably different, as shown in Figure 4.
http://i48.tinypic.com/346at1d.png
Figure 4
And for reference, the NCDC’s Monthly Global Land Surface Temperature anomaly data, Figure 5, has a linear trend of 0.78 deg C/Century.
http://i47.tinypic.com/142a1b4.png
Figure 5
And the the NCDC’s Annual Global Land Surface Temperature anomaly data, Figure 6, has a linear trend of 0.77 deg C/Century.
http://i45.tinypic.com/v4qvxl.png
Figure 6
Makes one wonder. If a simple comparison graph with linear trends is so error filled…
SOURCES
Tom Karl’s Powerpoint Presentation is available here:
ftp://ftp.ncdc.noaa.gov/pub/download/Global%20Warming%20is%20Unequivocal%20TKarl%20May%206.ppt
A full-sized copy of Slide 21 is here:
http://wattsupwiththat.files.wordpress.com/2010/05/karl_senate_2010_pg21.png
The NCDC Land surface temperature anomaly data is available through the KNMI Climate Explorer:
http://climexp.knmi.nl/selectfield_obs.cgi?someone@somewhere
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Dave N says:
May 19, 2010 at 9:43 pm
It’s the Karl Urban heat island effect:
Dave logic dictates that:
1. Karl Urban is a Kiwi (New Zealander).
2. New Zealands NIWA says their surface temps are all going up. (Ever since Lord of the Rings. WETA WORKSHOP -> Volcano -> HELLO!)
3. Therefore Karl Urban is increasing the worlds surface temps.
Easy fix. Put Karl in the ISS in orbit, let them cope with 1 degree per century,….thats AGW logic for you…
Its Incontraverta-Robusta-Equivocal-able.
Looks to be done in haste, cobbled together at the last moment.
But the real problem is long before the graph stage, and that would be the hand-picked stations.
.6C / Century is more like it, and the NCDC does not show the accepted lack of warming the past 10 years. Up to 15 years, according to Phil Jones (and his raw data sets agree), as UHI is not universal to all cities.
UHI may have an upper limit. Has anyone digging into the raw data sets come across this?
I think Im about sick of looking at this highly dubious graph. I feel physically ill each time I see it.
Can some one just cut to the chase and plot me out the graph since 1998 and then tell me what the slope of the temperature increase actually is at the moment, so I know just what Im supposed to be in a panic about. To add a some bells and whistles, how about superimposing the rise in CO2 on the same graph so we can get a handle on what we are actually talking about.
Mike says:
May 19, 2010 at 7:45 pm
It may be, or at least it was. Like I mentioned before, note the graph has 2 warm PDO phases and one cool, so it certainly should be going up. I’m fond of Akasofu’s hypothesis that the curve is from a periodic signal like the PDO and a straight line recovery from the Little Ice Age, so overall, things should be getting warmer.
Is is not evidence of anthropogenic warming. Are you concerned about AGW, non-AGW, or any warming at all? For that matter, are you concerned about cooling? I read today that an adult female gorilla and 3 or 4 baby gorillas have died in a cold weather outbreak in Rwanda. Over here, some 125 manatees died in Florida due to cold stress.
This analysis of temperatures is entirely wrong. He does not understand that during the century different temperature regimes have existed that cannot be thrown into the same pot and forced to become a single linear trend. Right off the bat, the recovery from the Little Ice Age took about a century and came to an end with World War Two. At that point there was a break in the curve and an almost horizontal, slight cooling trend set in. If you look at NOAA’s temperature curve that is in his slide show you will see it too. But NOAA shows also a warming trend that follows this horizontal segment, starting about 1977. This is Hansen’s warming but it does not exist because satellites see nothing but temperature oscillations during this period, up and down by half a degree, but no rise until 1998. These oscillations are quite real and are synchronized to the ENSO phases in the Pacific. Their mean lines up nicely with the horizontal temperature segment that started with World War II. This period ends with a discontinuous rise when the super El Nino of 1998 shows up. After it has come and gone a new El Nino warming begins to form. But this one rises 0.2 degrees above all the previous El Nino peaks and what is more, it refuses to come down when it is time for a La Nina to appear. As a result, we get a run of six warm years where temperature stays near what is usually an El Nino maximum. It ends with a La Nina cooling in 2008. I call it the twenty-first century high. None of this has anything to do with carbon dioxide greenhouse effect. The cause of the super El Nino was a storm surge that brought warm water to the head of the equatorial countercurrent near New Guinea. The countercurrent then carried it to South America where it ran ashore, spread out, and caused the symptoms of the super El Nino we observed. The twenty-first century high that followed was caused by warm water left over from the super El Nino. Presence of this warm water can be verified by SST records from the Eastern Equatorial Pacific. While the temperature during these six years was 0.3 degrees higher than the mean of the nineties the curve itself is flat and must be fitted to its own horizontal temperature segment. The appearance of the 2008 La Nina signifies that the oscillating temperatures of the eighties and nineties have returned. I expect the current El Nino to be followed by another La Nina that should start sometime later this year, to be followed by another El Nino and so on. They are part of the ENSO oscillation in the Pacific that has existed since the Isthmus of Panama rose from the sea. The upshot of all this is that since there was no warming in the eighties and nineties when Hansen said there was and since subsequent warming had nothing to do with CO2 we can say that anthropogenic global warming has never been observed.
AC of Adelaide says on May 19, 2010 at 10:16 pm
Since when have people in Adelaide become such pansies that they feel physically sick when they see a graph? I guess it’s good that I left in 2002.
Mike says:
May 19, 2010 at 7:45 pm
Linear regressions are done on the data, not by putting a ruler on a crude graph from a power point slide. But do notice all the slopes are up. The world is warming.
