Mickleham DCNN 5255 – Intermittent Average Negligence.

51.26095 -0.32048 Met Office assessed CIMO Class 5 & UNSATISFACTORY Installed 1/1/1899

The Met Office itself rates this station in the lowest possible category of Class 5 with an error margin of up to 5°C. It has also rated it by its own standards as “UNSATISFACTORY” (Met Office capitalisation not mine) but still continues to use the readings……on the rare occasions when the readings are actually taken. Mickleham has the distinction over recent years of the fewest readings actually taken of any Met Office weather station in England.

This manual station dates back 125 years and lies just north of Dorking in Surrey. It is certainly not a remote nor difficult location to access. It seems remarkably disappointing that the site has been so neglected. A relatively small amount of attention to the overgrown shrubs and trees would surely raise this otherwise open countryside site to a good standard. A waste of an otherwise useful asset.

Taking the daily readings is the responsibility of the staff of the Field Studies Council centre. As was shown by the case of Nettlecombe these staff are not always the most diligent observers.

Under Freedom of Information Act the Met Office supplied annual temperature averages for all stations in England which also indicated the annual number of observations made. Ideally these readings should be 365 (or 366) annually but inevitably there will be some occasions where some days are missed – usually only a few.

However, in the case of Mickleham in 2021 just 19 days readings were taken.

In 2022 an “improvement” to 75 days.

However, in 2023 recidivism took over and readings dropped to just 43.

It is wholly unacceptable for the Met Office to allow such negligence to continue.

I shall leave it to others to comment on the standards of stewardship of its assets the Met Office employs, however, the way the Met Office has used the limited data from Mickleham is even worse. Despite very limited numbers of observations ranging from barely 20% to just 5% of annual readings they have still derived an annual mean daily temperature. Who knew that Surrey was so much colder than Cumbria (Maulds Meaburn) or Derbyshire (Middleton, Hillside) as shown above? Or that Mickleham was, on average, 4 degrees colder than Charlwood just a few miles away?

It seems that the function of achieving an annual average daily temperature for each and every site is much more important than the actual derived figure having any real meaning. This quite arithmetically meaningless way the Met Office employs in “averaging” is “UNSATISFACTORY” in more ways than one.

Source: https://tallbloke.wordpress.com/2024/10/07/mickleham-dcnn-5255-intermittent-average-negligence/