Merryfield DCNN 8672 – Ultra Modern Standards but where? Met Office withholding information.

50.96104 -2.93348 Met Office assessed CIMO Class 4 installed 10/5/2021

There is a weather station in the above image that is less than 4 years old……but where on earth is it? It took me several hours to track it down as the Met Office supplied co-ordinates somewhat improbably located it in the trees to the south of the airfield. This seemed strange as this site only dates from May 2021 and should be an example of meeting modern standards. There certainly was no shortage of space to fit it in.

So where actually is it? To help with locating from the headline image, a general close up indicates the red kite is 100 metres from the runway and 45 metres from the taxiway.

Further close up, with 10 metre circle marking, reveals the screen is within the Control Tower compound next to the transmitter tower, close to the large scale security fencing and in the low sun shade of a building to the north east with its walls just 5 metres away.

So, yet again, what does the Met Office say about this sort of siting?

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

“For example, official weather stations are often located at airports as they have plenty of open space making them a good place for observations to take place.” – Seriously? There is lots of open space at Merryfield so why locate the screen in the most compromised and tiny spot of the entire site?

And then. ” However, the observation equipment is set an internationally-agreed distance from the runway to ensure no external factors can influence readings in any way.” My first point to make on this is that presumably the Met Office prefers their “external factors” (security fencing, transmitter masts, building walls and shade) to be much, much closer as at Merryfield.

The second point though is, that when I reviewed St Athan on the 1st October I also asked the Met office to clarify both exactly what this “internationally-agreed distance” was and what was defined as a runway as opposed to a taxiway. In the two months since they have declined to directly answer such elementary questions and only referred me to non specific documentation not supporting their case. I have now had to resort to the following Freedom Of Information request:

“Date and time Notification record created: 29/11/2024 21:35:41 GMT

Contact details: ray.m.sanders1956@gmail.com

Short Description: Freedom of information request

Description: This email was received from an external source. Always check sender details, links & attachments.

I made the following request of your enquiries desk but as usual they
completely evaded answering. So I ask the question under FOI.
Your website
https://www.metoffice.gov.uk/weather/learn-about/how-forecasts-are-made/observations/weather-stations
is very specific in stating the following.

“For example, official weather stations are often located at airports as
they have plenty of open space making them a good place for observations to
take place. However, the observation equipment is set an
internationally-agreed distance from the runway to ensure no external
factors can influence readings in any way.”

Please could you advise me what exactly this “internationally
-agreed” distance is and where it is specified. Could you also define what
is meant by “runway” as opposed to, for example, “taxiway”

I trust you will understand my need for clarity given these examples and
many others.

https://www.google.co.uk/maps/place/57%C2%B012’18.2%22N+2%C2%B012’19.2%22W/@57.2050627,-2.2078999,589m/data=!3m2!1e3!4b1!4m4!3m3!8m2!3d57.2050598!4d-2.205325?entry=ttu&g_ep=EgoyMDI0MTExMy4xIKXMDSoASAFQAw%3D%3D

https://www.google.co.uk/maps/place/51%C2%B024’19.6%22N+3%C2%B026’26.7%22W/@51.4054418,-3.443318,678m/data=!3m2!1e3!4b1!4m4!3m3!8m2!3d51.4054385!4d-3.4407431?entry=ttu&g_ep=EgoyMDI0MTExMy4xIKXMDSoASAFQAw%3D%3

Regards
Ray Sanders”

The date by which they have to answer such an innocuous question is 31st December, so hopefully in the New Year, I should be able to offer some enlightenment into this issue. The fact that this has to be taken to FOI is, however, frankly absurd – what is there to be hidden? Could it be that either very few of their aviation sites actually meet these claimed standards or, equally possibly as I suspect, no such standard exists.

Coming back to Merryfield, this is a very new site well after the 2014 establishment of ISO/WMO guidelines. Simply classing the site as very low standard with inaccuracy by siting of 2°C makes a complete mockery of the Met Office claims their instrumentation is accurate to the 5th decimal point of a single degree.