Data from the 20 UK CLIMAT meteorological stations

Posted: October 9, 2012 by tchannon in Analysis, data, Dataset, Surfacestation

A WMO resolution requires release of some climatic data in the form of CLIMAT data messages. For the UK there are 20 stations, few given the land area. Most are from aerodromes, all are synoptic stations which have already been briefly covered as part of the surfacestation project.

I’ve obtained and decoded the raw data into .csv files intended for spreadsheet import.

[Important update]

[update 9th Oct. I’ve now found what looks like the formal WMO CLIMATE document

Search on this http://www.wmo.int/gsearch/gresults_en.html?q=climat&submit.x=0&submit.y=0

Points to “Handbook on  CLIMAT and CLIMAT TEMP Reporting (2009 edition), WMO/TD-No. 1188

/update]

Runs from at earliest 1996, to date. Is fundamentally monthly.

A first for the Talkshop, in a zip here.

Not everything is decoded but if anything useful is omitted, discuss. Eg. no wind data, monthly is of limited use. Decoded via a script which I had to write, pretty much automatic now.

I’ve included latitude and longitude complete with ready to use Bing and Google links for a web browser. (whether a spreadsheet will allow this, ah, could copy it)

Possibily of particular interest is inclusion of month min and max figures with date, unless it is tie, in which case the date is for the first instance.

I’ve barely looked at the data myself

One I have examined is Manston, Kent about which a part 2 post is mostly prepared. (have lots not published).
This station moved from human read min/max in 2000, apparently no bridging to AWS but a bit of mystery exists, may have been as many as four different sites until the present one.

There isn’t enough data to be clear on change min/max to AWS, at least I prefer obvious effects, not statistic, but it looks likely there is 4C under some conditions, I assume because the old site was poor. Got the location.

Very interestingly the hottest day was 10th August 2003, an infamous case of many records… but herein starts a tale.

Brogdale, also in Kent, 33km away is accepted as 3.9C hotter than Manston. I don’t buy this as sensible for competent sites. I still have reservations about Manston (eg. palleted instruments, a log fence, quite close to a massively wide runway) but it is reasonable.

I note the Met Office compare Brogdale with a wide area of stations but omit Manston, the only climatic station in the region. When I went down their list, oh dear, cherry picking poor sites. (might show some of the incidentals eventually)

As it happens I’ve spotted a new problem at Brogdale, perhaps Tim’s equivalent of the Anthony Watts “air conditioners are attracted to thermometers”, something else. You’ll have to wait.

Comments
  1. Lance Wallace says:

    Looking at the first few cases, it appears that Tmax and Tmin are provided to one decimal point only, and then Tavg is rounded up in all cases, leading to an upward bias. This is the same convention adopted by the US CRN. When I complained to them about this, they informed me that they are “working on” a different approach, which might bring them into line with the ordinary physics approach of rounding up or down depending on the next-to-last digit of the sum of Tmax and Tmin (e.g., up if odd, leave if even). Just a small error that would not affect the trend, but still seems sloppy. Who knows how long it might take to replace this convention.

  2. tchannon says:

    I’d not come across the formal specification for climat. Enough was available to figure it out, the most useful being a WMO presentation style brickbat aimed at authors of climat data, ie, indirect complaining many got it wrong.

    What some of the data actually means, pass, can only guess.

    I’ve now looked more carefully and found what seems to be the full document.

    Article is updated.

    I’m struggling with so many loose ends so it probably looks and is sloppy.

    Anyone adding commentary and insight, excellent.

    CLIMAT stations are all around the world but being able to get a rough look at the location is a whole different game since you will have to find the thing. Mileage will vary. For the US the surfacestations project might have all you need.

  3. […] recent post talks about 20 UK CLIMAT stations, which are used to report to GHCN. It might be interesting to see where those stations are located […]

  4. Trev says:

    FWIW, I live near Benson and the conditions in that area always seem to throw up colder temperatures.

  5. ray kalon says:

    Hi, regarding the Brogdale 2003 reading following is an email I sent to weatherquest.co.uk (Jim Bacon)

    “Hi can anyone clarify what the hottest officially recorded temperature in the UK
    actually was. My query follows a recent visit to Brogdale Faversham -which is
    shown on the Met office site as the record. I queried the validity of the
    weather station there with some of the locals (it does not seem to be well
    sited) and was told a very strange story! Apparantly, the area was developed
    into a farmer`s market/tourist attraction a few years before and wanted some
    free publicity. Pallets of block paving setts on the site were found to
    significantly heat up the area where they were stored so they were deliberately
    moved around the weather station to see what would happen.
    Consequently an abnormally high temperature was recorded which was not verified
    until almost a week later by which time the setts had conveniently disappeared.
    Were these locals spinning me a yarn or not? I notice some sites show Gravesend
    as the official figure @38.1 c with Faversham @38.5 as unofficial and not
    conforming to the immediate area. Any insights please?…..
    I live approx. 10 miles from this site and have been able to make further
    enquiries. The results of these tend to make me think a few local “rascals” had
    more to do with this “record” than the sun ever did. I was in Canterbury on the
    day of this “record” and I personally felt the Faversham figure was an unlikely
    almost 2 degrees higher than where I was.
    Has anybody any further insight into this please?”

    The reply was interesting from Dan Holley

    “Being a wee lad of just 12 years old I remember our family car thermometer
    reading 40C on the A21 south of Flimwell (East Sussex) as we stopped at the
    Little Chef there…. but I suspect although our car was an official reading, it
    was probably non-operational 😉

    Any ideas? I know Philip Eden was quite strongly against this reading, but
    presumably the Met Office hold this as the official figure for the UK?

    Dan”

    And then the following

    “Ray
    Just to add, I should have deleted the internal email section of my reply and
    that is not meant to be forwarded outside of this conversation.

    Many thanks and good luck with your query. There is always going to be dabate
    about these things i guess.

    Best wishes
    Jim

    Good morning Ray,

    Thank you for the interesting insight into the complexity of temperature
    readings from Brogdale.

    It sounds as though you know more than I do about the local details on the site.

    I can only say that the Met Office is still regarding it as a record and as such
    I have nothing to add which could change that.

    I guess the discussion is really with the Met Office.

    Sorry not to be able to add to the discussion.

    Best wishes
    Jim”

    So does everybody (aside from the Met Office) regard the reading as a joke?