South Farnborough Sites – Analysis of changes over time. Location really does matter.

South Farnborough No 2 51.28439 -0.77839 Met Office CIMO Assessed Class 2 Installed 17/12/2021

The history of sites in and around Farnborough Airport dates back to the earliest days of aviation when the first UK heavier than air powered flight took place there in 1908. There have been 4 different identified sites over the intervening years. The meteorological variations between them, the way much of the information has been concealed and the potential manipulation of site choices are the main topics of this review.

Firstly the above site known as South Farnborough no 2 is Met Office assessed as meeting Class 2. The above image indicates the 30 metre radius circled area which should be free from extraneous heat sources and meet ALL the following regulations.

At first glance from the headline image this site may well meet those standards, however, closer examination reveals significant problems – I assess this site as Class 4 at best. Checking out the Ordnance Survey sheet for the area relief (normally unnecessary for an airfield site as they are generally very flat by their nature) indicates some nearby “hache marks” indicative of steep gradient.

A closer look from the current Google Street view image confirmed artificial earth works almost certainly from the early 21st century modifications to the road network in that area, rerouting water courses and sound screening from the airport activities.

The surrounding tree lines alone are likely to compromise the site with both sun shading and wind sheltering. The roadways around are very extensive and (from personal experience) frequently very busy indeed. The wind issue will be further exacerbated by the extensive wire fencing enclosing the area. The earthworks are clearly of significant height – I estimate approximately 4 metres high with an online measuring tool suggesting the gradient starts at 16 metres from the screen. I find it implausible that Met Office assessors can be using the same interpretations of CIMO regulations that make so many rural sites (for example Ipstones Edge) marked down as Class 4 whilst these seriously compromised UHI/Airfield perimeter sites as Class 2.

The obvious question though is, does this really matter? Well, as the Met Office’s own data demonstrates it most certainly makes a very significant difference when put into context of former sites and the immediate average temperature uplift that can be achieved by a relocation. The site history becomes crucial to explain and the comparative data indicates remarkable differences.

In 2012 Tim Channon briefly reviewed NOT this site but the previous South Farnborough site. Tim did not have then benefit of the Met Office assessement back then but certainly knew his stuff and when viewed in hindsight called almost every single one exactly as the Met office went on to in 2014. Here is his opinion on the previous site.

Whatever anyone’s views of aviation sites may be, this South Farnborough location definitely met Class 1 beyond any doubt. This location is listed as running from 1/1/1914 (when the original Airship Balloon site acquired its first “runway”) up to 12/7/2022. {N.B. as will be analysed further in this review this created a readings overlap period of seven months with the No 2 site having opened on 17/12/2021}

However, this Class 1 site was not the original location. All the digitalised archive data (only covering from 1921) shown as “South Farnborough” give the coordinates of the above site. Despite previous sites being known, it is common practise for the Met Office to not openly archive this data as I have frequently noted in these reviews typically as at Marham. Deep in the archive notes is the comment.

The remains of this site can be seen on Google Earth Pro historic images as below from 1995.

This previous location clearly was a very poor one for climate reporting purposes but it seems it was only relocated due to further development around it. Going even further back in time the period prior to digital archives from 1914 to 1921 was yet another different location again a substantial distance away though I am not able to pinpoint exactly from the relatively imprecise coordinates given.

Summarising all this site history and marking the known sites with distances on a map.

1. Site one from 1914 to 1921 exact location not known.
2. Site two from 1921 to 1994 potentially low grade site.
3. Site three from 1994 to 2022 Class 1
4. Renamed site from 2021 claimed Class 2 more reasonably Class 4

Importantly archived digital data does not openly indicate any moves and suggests a continuous record from one location. Whether the above points are relevant or not depends on how the data is presented. Below is the Location Specific Long Term climate averages for South Farnborough giving 30 year rolling averages from 1961 through to 2020.

