Giants Causeway DCNN 9146 – Hiding in the undergrowth.

55.234334 -6.512080 Met Office CIMO Assessed Class 4 Installed 10/5/2011.

The Giants Causeway weather station is located by one of the many car parks for the World Heritage site and about 500 metres from the coast. A footpath from the car park takes visitors close by the screen itself but most of those walkers will probably pass by the enclosure blissfully unaware of its existence. There are no online or street view images I could find which seems hardly surprising.

To avoid the risk of overly boring readers I could quote dozens of “official” Met office proclamations of how good they are and how carefully well sited and maintained their sites are -so here is just one.

https://weather.metoffice.gov.uk/learn-about/how-forecasts-are-made/observations/weather-stations

What is even more absurd is that with 87% of their sites failing to meet the acceptable quality standard for accurate climate data reporting of CIMO classes 1 or 2, the Met office then goes on to make excuses for why they claim they cannot meet reasonable standards. This is their explanation.

“The WMO Siting Classification for Surface Observing Stations on Land was formally introduced from 2014, enabling us to make broad comparisons of our weather and climate stations with those around the world. These WMO classifications focus on the exposure of an observed element at a site, with a Class 1 assessment being the highest standard and Class 5 the lowest. These classifications were added to the existing Met Office inspection process, complementing existing assessments around exposure, such as shading and heat sinks/sources, and are now routinely reviewed and updated as part of Met Office site inspection visits.

WMO Siting Classifications were designed with reference to a wide range of global environments and the higher classes can be difficult to achieve in the more-densely populated and higher latitude UK. For example, the criteria for a Class 1 rating for temperature suits wide open flat areas with little or no human influenced land use and high amounts of continuous sunshine reaching the screen all year around, however, these conditions are relatively rare in the UK. Mid and higher latitude sites will, additionally, receive more shading from low sun angles than some other stations globally, so shading will most commonly result in a higher CIMO classification – most Stevenson Screens in the UK are class 3 or 4 for temperature as a result but continue to produce valid high-quality data. WMO guidance does, in fact, not preclude use of Class 5 temperature sites – the WMO classification simply informs the data user of the geographical scale of a site’s representativity of the surrounding environment – the smaller the siting class, the higher the representativeness of the measurement for a wide area.  Indeed, it should be noted that WMO Class 5 is not the same as a Met Office ‘Unsatisfactory’ inspection assessment, which ultimately determines the ongoing use of a site. We use the Met Office grading system to determine record verification because; it has historical relevance, covering a wide range of long-standing criteria at UK observation sites, the equipment, and the exposure in a holistic manner and has clear meaning to what is acceptable or not. It tells us how much confidence we have in the data and permits comparisons.  “

The Met Office is clearly posting DISINFORMATION. It is not at all difficult to achieve Class 1 or 2 in the UK If there claim were genuinely true, how would it be possible for the likes of Harpenden just to the north of London or Thomastown in Northern Ireland to make a high standard. It is not a tenable argument to claim difficulty when simultaneously proclaiming national records from Class 5 Junk Cambridge University Botanic Gardens when barely a few miles away Class 1 Cambridge NIAB was not recording as high.

In the specific case of Giants Causeway it is quite obvious that no attempt whatsoever was made in trying to establish a good quality site – by the Met office’s own unique assessment system this site should be classified as “Unsatisfactory” in being completely surround by walls of high vegetation.This image dates to just 6 months after original installation in 2011.

The screen has, weirdly typically, been situated in the extreme corner of the enclosure (similar to Kewand dozens of others) and directly alongside the cut out walls of gorse. That gorse grows to a mature height of up to 2.4 metres/8 feet and even from natural sowing can reach 2 metres /6 feet in between 8 to 10 years. This is how ChatGPT offered an enhanced image from the above Google Earth Pro 2D image to sharpen focus.

The obvious question is what on earth was the Met Office employee who chose this point and whoever installed it actually thinking of? This site was never going to be representative of anywhere other than the few square metres of the enclosure. The surrounding gorse was only ever going to grow taller and thicker with the likelihood of anyone actually reducing that growth close to zero.

One thing that is certain is that with the absence of any wind penetrating down to the 1.2 metre base height of the screen most of the time, that this site will often be artificially much warmer than the surrounding open countryside overnight and likely to overheat in strong sunshine during the day. Both resultant effects will elevate temperature data input for that area. Furthermore, the wider angle view demonstrates just how untypical the chosen location actually is – it would be very hard to actually find a worse location than was chosen with open expanses of green fields everywhere around.

For scale here is the view of the start of the footpath from the car park up to the enclosure and onto the cove. Consider the height of the cars and the bench seat to gauge how tall the gorse surrounding the screen is likely to be.

How data from this site is likely to be used adds to the truly weird nature of the site and perhaps explains the reasoning behind its siting.

The nearest quoted “Climate Station is Portrush which was 6 miles east along the coast. It closed in 2003 and it seems likely the Giants Causeway site was selected as its replacement for that “Gridded Cell” area. The problem was that Portrush was not really producing the “desired” results.

Compare the 1991 to 2020 minimums above to the 1961 to 2020 below

Portrush was only showing a 0.55°C increment in minimumm readings averaged over the 60 year period. Now compare that to suitably relocated and modified next nearest climate station of Ballypatrick Forest.

!991 to 2020 above, 1961 to 1990 below

Now that is much more like it! A 1.15°C increment in minimums (over double that at Portrush) is what is required. It was probably too embarrassing to admit that such a huge discrepancy is almost entirely due to poor original siting, inadequate site maintenance, relocation, instrument and reading protocol changes and nothing to do with CO2 molecules or “existential crises”.

Any Portrush replacement had to produce the “right” results so put it in a compromised site that is bound to increase overnight minimum recordings – where else! That may sound a cynical assessment of the motivations but what other justification can there be for what appears to be deliberately poor station siting which, I repeat, can only be regarded as “Unsatisfactory” by the Met Office’s own unique assessment system.

The Met Office itself is operating in an unsatisfactory manner.

Source: https://tallbloke.wordpress.com/2026/06/22/giants-causeway-dcnn-9146-hiding-in-the-undergrowth/