The year 1659 appears with remarkable frequency in the media in
connection with the English climate, often in the form “since records
began in 1659”. It is a statement rarely if every questioned by
anyone with access to the mainstream media.
Just pause and think about that claim. Does it seem probable that
official weather records have been meticulously kept for three and a
half centuries, kept before the scientific and industrial revolutions,
kept before the English or British state became a bureaucratic monster?
The answer of course is that it is extremely improbable and did not
happen. What did happen in the third quarter of the last century is that
a British meteorologist by the name of Gordon Manley attempted to
produce an historical series for temperature in England which he
eventually extended to 1659. His work over a quarter of a century is
summarised in two papers published by the Royal Meteorological Society:
The mean temperature of central England 1698-1952 (1953) and Central
England temperatures – monthly means 1959-1973 (1974) The two papers
can be found at http://www.rmets.org/publication/classics/cp1.php Other
academics have built on his work since.
Manley, like a good academic, was scrupulous in admitting the
difficulties in constructing such an historical series: “Methods of
approximation must be resorted to [when constructing any historical
series], most notably in England where, despite our very long
scientific tradition, almost all observation before 1841 was dependant
on amateur effort so that widely scattered records of diverse length and
accuracy provide endless problems… The English records offer a
formidable problem”. The opening paragraph of his 1953 paper.
“Formidable problem” is understating matters. Even readings of
temperature today using highly sophisticated equipment cause
considerable dispute because where the measurement is taken is all
important, for example, readings taken in or close to urban areas will
produce a higher temperature than ones taken in areas with little or no
human habitation. Trying to get a consistent environment to take
temperature over a long period of time is obviously difficult and
comparisons with the past questionable because we can never know what
the conditions were exactly at any point in the past. Hence, even with
the advent of official records early in Victoria’s reign it is not
simply a question of comparing data from one time with another. For
example, has can temperatures in London today be meaningfully compared
with those of 150 years ago when there were no motorised vehicles and
coal was the main energy source?
Once Manley enters the period before the official records (pre 1841) his
caveats become ever more severe, whether it be the paucity of the data,
breaks in the data, the widely different means used to collect data, the
absence of any information about how data was collected and even the
switch between the Julian to the Gregorian calendar in 1752 which means
every record prior to the change has to be recalibrated to the
Manley’s research and analysis was honest but the most rational thing
to conclude from it is that it proved no meaningful historical
temperature series for England could be constructed over the period.
Yet his research is trotted out as having the status of certain fact by
the mainstream media, politicians and, to their shame, often by
scientists when they enter the realm of public debate.