I was surprised by the shrill headlines from a British newspaper with the old fashioned name the Telegraph: “The fiddling with temperature data is the biggest science scandal ever”. So what is this all about?
The story makes serious allegations, however Victor Venema explains why the Telegraph got it wrong in Variable Variability, and makes the point that three hand-picked stations from Paraguay – out of thousands – hardly matters. He also shows the effect of post-processing on the global mean temperature: it reduces the global trend compared to raw data.
The story also sparked some discussion between colleagues at the Norwegian Meteorological Institute, where I work, as several of us know the scientist cited in the paper quite well. It would be completely out of character that he’d endorse the views expressed in the article, and this is also what he conveyed to us.
The records show that the recent high temperatures on Iceland are unprecedented, contrary to the main message from the Telegraph. And the evidence is not just in the temperature, but in a wide range of observations.
I like to look at the numbers myself, especially since the journalist responsible for the Telegraph story, Christopher Booker, bases some of his allegations on climate records with which I have some experience. Booker dismisses the data records and claims that
weather stations across much of the Arctic, between Canada (51 degrees W) and the heart of Siberia (87 degrees E). Again, in nearly every case, the same one-way adjustments have been made, to show warming up to 1 degree C or more higher than was indicated by the data that was actually recorded.
It is implied that such adjustments have been made to the Goddard Institute for Space Studies (GISS) data as well as the data from the National Climate Data Center (NCDC).
The purports about systematic one-way adjustments can easily be tested by comparing the trends in the GISS data with the independent North Atlantic Climate Data (NACD) or a more recent temperature analysis for Svalbard by Nordli et al. (2014).
It is straightforward to test Booker’s claim with open-source methods and data (see R-srcipt), and when we compare the independent Svalbard temperature from Nordli et al (2014) with GISS, we see that the GISS data has a smaller annual mean trend than the independent Norwegian data set for the same years (Figure 1).
But is Svalbard representative for the this part of the Arctic? We can repeat the exercise for the most important temperature records from this region, and it is clear that there is no one-way adjustment, as purported in the Telegraph (Figure 2). In other words, our inspection of the actual data shows that Booker’s claim is false.
Another question is why there are differences between the different data sets. The GISS data are mostly taken from raw world weather records that have not been subject to the same quality control and homogenisation as the NACD or the Svalbard temperature of Nordli et al (2014).
Homogenisation is needed to remove effects from non-climatic artifacts, such as a change in the formula over time for estimating monthly mean values. Other conditions may include relocation of the thermometer, urban encroachment, or replacement of the instruments. GISS uses the GHCN adjustments, rather than doing it itself, but the way the GHCN corrects for artifacts may be different to the local met services.
Booker also accuses GISS and NCDC of using
“the warming trends to estimate temperatures across the vast regions of the Earth where no measurements are taken”.
A bizzare claim, and one may wonder why it seems so natural for Booker to make associations with misconduct. George Monbiot, on the other hand, has referred to him as a charlatan bent on spreading misinformation. In any case, a person who writes such a misleading story shows little respect for his readers.
References
- . Nordli, R. Przybylak, A.E. Ogilvie, and K. Isaksen, "Long-term temperature trends and variability on Spitsbergen: the extended Svalbard Airport temperature series, 1898–2012", Polar Research, vol. 33, pp. 21349, 2014. http://dx.doi.org/10.3402/polar.v33.21349
Eli #96, I’m no defender of Euan and Roger – Euan banned me from his site after all – but DC interconnectors are one thing they do know about and have written about. Nevertheless, they described interconnectors recently as a threat to the integrity of the UK grid. This because in the very short periods in recent years when they were exporting electricity, UK demand was near peak – and we are according to Euan/Roger duty bound to keep exporting when the French need power even if it means blackouts on the UK grid.
