Many readers are familiar with the Central England Temperature Record (CET), now Frank Lansner investigates the Central Netherlands Temperature Record (CNT). Long, but enlightening. – Anthony
Guest post by Frank Lansner
Instead the KNMI has decided only to make available their “CNT”, the Central Netherland Temperature index.
KNMI do make two coastal temperature series available before 1951 (Vlissingen and De Kooy) and then some strongly adjusted temperature series (De Bilt and Maastricht). Finally the Northern Eelde Station that has not been adjusted has been made publically available, fortunately.
To make the “CNT”, KNMI use strongly adjusted versions of their temperature data, let’s start out with Maastricht:
Fig2
Before 1950 close to one full Kelvin of heat has been taken out of data. The strong dive in temperature 1950 has been removed.
Fig3.
Exactly the same occurs for the De Bilt station, the temperature dive in 1950 has been removed.
Fig4
Here the combined adjustments of Maastricht and De Bilt data. The “Central Netherlands Temperature” index is shown here too. It is almost identical to the adjusted De Bilt and Maastricht data.
Fig5.
The raw temperature data from Bruxelles station Uccle obviously confirms the raw versions of De Bilt and Maastricht. Perhaps slightly more urban heat warm trend can be spotted in the Uccle data. But check this:
Fig6.
It does seem that the other Bruxelles station “Bruxelles National” has less warm trend than the Uccle station, suggesting a little UHI in the Uccle dataset?
Fig7.
Let’s move on, the Luxemburg station is available from Crutem3, and the dive in temperature from the late 1940´ies to 1956 yet again is confirmed.
Imagine that KNMI was correct in their adjustments and just by coincidence we have De Bilt, Maastricht, Uccle and Luxemburg showing a HUGE freak error simultaneously in 1950.
Would it take a miracle at this point for KNMI to be correct?
Well, let’s move on.
Fig8.
From GHCN we have Frankfurt-Wiesbaden temperature data again the warmer pre-1950 data are confirmed. In addition the warm peak 1957-62 is stronger in central Germany.
In my previous article on this matter I analysed a row of German stations from raw GHCN V2, check link in the end of the article.
Fig9.
On the site “Tutiempo” you can normally find adjusted data but I checked out this “Ypenburg” station. It appears that in the period approx. 1936-55 there was an Airport in Den Haag called Ypenburg. Tutiempo for some reason holds just a little sequence of apparently raw data from Den Haag Airport:
Fig10.
The Ypenburg station is around 10 km from the coast. The “choice” of years available from Ypenburg is perfect: We have once again confirmed the large dive in temperatures 1949-1956 in Southern Holland.
How about Paris data? They must be available? For some reason NO raw temperature data is available before 1951 from all Northern France. But Paris then?
Fig11.
Obviously we should expect some UHI for a Paris station, but none the less, the Paris Orly data – (although not showing 1956) do confirm the warmer pre 1950 temperatures compared to the 1970-80 level. Also Paris do not support KNMI and their “CNT”.
Fig12.
When I first looked at Paris “raw” GHCN data I was surprised because the year 1949 showed a large temperature dive unlike the other stations in the area. However, the 1949-dive in GHCN Paris L Bourget was contradicted not only by all other stations in the area, but also by the other Paris dataset, Paris Orly, here taken from Tutiempo. Thus, all Northern French raw data are eliminated in GHCN before I 1951, and then the only dataset with a 1949 peak happens to have the data point lowered 2 K.
Fig13.
Before returning to the Netherlands, Finally one more German station from raw GHCN V2, Dresden (for more German and Czhech stations, see the link 2 in the end of the article).
Gemert:
Yet another Dutch temperature station seems to behave wrongly according to KNMI, and then the error happens to take place in 1950, so that KNMI have to lower the pre-1950 temperatures:
Fig14.
This is how KNMI illustrates the corrections done to the Gemert station. They compare to a reference dataset I believe is not public, but that is likely to resemble the CNT.
