51.70292 -5.15201 Met Office CIMO Assessed Class 4S Archived temperature readings from 1/1/1959
Dale Peninsula protrudes from the south west of Wales in the old ceremonial county of Pembrokshire. The Fort was built in the mid 19th century as a coastal artillery defense that has since been adopted by the Field Studies Council as an educational facility. Unfortunately over recent years the husbandry of the weather station has fallen to the FSC and therein lies a major problem.
The CEDA archives have only digitally transcribed readings from 1959, this is odd in that records are readily available from 1950 onwards. It is worth noting that the transcribers of the 1959 to 1961 readings operated to the Met Office “rounding up” process making 31°F equate to – 0.6°C with 33°F becoming + 0.6°C unlike Faskally where rounding down was operated generating different conversions with a 0.2°C discrepancy.
Reading frequency up to the early 2000s was highly commendable as it should be for every manual climate reporting station. However, as is so typical of almost every FSC run site, the readings became erratic to the point of rarely being taken. As the Met Office enquiries desk offered to Dave Woolcock who was searching for data from Mickleham .
“Looking at Mickleham it is a Field Studies Council site.
This means that it has a high turnover of staff usually with a new observer each year. They tend to need to have one committed member of staff to keep engagement going, even if they are the supervisor not necessarily taking the readings. When they move on engagement drops off sharply. I would guess that is what happened at this site.
Over the last 10 years or so, there has been a general drop off in observations from all of our FSC sites. We get peaks when a new person starts and is enthused, then it drops off again as they get busy with other duties.”
Given that the sole purpose of any weather station is to supply instrumental readings, there really is little point if no readings are taken. A typical recent example year (not the worst) was 2016 when only 138 readings (38% of the year) were actually taken. It is not only the infrequency that is of concern though, actually reading LIGTs is a trained skill in order to avoid parallax reading errors. This site was fitted with a digital PRT in 2017 but that only records maxima in manual stations with LIGT still employed for minima. If observers are not adequately trained or committed to the task, errors are inevitable. A point that always confuses me is the recent nature of this observing infrequency generally. As I noted in reviewing the premier quality Lake Vynwy, in the latter 20th century readings were meticulously taken however adverse the conditions, this diligence seems to have been lost at far too many sites and not just FSC run sites.
So what of the site characteristics – well they really are far from ideal. The weather station will not have been established for the purposes of creating a long term climate record rather for very localised military purposes. As the Met Office itself used to openly admit many years ago
“The location of the site should be selected in such a way that the observations are representative on a scale required from the station; a station in the synoptic network should make observations to meet synoptic scale requirements, a rainfall station should measure the impact of local orography on the rainfall amount, while an aviation station should observe the local conditions at the aerodrome.“
A weather station at a coastal artillery defense base does not report conditions with the inland area in mind so will never be representative of anywhere else. Again this adoption of inappropriate weather stations for general climate use was similarly acknowledged after having detailed the site requirements they state.
“It is unavoidable that some sites do not meet all these requirements, particularly where a station set up for one purpose gradually takes on a different role, for example an airport site originally established for aviation observing may become a key synoptic or climate station while suffering the effects of urbanisation. A few sites are in city centres and may be unsuitably located close to large obstacles or even on the roof of a building.”
Dale Fort weather station sits in a semicircular concrete emplacement surrounded by a wide range of huge stone and concrete structures and is astonishingly unnatural. The FSC produced a drone flyover film for publicity on Youtube that gives a very good insight to the overall unsuitable nature of the site for climate reporting. The weather station is clearly visible at around 1 minute in and is by the wind mast mid right of centre in the still below.
The Met Office assesses the site as Class 4S with the addition of the “S” intended to indicate severe shading effects to be taken into “consideration”. Presumably the walling around the site and the few shrubs and trees are the cause of this problem, in which case I fail to see why the site is simply not considered Class 5. It really is a poor site for climate reporting which now has a very poor reporting record – put together, no use at all despite a long term record.
To add typically perverse logic to Met Office data presentation we move onto their inevitable 60 year rolling climate averaging. With a continuous observations record from 1950, Dale Fort, in theory, would be a suitable candidate for their location specific long term climate averages reports…….or maybe not if they do not recall having a climate station there. “Sorry we don’t have any climate stations at or nearby that location” Really?
So putting in the FSC postcode SA62 3RD we are invited to examine comparative data from 4 miles away at Brawdy.
Brawdy (better known originally as RAF Brawdy) is, of course, one of those sites that are totally inappropriate – “for example an airport site originally established for aviation observing may become a key synoptic or climate station” To add further perversity Brawdy was opened in 1955 (subsequent to Dale Fort) and closed 33 years ago in 1992. The Met Office prefers to portray its “data” for climate averages purposes from fabricated numbers for non existent sites in lieu of real numbers from existing ones…… And then they refuse to divulge which site’s data were used in this fabrication. If Dale Fort and RAF Brawdy are only 4 miles apart why not simply use the real site’s data for the entire period of 1961 to 2020 rather than computer generated numbers from a largely “imaginary” site?
The Met Office cannot be allowed to continue in a manner that accepts multiple “slap dash” readings from a multitude of wholly inappropriate sites in order to computer fabricate unaudited alarmist figures from their pet Zombie sites which are kept a “state secret”.
via Tallbloke’s Talkshop
July 8, 2025 at 03:22AM
Iowa Climate Science Education 