This presentation does not indicate any moves and incorrectly implies a continuous single record. Adding more context, in reviewing Braemar no 2 , I demonstrated how the Met office had also seamlessly bonded data from two climatologically different sites into one “Historic Record” named from the newer (and warmer recording) “No 2” site. So does this have any relevance to the new South Farnborough No 2 only recently instlalled? Remember that overlap period for 7 months when both the old and new sites were simultaneously recording – how did the readings compare?

I set about finding out – just the first pass of the earliest 14 days overlap period from 18/12/2021 revealed some alarming discrepancies. Both sites record twice daily at 09:00 and 21:00 for both maxima and minima so 28 readings for each for the period.

In terms of minima, of these 28 options , the new SF2 site recorded warmer than its older neighbour on 16 occasions, with 12 being the same and NONE recording colder. Ignoring the reification of averages, the hard number differences ranged as follows. 6 @ +0.1°C, 2 @ +0.3, 1 @ +0.4, 1 @ +0.5, 2 @ +0.6, 1 @ +0.9, 1 @ +1.1, 1 @ 1.2 and astonishingly 1 @ 1.7.

In terms of maxima of the 28 options, SF2 recorded colder by just 0.2°C on 3 occasions, the same reading on 6 occasions and again warmer on the majority at 19 times. The warmer maxima were much less ranging between 0.1 to 0.3°C. Notably, on every single day the average temperature was warmer at the new South Farnborough No 2 over the older (Class 1) South Farnborough site 630 metres away. This warranted a much longer period investigation (particularly of that major night time discrepancy) I set about doing this manually, gave up and contacted an expert – Dave Woolcock.

“Hi Ray

see attached – your suspicions appear to be pretty well founded.

tMax is very slightly down BUT with some wacky outliers

tMin is WAY increased

seal wadding indeed.”

Dave examined every individual reading for the overlap period and then compiled a histogram showing the range of differences spread over a total of 4.3 °C. Are there any meteorologists who seriously believe the weather could consistently be so different , over such a short distance and at the same elevation for wholly natural reasons?

The screen capture extract below demonstrates Dave’s diligence in examining every single entry – no fudges, estimates nor adjustments required – just hard numbers.

A close up of the graph demonstrates the consistency of the difference. This reminded me of Dr Eric Huxter’s wry comment in his guest post on PRTs regarding the readings from Heathrow

“It is interesting that one of the CIMO 3 stations is Heathrow, whose 1.48°C/hour change would place it as an extreme CIMO 5 station. Who knew?”

The data evidenced from comparing South Farnborough No 2 with its Class 1 near neighbour and predecessor of a 4.3°C range indicates this new site is more likely ” 2.6 Class 5 (additional estimated uncertainty added by siting up to 5 °C) Site not meeting the requirements of class 4.” Furthermore the marked major uplift in minima supports the issue recently highlighted by Anthony Watts

https://climaterealism.com/2025/06/warmer-summers-not-so-fast-axios-nighttime-lows-drive-the-heat-not-daytime-highs/

To greater clarity to Dave’s graphics:

In 5 years time the Met Office will publish their 30 year rolling climate averages for the period 2000 to 2030 – the first full climate averaging period of the 21st century – and will no doubt by then have updated their list of “Historic Stations”. In exactly the same way as they did not openly disclose the 1994 site relocation, and in the same way that Braemar No 2 (and others) “absorbed” data from an earlier different site, I anticipate the new station’s warmer data will bond onto the older ones. The rolling period will have almost 9 full years of warmer readings feeding through to “prove” the required agenda which will continue to worsen as the older stations cooler readings progressively “dilute” 2. If that may seem a cynical view, at least it is one that is now on record for future reference. Anthropogenic warming but nothing concerned with Carbon Dioxide.

Source: https://tallbloke.wordpress.com/2025/06/06/south-farnborough-sites-analysis-of-changes-over-time-location-really-does-matter/