Thanks Chris, you make the point I was aiming at with more excellent detail. But if I cite the military as a witness to reality, I am told by our ever-present unskeptical “skeptic” industry and its cohorts that the military should keep its head in the ground wrt climate, because that is “political” and not their business. I violently disagree, and you know I can carry on … and on … when my dander is up ;)
I included a youtube of Jeremy Jackson’s superb (but long) presentation on the ocean to the Navy at Annapolis, but didn’t provide context, so will repeat it here.
https://www.youtube.com/watch?v=TAtCQ7REXAc
If you are limited for time but want to take a looksee, just forward through and read the powerpoints which cover most of it, but do look at the atmosphere of extreme hospitality and friendly collaboration between that long-haired guy and the military spit and polish people attending. Lovely!
His material is a mite depressing, as he points out that the IPCC consistently understates the case and the problems don’t stop at 2100, a point I wish was made more often.
Now I apologize for putting this all here, when it belongs in the open thread, but one might say that evidence-based material is appropriate in the context of Booker’s distorted world view and promotion of false material.
In my earlier note (#28), I suggested that, at the very least, the D T. or S.T. should grant a right of reply to Booker’s article, and allow scientists who really know about this topic to put the record straight. Right out of left field, we then learned yesterday that the D.T’s respected political correspondent, Peter Oborne, was resigning from the D.T. because he believed that the paper’s executive board was suppressing stories – in this case, the row about HSBC and tax evasion – in order to maintain favour with major advertisers. Would it be scurrilous of me to suggest, even weakly, that we should be concerned whether articles about climate change and climate science are being treated in like manner? That stories broadly supporting the science are … erm, how shall I put this? … given a lower prominence than they might otherwise deserve, for similar reasons i.e. to maintain corporate advertising revenue? And if so, how many other newspapers are suffering from the same problem? Just can’t help wondering. Any thoughts, anyone?
Hmm, I notice that GISTEMP is out; last month was the warmest January since the very remarkable January of 2007, which chalked up an anomaly of 0.93 C. At 0.75 C, January 2014 becomes the second-warmest in the record, supplanting 2002 & 2003, which are now tied for the #3 spot at 0.71 C.
http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt
More on GW and the military (following on the discussion by susan and chris at 87, 88 and 100) from the mainstream-ish press: http://www.rollingstone.com/politics/news/the-pentagon-climate-change-how-climate-deniers-put-national-security-at-risk-20150212
“The Pentagon & Climate Change: How Deniers Put National Security at Risk:
The leaders of our armed forces know what’s coming next – but deniers in Congress are ignoring the warnings”
The Telegraph aint all bad, it’s opinion pages are just for sale (or just google Oborne today)
#106–Er, ah, “January of 2015“, of course…
Euan Mearns @102.
I think you visual examination of the graphic shown @52 is deficient if you then tell us “This chart shows that GISS temp 1880-1997 N and S hemispheres are the same.” Do you not think it odd that an authority on the subject, one of our hosts, says “As is easily seen, the hemispheric trends are not the same”? Are you happy that he completely contradicts your statament. I think you are not looking properly, not looking past all the annual wobbles.
So let’s do away with the wobbles and use 5-year rolling averages. Here is that comparison, GISS & BEST. Note the 1970-2000 trends for BEST NH & SH are greatly different and that they are also a good fit for GISS NH & SH. This 1970-2000 is the bit under analysis in Roger’s figure 4. Both GISS & BEST sing from the same hymn sheet. Roger’s figure 4 shows what is also shown in the homogenised data.
Your assertion that “In the N hemisphere homogenisation does not introduce bias” is entirely unsupported. GISS & BEST are indeed in better alignment in the NH. But do we know NH homogenisation has made little net adjustment? Roger’s analysis says so, but is it reliable? What we can say with some conviction is that the coverage of met stations is far better in the NH and that may well have a bearing on the matter of GISS & BEST being in good alignment in the NH.
The anomaly data I plot is as downloaded from BEST & NASA. In no way is it “designed to try and make BEST look the same as the other reconstructions” and I would thank you not to insinuate I would stoop to ‘designing’ deception.