KNMI explains the changes to the Gemert station:
“
Gemert had a large break in October
1949, when the station was renovated. In the period 1906_
1949 the record shows a significant positive trend relative to
the reference stations Oudenbosch, De Bilt and Winterswijk.
This trend was likely to have been due to a gradual growth of
the vegetation at this station until the re-instalment in 1949
“
So, the increasing divergence 1906-1950 with (already adjusted!) De Bilt and more is due to plant growth, and the change 1949-50 is then due to re-instalment, KNMI says.
Fig 15.
Same scenario, this time its Uccle divergence from the KNMI “homogenized” De Bilt data set.
So the Uccle increase in divergence 1906-1950 to the “homogenized” KNMI De Bilt data is also plant growth then? And also a re-instalment in 1949-50 in Bruxelles, perhaps?
But the increase in divergence is even faster 1880-1906 – So plants grew even faster before 1906?
Fig 16. From figure 5 of [1].
1) Its definitely possible that I misunderstand this figure, but as I understand, it shows the divergence between individual stations and then a reference trend based on data from Netherlands? If so, how come al stations show a positive divergence 1940-50? Should a valid reference not be made so that it resembled actual temperatures of Netherlands as much as possible?
2) The Maastricht and De Bilt stations only differ from this reference with around 0,15 K.
As the difference between raw Maastricht/De Bilt versus CNT is around 10 times as much, this suggests that this figure actually show divergence between a reference and already ADJUSTED temperature sets. I’m not sure what scientific value this has.
3) The Eelde divergence is shown lower than the De Kooy divergence. As we will see later, Eelde is roughly 0,5K warmer than for De Kooy before 1950.
So how come they can show De Kooy with a warmer divergence than Eelde?
Again it seems that several data sets have been adjusted before showing divergences in the above illustration.
One more note: The illustration do not show data points for Leeuwarden 1949-55?
Fig17.
Many Tutiempo temperature series I have been able to test against raw data appear to be warm adjusted. But the point here of mentioning Leeuwarden none the less is that we from Tutiempo learn that this data set do exist at least from 1949.
So, why did KNMI only use data from 1955 in their illustration?
Eelde:
Fig18.
In Northern Holland we also have the KNMI data for Eelde and it can be proven unadjusted against NACD V1. Eelde data resembles Leeuwarden data from Tutiempo, and thus the Tutiempo Leeuwarden dataset also appear unadjusted.
In comparison with the previously shown apparently raw datasets, this Northern region with the Eelde and Leeuwarden stations appears to have had a slightly colder period 1930-50 but still around 0,5-0,6 K warmer than the “CNT”.
Coastal temperature stations of the Netherlands.
Fig19
When examining data we know is raw (or have a reason to believe is raw), then only the coastal stations Vlissingen and De Kooy show similarity with the “CNT” temperature trend before 1950.
CNT appear to be the “Coastal Netherlands Temperatures” rather than the “Central Netherlands temperatures”.
Fig20.
We can now estimate coastal and Non-coastal temperature trends for Benelux based on coastal stations De Kooy and Vlissingen and non-coastal stations Uccle, Luxemburg Airport, Eelde, Maastricht and De Bilt. All are raw datasets. Obviously stations Uccle and Maastricht are likely to include some urban heat.
Fig21.
NE USA coastal and Non-coastal temperature trends. Somewhat similar to the Benelux data sets. (taken from link 3: From RUTI Coastal temperature stations.)
Closing comment:
Yes, here and there I cannot be 100% sure which stations are adjusted and which are not.
The issue here is that raw data from KNMI is not just freely available, that would be a lot easier. But since this is not the case, I find it better to try to give the best estimate possible.
Bonus info.
Fig22.
The distance ocean air influence over land is illustrated her for SW Jutland [4]. Most of the ocean effect disappears just around 5 km from the coast (depending on topography also). Therefore the poorest stations to use for land temperature estimation are the coastal stations. However, many hundred kilometres from the coast, still the coastal trends can dominate temperatures on hills and mountains, and sometimes valley stations just downstream from larger mountains.
