We shall continue to have abnormally hot summers from time to time, just as we did in 1976 and 1846, way back before global warming was invented.
There is at least one thing about this summer of 2018 on which we can all agree: the past months have unquestionably been swelteringly, abnormally hot.
And not just here in Britain, but in many other countries right across the northern hemisphere.
In the UK, our own heatwave began in May and has continued relentlessly ever since. In Japan, where one city claimed the highest temperature ever recorded in that country, topping 106 degrees Fahrenheit (41 degrees Centigrade), the heatwave has been declared ‘a natural disaster’.
Meanwhile, wildfires in Greece have killed at least 80 people, leading to claims that this has been the worst disaster of its kind seen in Europe since World War II.
There have been numerous other claims of temperature records being broken, all the way from California to Armenia and Azerbaijan (although here in Britain we have not so far seen anything to equal the 101.3f — 38.5c — that was recorded near Faversham, Kent, on August 10, 2003).
But more sober experts have raised question marks over the reliability of these temperature measurements, because of the siting of the thermometers which recorded them.
In every case, it turned out, they broke the golden rule that such thermometers must not be placed near heat-retaining structures or surfaces, such as in the centre of large cities, near airport runways or on Tarmac car parks.
This is because their readings are then distorted by the so-called ‘urban heat island effect’, which can exaggerate temperatures by up to 2 degrees Celsius or more.
One comical example of this was on June 28, when the UK Met Office rushed to announce that the 91.7f (33.2c) reached at Motherwell made it the hottest temperature recorded in Scotland.
Only when it was pointed out that its thermometer was in the middle of a Tarmac car park did the Met Office hastily withdraw its claim, with the rather sad explanation that the reading had been distorted by a ‘car left nearby with its engine running’.
But all these excitable little mishaps notwithstanding, it has certainly been abnormally hot. Above all, this raises the question: how unprecedented has this summer’s heat really been? And, secondly, how long was it going to be before certain climate scientists came round to telling us that this was unquestionably proof the world is in the grip of man-made global warming?
At last this week they have come in on cue, with Peter Stott, head of climate change predictions at the Met Office, and Rowan Sutton, head of atmospheric science at Reading University, both making that point loud and clear.
As Professor Sutton told us on yesterday’s BBC Radio 4 Today programme, thanks to climate change we can expect summers like this one to become more frequent. And even if we curb our carbon dioxide emissions in accord with the famous Paris climate agreement of 2015, this will continue for decades to come.
Perhaps it is time, therefore, to start looking at some proper historical evidence in order to gain a more balanced perspective on what is really going on.
For a start, here in the UK we have the longest-running set of temperature data in the world, the Central England Temperature Record (CET), which goes back to 1659. And this shows that June of this year was only the 18th warmest June in more than 350 years — the hottest being as long ago as 1846.
So this kind of summer heat is far from unprecedented. In fact, as people have begun to observe, the nearest parallel to what has been happening this year was the celebrated ‘drought summer’ of 1976.
That was the year when, as older folk vividly recall, the heatwave lasted virtually unbroken for three months, until rain finally came at the end of August. And, according to the CET, those daily temperatures 42 years ago frequently beat this summer’s figures hands down,
But there is another striking parallel between this year and 1976 — as there also is with that other heatwave summer of 2003 when the highest single temperature ever recorded in Britain was set.
In each case the cause of the prolonged heat has been a large area of high pressure that has sucked in hot air from the Sahara (when my next-door neighbour returned to Heathrow this week, she found her car covered in this desert sand).
This in turn has been caused and prolonged by a movement of the jet stream (which dictates much of the northern hemisphere’s weather conditions) because of cooler ocean temperatures in the Atlantic. This movement has kept lower-pressure weather formations containing moister and cooler air parked further out in the Atlantic to the north-west of Britain and Europe.
Although the causes of this cooler Atlantic are an entirely natural cyclical shift, the global warming-obsessed Met Office became so excited by that heatwave in 2003 that the following year it produced a report based on computer models, called Uncertainty, Risk And Climate Change.
This predicted that baking summers would soon be so frequent that by 2040 more than half of Europe’s summers would be hotter than 2003.
But the same 2004 report predicted that by 2014, global temperatures would have risen by 0.3c. In fact, during those ten years, temperatures recorded by weather satellites did not rise at all. Neither, until the past few weeks, have we seen a single summer to compete with the sweltering 2003.
We need to recall such facts, if only to remind ourselves that there are those so convinced of their particular theory of how climate works that they will leap on any evidence which seems to confirm that they and their computer models are correct.