So we are left with a question as to whether Roger’s analysis could be right in showing the net homgenisation adjustments are mainly found in the SH.
The BEST website provides raw and adjusted data for individual met stations and also average adjusted and averaged temperature anomalies for largish lumps of land area (eg – data available here for about a third of SH Africa) and if I was interested in pursuing Roger’s claim, I’d be over the BEST website like a rash. Either that or go cap-in-hand to somebody who may be willing to produce the data from an existing data engine.
There is also the question of why does the resulting net homogenisation adjustments on a global scale take the form it does. Is it some systemic reason, as per the SST adjustments? Or is it more a random outcome?
#102, Euan Mearns – Try the CMIP5 mean hemispherical land-only data from 1880-1997 and 1880-2014. Calculating hemispherical trend ratios I get:
1880-1997 ratio = 1.04
1880-2014 ratio = 1.16
The pattern is very similar to that seen in the GISS data. This time-dependency is an expected feature, mainly due to declining hemispherical bias in cooling aerosol influence since about 1990.
BEST-land also indicates the same pattern:
1880-1997 ratio = 1.04
1880-2014 ratio = 1.24
Nick O.:
My thoughts are that it’s hardly scurrilous, it’s just kind of futile because so many already believe it. That belief is readily exploited by AGW-deniers, with tu quoque accusations that the mainstream media have a pecuniary motive to suppress their side — an argument that may be superficially plausible to the uninformed. RC regulars know all this, but they also know the propaganda war is an asymmetric struggle. Fossil-fuel billionaires can afford to protect their investments by hiring the most skillful professional disinformers. Lacking the profit motive, realists will always be outbid. Or so it appears to me.
#107–IMO, this paragraph speaks volumes about effective climate communication:
>Mearns … hemispheric trends … since 1997
You have missed much of the basic science and you can’t understand the complicated part without the elementary information from the beginning.
If you want to ask smarter questions, re-read Spencer Weart’s book.
For any kid brand new to the subject, the trick about his question is:
At some point in time, the global warming signal emerges from the noise.
You know from reading that the effect of adding CO2 is relatively a small effect, a weak signal, slowly adding up, compared to the other forces acting on the climate — but adding CO2 means always pushing the climate in the same direction. That’s what’s different from the other forces acting on the climate, which have their ups and downs over time.
It’s like a little drip into a big pot, which gets fuller over time.
Do you know when that signal emerges from the background variation? This takes basic statistics 101 or the willingness to trust math teachers. If you have that, you can look this stuff up.
LMGTFY
Satisfied yet?
Euan has another post on homogenization today (20.Feb), along with the usual gratuitous accusation of lies and fraud from one of his most prolific commenters. And Eaun does little to control his favored commenters’ insinuations and accusations.
The glaciers and sea ice are visibly waning. This melting requires a huge amount of energy. From where?
114 Hank Roberts: At some point in time, the global warming signal emerges from the noise. – See more at: https://www.realclimate.org/index.php/archives/2015/02/noise-on-the-telegraph/comment-page-3/#comments
You might appreciate this paper: The Annals of Applied Statistics
2014, Vol. 8, No. 3, 1372–1394
DOI: 10.1214/14-AOAS753
© Institute of Mathematical Statistics, 2014
CHANGE POINTS AND TEMPORAL DEPENDENCE IN
RECONSTRUCTIONS OF ANNUAL TEMPERATURE:
DID EUROPE EXPERIENCE A LITTLE ICE AGE?
BY MORGAN KELLY AND CORMAC Ó GRÁDA
University College Dublin
We analyze the timing and extent of Northern European temperature falls during the Little Ice Age, using standard temperature reconstructions. However, we can find little evidence of temporal dependence or structural breaks in European weather before the twentieth century. Instead, European weather between the fifteenth and nineteenth centuries resembles uncorrelated draws from a distribution with a constant mean (although there are occasional decades of markedly lower summer temperature) and variance, with the same behavior holding more tentatively back to the twelfth century. Our results suggest that observed conditions during the Little Ice Age in Northern Europe are consistent with random climate variability. The existing consensus about apparent cold conditions may stem in part from a Slutsky effect, where smoothing data gives the spurious appearance of irregular oscillations when the underlying time series is white noise.