Links:
1 The creation of a Central Netherlands Temperature, KNMI:
www.knmi.nl/publications/fulltexts/CNT.pdf
2 NW Europe and De Bilt (more details on German stations from raw GHCN V2)
http://hidethedecline.eu/pages/ruti/europe/nw-europe-and-de-bilt.php
3 More on Coastal temperatures.
http://hidethedecline.eu/pages/ruti/coastal-temperature-stations.php
4
http://img.kb.dk/tidsskriftdk/pdf/gto/gto_0047-PDF/gto_0047_69738.pdf
If you have the time, please cut and paste the below temperature data while they are online…
http://www.tutiempo.net/en/Climate/Brize_Norton/36490.htm
http://www.tutiempo.net/en/Climate/Prestwick_Airport/31350.htm
http://www.tutiempo.net/en/Climate/Bremen/102240.htm
http://www.tutiempo.net/en/Climate/Hamburg-Fuhlsbuettel/101470.htm
http://www.tutiempo.net/en/Climate/Hannover/103380.htm
http://www.tutiempo.net/en/Climate/Nuernberg/107630.htm
http://www.tutiempo.net/en/Climate/Koeln_Bonn/105130.htm
http://www.tutiempo.net/en/Climate/Paris-Orly/71490.htm
http://www.tutiempo.net/en/Climate/Szczecin/122050.htm
http://www.tutiempo.net/en/Climate/Gdansk-Rebiechowo/121500.htm
http://www.tutiempo.net/en/Climate/Gdansk-Rebiechowo/121500.htm
http://www.tutiempo.net/en/Climate/Koebenhavn_Kastrup/61800.htm
http://www.tutiempo.net/en/Climate/Bruselas_Bruxelles_National/64510.htm
http://www.tutiempo.net/en/Climate/Leeuwarden/62700.htm
http://www.tutiempo.net/en/Climate/YPENBURG_NAFB/62000.htm
http://www.tutiempo.net/en/Climate/Guernsey_Airport/38940.htm
PLEASE GIVE ME A TIP IF YOU HAVE KNOWLEDGE ON
RAW TEMPERATURE DATA IN WRITINGS ANYWHERE IN THE WORLD
Pat @ur momisugly 7.35 and Myrhh @ur momisugly 11.50
Thanks for the updates on the UK weather this month. I recall a comment/thread in early April highlighting the major difference of forecasts foe weather in the UK for May. Piers Corban said it would be extremely cold ( comparatively for May ) and the UK Met office said it would relatively mild. So it looks like PC has shown up the Met Office ( with all its super computers and fancy models) has won their “little” difference of opinion. No wonder the bookies will not take bets from PC anymore.
The real issue with the adjustments isn’t whether they are justified or not. The problem is the opportunity they present to introduce confirmation bias, which is well documented in branches of science better known for their methodological rigour than climate science.
For quite a lot of data (36 stations), select starting date and stations:
http://www.knmi.nl/klimatologie/daggegevens/selectie.cgi
(Dutch only, English link broken)
Suffolk Boy
Thankyou very much for assistance. In my file from BEST it really looks like data where scrambled. In the header they write that this should be temperature but i got really dissapointed. Again..
If you have the 2011 version of best data, is there any chance that I can mail you the BEST station numbers that im interested to see, and then you can mail me the data?
I know its a lot to ask :-/
If so my mail: [SNIP: Frank, posting your e-mail address is not a good idea. I am forwarding your request to Suffolk Boy with your e-mail address. -REP]
K.R: Frank
Tonyb and Gail Combs: Thank you very much for your comments, and I think its extremelyinteresting with that Phil Jones quote you were discussing!
K.,R. Frank
Boels069
Thankyou for link to the daily Dutch temperature data.
