Middle Wallop WMO 03749 – The focal point of car (and other) exhausts.

51.14986 -1.56999 Met Office CIMO Assessed Class 4 Installed 1/1/1959 Temperature data archived from 1/3/1984

I consider Middle Wallop to be a classic example of the Met Office creative tape measuring system. Rather than following the guiding principle of the CIMO classification system, i.e. to provide a standardised representation of the natural environment to provide international data comparison, they have followed the letter of the law not the “spirit”

To go through the technicalities of the exact dimensions the screen has to be from “extraneous” heat sources, the 10 metre circled area just manages not to include any car exhausts and not too much of all the surrounding hard standing. A tiny, fenced-in grass island within a sea of concrete, tarmac, buildings, cars, conventional aircraft and helicopters would not be most people’s chosen location for accurate temperature readings.

I am sure it is stating the obvious that those determining such distance regulations did not expect such rather silly locations as above to be used. It would almost certainly have been their intention to ensure no heated draughts would be able to influence readings. Such a heated draught problem is NOT just those car exhausts, the circled areas just north of the screen are helicopter landing pads as seen in use below. If the car exhausts do not effect the readings from the south,then the helicopters do from the north.

Have Met Office staff never been in the vicinity of a helicopter take off or landing? Somewhat unlikely as so many train at Navy, Army Air Corps or Air Force establishments.

I find it quite appalling that such a compromised location should be used at all to contribute readings to the historic temperature record. Worse still is that the Met Office should effectively bend the spirit of the regulations so wantonly. If this site has to be classified, then it is unquestionably Class 5 (not class 4) and inaccurate by up to an additional 5°C.

Or is there an alternative motive? As noted in a Met Office observers guest post

“For example a site on an airport may present no problems for a MiG; the quicker response of the Pt may catch a quick burst of an aeroplane’s exhaust as it passes en route for take-off or landing.   This will result in a higher Maximum Temperature recorded for that day.“

As noted in the review of Wiggonholt, the “crossing of thresholds” seems to be equally important to promote as “evidence” as potentially inflated average temperatures from poorly sited weather stations do. For example, in this BBC article its Lead Weather Presenter (and RAF Officer) Simon King proclaimed –

Most would accept that Army Air Corps Middle Wallop (being inland from the coast in warm Hampshire) is very much more likely to record 30°C or higher when temperatures are read by highly responsive and modern electronic instrumentation having track-side heated air blown at it from car exhausts and helicopter rotors. Are these higher temperatures really a “result of climate change” as an RAF Officer instructs us to believe rather than selected location of readings? Not a lot of those conditions around in the early 20th century….and meteorologists were much more careful in their choice of location for weather stations back then.