Arguments
Lindzen's Junk Science
Posted on 8 March 2012 by dana1981
This is a re-post from Gavin Schmidt at RealClimate regarding another Lindzen misrepresentation in the seminar discussed in Lindzen's London Illusions. As noted by Skeptical Science reader WheelsOC, the graphic in question used by Lindzen in his London presentation appears to have been created by Howard Hayden and posted on Junk Science. This suggests that the error discussed by Schmidt was actually made by Hayden and then uncritically reproduced by Lindzen (who also did not provide a reference citation for the faulty graphic in his presentation).
Richard Lindzen is a very special character in the climate debate – very smart, high profile, and with a solid background in atmospheric dynamics. He has, in times past, raised interesting critiques of the mainstream science. None of them, however, have stood the test of time – but exploring the issues was useful. More recently though, and especially in his more public outings, he spends most of his time misrepresenting the science and is a master at leading people to believe things that are not true without him ever saying them explicitly.
However, in his latest excursion at a briefing at the House of Commons in the UK, among the standard Lindzen arguments was the following slide (which appears to be a new addition):
What Lindzen is purporting to do is to compare the NASA GISS temperature product from 2012 to the version in 2008 (i.e. the y-axis is the supposedly the difference between what GISS estimated the anomaly to be in 2012 relative to 2008). A rising trend would imply that temperatures in more recent years had been preferentially enhanced in the 2012 product. The claim being made is that NASA GISS has ‘manipulated’ (in a bad way) the data in order to produce an increasing trend of global mean temperature anomalies (to the tune of 0.14ºC/Century compared to the overall trend of 0.8ºC/Century) between the 2008 and 2012 versions of the data, which are apparently shown subtracted from each other in Lindzen’s figure. Apparently, this got ‘a big laugh’ at his presentation.
However, this is not in the least bit true: the data are not what he claims, the interpretation is wrong, and the insinuations are spurious.
The annotation indicates that Lindzen is using the GISTEMP Land-Ocean Temperature index (LOTI, i.e. the index that includes weather station data and sea surface temperature data to give a global anomaly index with wide spatial coverage) (“GLB.Ts+dSST.txt”). There is another GISTEMP index (the Met station index) which only uses weather station data (“GLB.Ts.txt”) which doesn’t have as much coverage and has a substantially larger trend reflecting the relative predominance of faster-warming continental data in the average.
Old versions of the data can be retrieved from the wayback machine quite readily, for instance, from February 2006, October 2008 or December 2007. The current version is here. I plot these four versions and their differences below:
As should be clear, the differences are tiny, and mostly reflect slightly more data in the earlier years in the latest data and the different homogenisation in GHCN v3 compared to GHCN v2 (which was used up to Dec 2011). This is however in clear contradiction with Lindzen – the biggest difference in trend (between 2006 and today), is a mere 0.05ºC/Century, and from 2008 to 2012 it is only 0.003ºC/Century – a factor of 40 smaller than Lindzen’s claim. What is going on?
The clue is that the transient behaviour of Lindzen’s points actually resembles the time evolution of temperature itself – not homogenisation issues, or instrumental or coverage changes. Indeed, if one plots the two GISTEMP indices and their difference (using current data), you get this:
Thus it looks very much like Lindzen has plotted the difference between the current Met Station index and an earlier version of the LOTI index. I plotted the Feb 2012 Met index data minus the Feb 2009 LOTI index, and I get something very close to Lindzen’s figure (though it isn’t exact):
This is sufficient to conclude that Lindzen did indeed make the mistake of confusing his temperature indices, though a more accurate replication would need some playing around since the exact data that Lindzen used is obscure.
Thus, instead of correctly attributing the difference to the different methods and source data, he has jumped to the conclusion that GISS is manipulating the data inappropriately. At the very minimum, this is extremely careless, and given the gravity of the insinuation, seriously irresponsible. There are indeed issues with producing climate data records going back in time, but nothing here is remotely relevant to the actual issues.
Such a cavalier attitude to analysing and presenting data probably has some lessons for how seriously one should take Lindzen’s comments. I anticipate with interest Lindzen’s corrections of this in future presentations and his apology for misleading his audience last month.
Instead, he's stuck presenting junk science such as documented here (or in the London Illusions post) to political figures and, for lack of a better term, celebrities, with political, ideological or financial interests in preventing effective policy action to avert warming.
Historical records are revised whenever new data or errors of interpretation are uncovered (ask the guys at UAH about a career in it). Lintzen should accuse Spencer and Roy of the same thing.
The U.S. Government just cancelled a NOAA project to do a detailed reconstruction of American weather conditions for the entire 20th century. That certainly would have revised the ddata sets, and by extension the global data sets.
There is a current blog-buzz over apparent temperature adjustments to Icelandic data - without consulting the meteorologists in Reykjavik. Lintzen is no better than the blogs.
The MET is coming out with a 'new and improved' HadCrut4. Ricky MIT might want to leave England before he smears that one.
Lintzen, beyond whatever data-selection errors he may or may not have had, is playing the Janus when he points at inaccurate or insufficient data, and then cries 'fix' when the dataset is upgraded.
He's jumped the shark on this one.
Your excellent Escalator graph seems to have a small bug: in the 'Skeptical' version the temperature drops completely at the right end of the graph (but without a point??). I know we have had some 'flattening' over the last decade, but we didn't drop to the 1973 value, did we? Also in the 'Realist' version I don't see the drop.
P.S. Of course if the value really occurred, we should include it!
There is no bug. The "skeptical" (==ignorant or willfuly misleading) version draws from incomplete 2011 data and goes out of whack. The realist version draws from complete data.
It is explained in this thread:
http://www.skepticalscience.com/going-down-the-up-escalator-part-2.html
Thank you for your explanation. However I do not see any mention of the weird end point in the link you give; only the general mechanism is given (which is of course perfectly obvious to anybody unbiased).
It may be good to explain the weird end point explicitly, because a small thing like that is used by the denialists to cast doubt on the whole graph.
PS If I overlooked something, apologies.
Dana's very busy at the moment, but maybe he'll update the animation in the coming months.
It's certainly possible that Hayden simply clicked the wrong data set in one instance, but Lindzen should have known better than to uncritically accept a plot posted on Junk Science (or wherever he got it) which accuses other scientists of data manipulation without verifying its accuracy.
Thanks for keeping us educators informed, Skeptical Science folks.
Hanson has been giving a talk at TED2012 and it is well worth watching, especially by those who are still in doubt about Climate Change. He not only talks from the heart, but as we on this side of the fence are fully aware, he actually knows what he is talking about. Perhaps a better description would be that he is the exact opposite of Monckton.
Thanks for clearing this up guys. I appreciate it.
"Note that I have received a note from Lindzen apologising for the error (and I have passed it along to the people involved in GISTEMP). - gavin"
My compliments to Dr. Lindzen for this - not everyone is willing to acknowledge an error.
Great that you posted this - the myth will likely have legs among the pollutionist blogs, so it's nice to have a flyswatter response.
Could you list them?
When I last checked, the Repeal the Act ePetition had just over 1000 signatures so they are never going to change policy that way (100k required to trigger Debate) but what is more concerning is Monckton's claim that Lindzen was whisked away afterward to brief a Cabinet Minister. This is clear interference in UK politcs and I would love to know what MIT think about it.