But even in that context of 36 stations, they insist only to show pre-1951 data for the usual five:
De Kooy
De Bilt
Maastricht
Eelde
Vlissingen
In their own CNT-report they also use data pre 1951 from:
Groningen D006 H 19061951
Winterswijk D020 G 19061990 Nov 1944 De Bilt
Hoorn D029 G 19061990 Nov 1947Apr 1948 Den Helder
Oudenbosch D032 G 19061992
Gemert D033 G 19061990
Sittard D145 G 19061948 Apr-Aug 1940, Nov 1944-Feb 1945 Maastricht
Twenthe D146 G 19471970
And from other sources I know that pre-1951 data also exists in
Leeuwarden
Gilze-Rijen
Twenthe
Valkenburg
Ypenburg
And there are probably more. But these data appears to be a royal national secret.
Moderator: Than you so much for help!!
Frank
I sense “conspiracy” in your writings.
Have you vistited the met office library in De Bilt? Not everything that is published in print is put online, because somebody has to do the work.
In nearly every university library in The Netherlands you can find the publications of Aart Labrijn which contains all the data up to 1945 in print.
1 Labrijn, A. Het klimaat van Nederland gedurende de laatste twee en een halve eeuw. Schiedam, 1945. Proefschrift Utrecht [‘s-Gravenhage, 1945]. Mededelingen en Verhandelingen, KNMI, 49
2 Labrijn, A. Overzicht van de in Nederland met behulp van instrumenten verrichte weerkundige waarnemingen in de 18e en 19e eeuw. Hemel en Dampkring, 40, 1942, p. 19-21.
3 Labrijn, A. Overzicht van de in Nederland verrichte waarnemingen met behulp van instrumenten tot ± 1850. Hemel en Dampkring, 39, 1941, p. 20-24
RTFR
Some historic data (Dutch only):
http://knmi.nl/klimatologie/daggegevens/antieke_wrn/index.html
(Note the Labrijn-series from 1706 to present)
Hans Erren
I am fortunate to live near the Met office in Exeter who have an excellent library AND archive where there are very many interesting things. Most work has not been digitised and for many reseachers if it has not been digitised it does not exist and is not used. I was also at the Library of Exeter Cathedral last week looking at anything that might relate to the climate of the 14th and 15th Century. Nothing whatsoever from there is online and unlikely to be for years.
You never know what you might find in such places and they are worth investigating. Many interesting older books relating to climate HAVE been put on line but I suspect not many people read them unless they are ‘famous’
tonyb
Jongens,
jullie snappen het ook allemaal nog niet,
kijk naar de maxima
vergeet de rest
http://wattsupwiththat.com/2012/05/10/a-blast-from-the-past-james-hansen-on-the-global-warming-debate-from-13-years-ago/#comment-989111
Frank,
you can find a lot more data from Germany from the DWD site. They are constantly updating the timeseries. You can even find daily temperature data from Hohenpeissenberg beginning in 1781 and 8 more beginning before 1902. Quite a few start in ’36/’37 then some in ’47 and then in ’51.
Unfortunatly you can’t directly link to the site but go to http://www.dwd.de, click on the union jack for english language then up on ‘climate + environment’ -> left on ‘climatological data’ -> just to the right is now ‘climate data – online – free’ click on ‘more’ -> on the left ‘climatological data for Germany’ -> ‘…per measuring stations’ -> now you can look around at ‘daily values’, ‘monthly values’ or ‘data in standard format’. There is information available for each type. If you click on ‘stationsoverview’ you can see when the series begin, but you can not get the data from there, you have to go back to ‘daily values’…
It is one of the least user-friendly sites I know about, but there really is a lot of information available.
