Camden Square DCNN5038 – Unveiling the mystery and analysing UHI.

51.54407 -0.13418 Pre CIMO Assessments but unquestionably Class 5 installed 1858 closed 1957.

51.54452 -0.13246 Pre Cimo Assessments again unquestionably Class 5 Installed 1957 closed 1969.

Following some recent comments made on “X” (formerly twitter) I feel it is necessary to clear up some issues regarding the Talkshop’s Surface Stations Project and UHI.

Firstly the purpose is purely one of research with most certainly no predetermined outcome. Each and every current weather station plus important historic sites are being assessed against CIMO siting standards taking into account initial installation, any relocations and/or site location changes and any other alterations of any form over time. The data accuracy, observational frequency and any adjustments made to data are investigated. The “presentation” of data is of significance in reference to whether the same sites or datasets are being used over time. In the process of investigations numerous other issues have been uncovered including over/under representation of geographic areas, nature of sites (aviation, walled garden etc) choice of modern site installation, instrumentation changes and several other issues.

Urban Heat Island effect is one issue I only raise where it is of specific relation to a site – typical examples being St James’s Park London and Sheffield. Probably the ultimate example of long term UHI is a site that has enjoyed almost “cult status” from its ability of holding onto long term high temperature records which, in reality, were only achieved by its archetypical UHI affected readings – Camden Square. …..This makes it a vital reference point. Three of the 12 monthly high temperature records (25%!) are still (some jointly) held by Camden . The list in full:

So what is the history of this Camden Square site? A review by Philip Eden former Vice President of the Royal Meteorological Society.

“Camden Square was established by G.J.Symons around 1860. He lived and worked there (the weather station was in a moderately large walled garden) and he produced the monthly issues of Symons’s Meteorological Magazine and the annual volumes of British Rainfall. Symons died in 1900 and his work was continued briefly by H.Sowerby Wallis and then by Hugh Robert Mill. Mill retired in about 1920 and the British Rainfall Organisation was subsumed into the Meteorological Office, and the two publications were subsequently published by the Met Office — until 1968 in the case of British Rainfall (although it is interesting to note that the terms under which the Met Office took over the BRO required them to continue publication “in perpetuity”), and until about 1993 in the case of the Meteorological Magazine. The property at Camden Square was acquired by the Royal Meteorological Society in 1922, and the observations were continued by housekeepers until 1957. The station was then moved a short distance to the gardens in Camden Square where it continued until 1969.
Camden Square was the only long-standing inner-London climatological station which was in a thoroughly urban environment — the others, such as Regent’s Park, St James’s Park, Kensington Gardens, were in parks, or in the case of the Air Ministry (subsequently London Weather Centre) on a rooftop. It is therefore a very rare commodity in that it provides us with an idea of the inner-city climate. That’s why it was so warm.

Philip Eden
11th July 2003″

I am certainly not about to query the opinion of such an internationally esteemed meteorologist who coincidentally so distrusted elements of the modern day Met Office “Climate Scientists” that he established his own version of the Central England Temperature Record in “competition” with the Met Office version.

{For a period early in the 21st century there were two versions of the series: the “official” version maintained by the Hadley Centre in Exeter, and a version that was maintained by the late Philip Eden which he argued was more consistent with the series as originally compiled by Manley.}

Obviously Camden Square was subject to UHI that has not materially changed for a very long time and even despite the advent of motorised transport is even today probably no better, nor worse, than 167 years ago when originally established. This image from 1945.

It is safe to say that in 1945 this site was as compromised by urban activities then as it is now – a very important point to note. To re-quote Philip Eden “That’s why it was so warm.” The advantage is that it establishes a benchmark of UHI from which to operate future comparisons which, try as the Met Office might, have not been broken. Comparing the “like for like” of UHI distorted readings versus UHI distorted readings effectively shows no change in the top extreme. Multiple, and additional , London UHI affected sites have not broken the top end BUT observations demonstrate that temperature minima have been affected by the incremental number of sites recording UHI elevated night time readings and thus artificially elevating the crude “meteorological mean“

How does the Met Office present Camden Square’s data? It would appear they would prefer it did not exist and it would not surprise me that they may soon try to expunge its readings from the records entirely – they do not produce much of them now anyway.

The Historic Stations data webpage includes sites such as Dunstaffnage and Yeovilton (both yet to be reviewed) dating from 1971 and 1964 respectively but no mention of Camden Square with records from over a century before. Whilst this exclusion might be considered due to its closure, the same web site unashamedly includes Southampton:Mayflower Park that closed in 2001 and coincidentally shares that June 1976 record figure but with Camden Square achieving it in 1957 instead. Even that home of the undead Zombie stations – the Location Specific Long Term climate averages – chooses not to recognise it but perversely quotes 3 long dead sites at Hampstead, Greenwich and Northwood.

Perhaps the ultimate admission that the Met Office really does not like Camden Square weather station comes from its not even bothering to pass most of its readings into the CEDA digital archive archives. They only show temperature data for the 10 years from 1959 to 1969 from the latter relocated site and no readings at all from the original one despite its regular record setting achievements.

I find this remarkably strange given that all the readings are available in copied images such as this year below.

In summary (and to repeat) the Surface Stations Project is to objectively and scientifically review weather stations with no predetermined outcome. The Issue of UHI is not a dominant issue except where applicable. Camden Square not only demonstrates UHI better than probably most other sites but also acts as a level playing field benchmark for other equally UHI affected stations. That its records still stand indicates that UHI is not the all important factor, indeed indicates no historical change between typically intense UHI affected sites over time. It is the encroachments of urbanisation onto previously rural sites that is the crucial factor (i.e. site changes over time) and it is this aspect of UHI that warrants further investigation. So the front door of the site the Met Office really does not want you to know anything about.

Number 62 Camden Square London

Source: https://tallbloke.wordpress.com/2025/06/24/camden-square-dcnn5038-unveiling-the-mystery-and-analysing-uhi/