Oh yes, the data.
What is the probability of error in each measurement? That is crucial to know if you are going to start using statistics to pull the data apart. I can say blah blah blah about such and such, but what is the probability the data is right? Well, turns out you can just multiply the measurement’s probability of being incorrect together and come up with it.
If, and I am being generous, each measurement has ‘the standard’ LOS of alpha=.05, and the surface stations alone represent 1200 measurements, you have an incredible chance of being wrong. The proper way to determine your level of significance, or sigma as it it was once called by Lubos Motl, is to divide your desired level of significance by your number of replications. 2 measurements a day for 365 days a year times the number of places taking measurements would be your replications. So please, come back when you have data that has error margins that properly represents the .05 claimed by IPCC. As in .05/365*2*bs where bs=number of active climate stations. Then you have proved it to a 95% confidence level…
Oh puhleeze, as Anthony would say! Anyone who draws a straight line through these charts is deliberately, selectively blind. Try up, down, up instead. Response to more CO2 should be almost immediate as the atmosphere has little thermal inertia (unlike the ocean). These charts do NOT show what you would expect from more CO2. If you think that the warming is hiding in the oceans the heat flow can only to be from a warmer atmosphere into the oceans so the air temperatures has to show warming first. If the charts show anything, it’s that the slope is not due to CO2. Third rate ‘science’ from third rate ‘scientists’.
It’s either deliberate deception or a complete lack of quality control. Take your choice.
AlanG says:
May 19, 2010 at 10:49 pm
> Oh puhleeze, as Anthony would say! Anyone who draws a straight line through these charts is deliberately, selectively blind. Try up, down, up instead.
Umm, keep in mind the target audience were congresscritters. They can’t handle up, down, up.
rbateman says:
May 19, 2010 at 10:08 pm
UHI may have an upper limit. Has anyone digging into the raw data sets come across this?
Well, paritally and loosely. You have to go back to Dr. Spencer’s analysis on UHI and some ten thousand stations, the temperature vs. population density a few months ago. I believe it was his last chart of that series of articles which showed the logrithmic curve which implies that UHI will only continue to rise as a log of the population density. So if not viewed as a logrithmic chart it does appear to have an approaching upper limit.
That was a very good series on UHI by Roy. If you take the time to take his four data poins which represent a large number of station pairs and plot them in a logrithmic chart you will see something amazing. It’s a straigt line crossing the y axis between 0.2°C/cy & 0.3C/cy at zero population density. That’s impressive. Impressive in that it so closely parallels the sea temperature rise.
Richard Sharpe says: ……
May 19, 2010 at 10:41 pm
Guess I must be a pansy. And I soil my pants every time I see a “hockey stick” Guess when it comes to graphs I expect a bit of quality control. I’d leave here too if I could only find a place where they only print credible graphs.
Fitzy you are a kiwi too nice to meetcha
Thomas well said
1 degree warming per century since the LIA why are the Team getting their tits in such a tangle over this. Yes yes I know continued Government funding. Making their mark. Opportunity to publish papers in readily accetable journals blah blah. Thing that hits me is that nobody I talk to actually cares beyond their lifestyle and mortgages. Not withstanding this I commend WUWT and really appreciate Anthony and his millions of intelligent supporters that blog here and question the team. That includes you Mike who questions the questions.
I thought it used to be 0.6K per century in the IPCC report. How does it get to 0.9K per century when the anomalies have been static for over a decade? Is this the same bunch that calculate the unemployment statistics?
Gentleman,
For me, at least, this image (Figure 4) did not appear: even after several refreshes:
http://i48.tinypic.com/346at1d.png
[It came right up on my screen: “Confirms that global warming is robust.” ~dbs]
0.75 instead of 0.83!
Off with his head!
And we were lucky to have Mount Pinatubo in 1991.
We could have been 1.5 degrees warmer now than in 1900.
On the other hand you could say there hasn’t been no warming from 1990 to 2009.
I could also say there hasn’t been warming from 1900 – 1990.
And I could go on and on….
Explain the forcings that caused this temperature walk: http://rankexploits.com/musings/wp-content/uploads/2010/04/global.png
“snip” the “trendlines”.
Phillip Bratby says:
May 19, 2010 at 10:51 pm
“It’s either deliberate deception or a complete lack of quality control. Take your choice.”
Its both.
Next they will have a presentation on the economy and show the Dow Jones from 2002 to 2007. Then we can all rest assured that everything is AOK.
Basil says: “I have a problem with Figure 4. Linear trends go through the point of means.”
Figure 4 was presented as an example to show that the differenes between the trends of 0.83 and 0.91 deg C/century would be visible.
Mike says:
May 19, 2010 at 7:45 pm
Linear regressions are done on the data, not by putting a ruler on a crude graph from a power point slide. But do notice all the slopes are up. The world is warming.
Oh? Go to the Number Watch website & look up Chartmanship. It’s all about start points, end points, vertical & horizontal scaling, suppressing the zero, etc. It’s all good fun this statistics game, is it not? Puter says yeah!
Mike G wrote: “Not true. All the corrections for the first half of the 20th century were down.”
And when the corrections cause lower temperatures in the first part of the graph, the trend increases.
Ric Werme: You wrote, “Like I mentioned before, note the graph has 2 warm PDO phases and one cool, so it certainly should be going up.”
Ric, through what process would the PDO warm and cool global temperatures? Refer to:
http://bobtisdale.blogspot.com/2009/04/misunderstandings-about-pdo-revised.html
And:
http://bobtisdale.blogspot.com/2009/05/revisiting-misunderstandings-about-pdo.html
Is there similar data/graphs for any other planets?