Joel Heinrich,
thank you very much for the tip, but sadly some series i have tested appears to be warm adjusted compared to earlier versions. As i recall they dont write clearly “adjusted” or “unadjusted” and thus one has no idea what material we have. There are other issues with this data that I will describe in the future,
K.R. Frank
Steven Mosher says:
May 17, 2012 at 7:13 pm
////////////////////////////////////////////
Steven
I would not think that your comment regarding corrections for altitude has much in it as far as the Netherlands is concerned since the Netherlands is rather flat. According to Wikipedia: .
“The Netherlands is a geographically low-lying country, with about 25% of its area and 21% of its population located below sea level,[9] and 50% of its land lying less than one metre above sea level.[10]”
Not much altitude variation. The Netherlands is also not a sprawling country (say unlike Chile or Norway) so I doubt that there is much in the [latitude] comment either.
you can do it right or do it wrong. your choice.
Suffolk boy
I managed to get the huge BEST file from 2011, and then im chopping it up to around 20 files so its just a little easier to work with!! It looks good now.
K.R. Frank
Frank, I have downloaded 14,527 “Average annual climate values” pages from TuTiempo. It is a challenge to convert data found in them to csv format, because it is real nasty convoluted html, but it will be done and be made available to all. I do not think climate data could be copyrighted in a sane world, especially not at this stage of the climate debate.
Absolutely Brilliant Péter Berényi, thank you.
There are unadjusted and strongly adjusted values in one big pile and this is the challenge with this material.
But several records here – even though often just a few years are made available before 1950 – are simply unique, you cant dig it up elsewhere.
Tip: Check Hannover for
a) Tutiempo
b) GHCN V2
c) DWD´s site.
What a joke..
Again, thank you so much I wil really look forward to see what you have got.
As it is now, its a very slow process to browse tutiempo.
K.R. Frank
Frank,
Take a look at Steve Goddard’s site he has some US graphs that tell the same story. Major changes to NH and US temp records in the 40-50’s time frame. This is criminal.
Hi Frank, I had to restart the download from TuTiempo with a wider scope, because it turned out they publish data for the U. S. of A. in a different structure (by states within country) than for the rest of the world. I am not sure I will not be banned from the site due to overuse before it is finished. If not, the additional benefit is that now daily resolution is also included, even if it makes the download huge and time consuming. Anyway, scripts for extraction of annual data are ready (rather ugly one liners). As soon as I have the download finished, I will upload stuff to some place and leave a link to it here, so check back please later.
It will be in tsv format, because some station names happen to contain commas.
For extraction of finer resolution (monthly or daily) data some more work is needed. I am not sure yet when could I get back to it.
The worst case scenario is that we will have only non-US data at annual resolution for some 9000+ weather stations. The rest of stations may have data for some months in several years, but never enough to calculate annual averages.
I gave some more thought to the copyright issue. I really think all climate data should be in the public domain by now, because actual policies are based on them, which imply either direct or indirect taxation (boosting prices by overregulation). Therefore if some dataset happen to be copyrighted, states participating in the IPCC process (especially the EU, US, Japan & China) have to be compelled by joint political action to pay for it to the owner(s) to have them in the public domain once and for all, then publish them on the web in a standard, easy-to-process format. The same goes for the entire scientific literature on “Climate Change”, including the source code and full documentation of all computational climate models referenced in IPCC reports.
This money would only be a tiny fraction of what’s currently thrown to the wind anyway.
“”””” Fig2
Before 1950 close to one full Kelvin of heat has been taken out of data. The strong dive in temperature 1950 has been removed. “””””
You have a small typo there Frank; that should be “one full Kelvin of heating”; not one full Kelvin of heat. Temperature (Kelvins) IS the correct measure of “heating”.
either way…as long as your results match those approved by the polit bureau.
Hi Peter, thankyou again (!)
You write: “The worst case scenario is that we will have only non-US data at annual resolution for some 9000+ weather stations. ”
This is fine because, US original data from GHCN V2 raw is rather well described. Except recent years (!)
Im very much looking forward to see your creation one fine day, super.
Mosher: You did not right or wrong: You just didnt.