Like most people of most persuasions, I thought that the Booker article was awful, and the accusation of dishonesty completely unfounded. There was a long discussion on this topic over at Climate Etc. I only mention this because I write skeptically about claims of extreme effects of CO2, and I prefer not to be associated with opinions like Booker’s.
#104 Susan Anderson said …but do look at the atmosphere of extreme hospitality and friendly collaboration between that long-haired guy and the military spit and polish people attending. Lovely!
You mean besides the first questioner who clearly is in the denial column and thanked Jeremy for his “opinion” climate change is confirmed at a similar level to a scientific law?
That’s the kind of polite I have no patience for. If you’re going to call someone a liar have the backbone to do it honestly. The implication of his questions was bad enough, but his “opinion” comment was extremely rude and patronizing. One is a well-known climate scientist and one is not.
Educable albeit ignorant, or beyond hope?
William @155.
With no sign of Euan Mearns here presenting further argument to support his crazy beliefs, I think it is safe to say he is back home on his blog, in his comfort zone, off picking cherries with the fairies. This is all the more strange given Euan tells us @55 that he has chum Roger Andrew’s analysis of 900 stations. I note Euan’s latest blog-post (22 Jan) is concentrating on mid-Australia and has managed to create a graph of raw temperature data with zero warming since 1907. And the first comment on the comment thread is from Roger Andrews who for some reason is showing the non-flat Australian temperatures according to BEST which Roger tells the world is down to the anomaly bases being different, apparently.
The argument brought here by Euan included the finding of Roger that all the GHCN adjustment resulted from the southern hemisohere. This hasn’t been tested in any way here, so far. I did think to compare a GHCN(Raw-Adjusted) plot with BEST-GISS(land) plot, and specifically BEST-GISS(NH) and BEST-GISS(SH). If there was any truth in Euan’s claim that BEST has got it right while GISS using GHCN has got it wrong, there should be a similar trend globally. And if it was down only to the SH, the BEST-GISS(NH) would be flat, and BEST-GISS(SH) would be an amplified version of the global GHCN would trace. But, oh dear, that is not what we see. Indeed, pre-1930 BEST-GISS is pretty-much featureless. :-)Could that be down to the anomaly base being different?
Cap and trade has been around for 25 years so why is our pollution getting so much worse so fast? Is it because it is easier now to buy rights from countries that pollute very little and in the process actually cause more pollution.
As an English journalist (I can still take a shorthand note of a conversation and transcribe the squiggles, 30 years after my course) may I defend The Daily Telegraph, if not Mr. Booker? The Telegraph was for many years the newspaper of choice for journalists in that it was news-heavy and regarded as a good source of news, as long as you knew that it was essentially a conservative (British conservative) publication. In recent years it has fallen into new ownership and its quality has declined as good, old-school editors, subs and writers have left (that’s not unique to the D. Tel, old hacks are going the way of the Dodo everywhere). Mr Booker is not regarded as a great authority on this subject and is read with the same disposability as every other columnist; I make some of my monthly £s from writing columns but I don’t think they make a whit of difference.
Peter McG @122.
Your thought that Booker’s writings “make (not) a whit of difference” rather conflicts with my own experience. Not infrequently I see Booker being used as the source of bold denialist assertions on letter pages and have witnessed folk in very strong denial (the sort that would write such assertions in letters to letters’ editors) being quized about why they hold such views and Booker along with Rose of the Mail are pretty much top of the autority given.
This demonstrates that Booker is giving such folk the red meat they crave, but further down the spectrum Booker will also be reinforcing such aberrant beliefs, developing such aberrant beliefs and sowing doubt in the minds of those who find AGW and its consequences a difficult view to espouse.