56.02824 -4.98503 Met Office Assessed CIMO Class 4 Installed 11/1/1949
Benmore is the fourth of a highly questionable quartet all under the auspices of the Royal Botanic Gardens Edinburgh with other sites in the capital, Logan and Dawyck. All of this quartet are CIMO Class 4 and NONE of their readings should be included in the national historic temperature record.
At the risk of repeating myself, it should be obvious that walled gardens are deliberately intended to NOT reflect the natural environment. It is the walls and surrounding windbreak trees function to modify the immediate locality and create an artificial micro-climate that is significantly warmer than otherwise would be. The Royal Botanic gardens own websites regularly proclaim the range of plants and trees that grow there from all manner of exotic places that would never normally survive there. Whilst recording the weather conditions will be vital for the local horticulturalists the readings are completely meaningless for the purposes of recording the natural climate. That this obvious point seems lost on the “climate scientists” at the Met Office is beyond reason.
This is a very attractive site that I personally would like to visit but it really is not a good place to compare the temperature readings of 75 years ago with those of today.
Perhaps just as importantly though is the question whether this is actually a good place to be forecasting weather from. The Surface Stations Project aim is to evaluate all UK weather stations and their suitability for data inclusion in the historic temperature record. The RBG Edinburgh group sites are not suitable for that purpose. Other functions of weather stations such as forecasting are generally outside the project scope. However, a number of comments posted have raised the issue of poor accuracy of forecasts in Scotland generally. On inspection it is easy to see that the nature of many Scottish weather stations makes them unrepresentative not only for historic temperature recording but also forecasting.
A disproportionate number (almost half) of Scottish sites are manually reporting and only supplying data up to 24 hours in arrears rather than instantly available automatic sites. Comparatively less than a third of English stations report manually. There are a surprising number of sites similar to this RBG group which are located in walled gardens – indeed walled gardens are very much a Scottish feature due to the generally more severe climate inhibiting natural growth. A scan through the list of Climate and Synoptic stations reveals a large number of “Castle” and “Gardens” sites. I have reviewed many so far notably the briefly proclaimed Scottish record holder at Floors Castle.
This map of only automatic reporting sites from Weatherobs (screen captured at 10:00 am 12/1/2025) shows a large proportion of island sites. Whilst these will help indicate weather front movements they also demonstrate huge temperature differentials from +9°C to -8 °C over geographically relatively short distances. As I demonstrated with the comparison between Stowe and Oxford, site selection can create very different averages. The potential variation that can be derived by site selection in Scotland is potentially massive. The broadcast of weather forecasts must need to be very tightly area specific to have any real meaning.
Another oddity is the number of coastal aviation sites mostly to the east. The distorting effect of huge areas of black tarmac causes rapid daily overheating but can also have a reverse nighttime effect. The close up of the infamous Dyce (literally a short walk from the Met Office’s Scottish HQ) and more representative Craibstone shows a naturally improbable real time variation of 4°C over a distance of just 2.7 miles.
When the unique area stations such as Cairngorm Chairlift and Aviemore are taken out of the numbers there are actually very few locations representing the bulk of the Scottish mainland. This suggests not only is the historic temperature record heavily compromised by unrepresentative sites but also that immediate weather forecasting is probably not being best served as so many have noted in comments.
And then of course there is Pollok Country Park weather station! Need I say more?
via Tallbloke’s Talkshop
January 12, 2025 at 05:26AM