Frank you can either adjust for lapse rates doing things the right way, and discover that the adjustment is small. Or you can ignore doing things the right way and claim it doesnt matter.
The latter is something Mann would do. You are in good company
Berenyi Peter says
….some 9000+ weather stations. The rest of stations may have data for some months in several years, but never enough to calculate annual averages…;
Henry says
You honestly don’t need so many stations.
I looked at 9 weather stations in South Africa and essentially I got the same result as what I obtained here:
http://www.letterdash.com/henryp/global-cooling-is-here
(now 45 stations, when looking at maxima!!)
Initially when I found missing data for certain months or if a month’s data was based on less than 15 days of data, I put in the longterm average of that month.I later found out that that was a mistake because weather patterns follow cycles.
Subsequently, if I found a month’s data missing or if I found that the average for a month was based on less than 15 days of that month’s data, I looked at the average temperatures of that month of the preceding- and following year, averaged these two figures, and in this way estimated the temperatures of that particular month’s missing data.
Note that instead of the means (average daily temp.data) I got more useful information from the maximum temperatures – which can be more directly related to the decline of the heat coming from the sun.
I now find the relationship for dropping maxima in degrees C per annum versus years past at
0.0455 ln (x) -0.1273 , r2= 0.997.
0= no cooling or warming = 16,4 years ago (calculated from 2011, means cooling started in 1994/5)
The frightening aspect, if this relationship holds true, is that maxima would now be dropping at about 0.2 degrees C per annum already.
Earth average temps. has been able to hide this from us because it stores energy in the oceans and in vegetation, also in hydrological cycles and in the weather. However, it seems from my tables for means and minima that this store may be running empty. So we might be in for a shock soon.
I predict this year will be year where we start to see average temps. dropping quite dramatically.
Nevertheless, average temps. is not a good parameter because it will give us the information that we need too late…..
We should be putting some alerts now, before it is too late.
Mosher, its so simple: In the climate debate the validity of adjusted temperature data is questioned.
IN-data for BEST are very afoten adjusted data. Therefore BEST is useless.
Your job should have been to challenge these data, obviously.
Frank Lansner says:
May 21, 2012 at 6:14 am
Mosher, its so simple: In the climate debate the validity of adjusted temperature data is questioned….
___________________________
Mosher’s job is to defend the adjusted data so do not expect him to ever move from that position.
As a lab scientist, adjusting data, ESPECIALLY adjusting data with no calibrations to back up the reason an adjustment is necessary is a really big NO NO. You just do not adjust data. As I said before you use error bars and foot notes with explanations.
Just for the intellectual exercise.
If the move to Stevenson screens introduced a known bias, the correct method would have been to run the old station along with the new Stevenson screen station for at least a year to determine the bias for that longitude and latitude and elevation and time of year.
I find it very difficult to believe the adjustment is the same whether you are in Alaska or Siberia at 3,000 ft elevation in the winter and in Israel at 100 ft elevation in the summer. I really doubt that the bias would be the same for two stations at the same longitude and latitude and elevation that are on opposite sides of a mountain range.
We have certainly seen enough raw temperature data to know that an observation based method for bias correction was never done for most stations. As in the Australian data, most of the measurements were rounded or truncated to the nearest degree. Anthony’s Surface Station Survey shows the stations generally do not meet the written standard.
As Jo Nova’s website states:
Therefore the older temperature data has error bars of at least 0.5 to 1 C minimum.
Error analysis: http://strata-sphere.com/blog/index.php/archives/11420
This kills the “Earth is Warming” manta because the “warming” is within the noise of the error bars.
Gail Combs, you write: “We have certainly seen enough raw temperature data to know that an observation based method for bias correction was never done for most stations. ”
Yes, and in the mean time another fish is in the net.
Dutch station Woensdrecht also appears adjusted arond 1 K 1949, here to series from the BEST archive:
http://www.klimadebat.dk/forum/vedhaeftninger/woensdrecht.gif