The Met Office’s claim that July 1 was the hottest July day on record has fallen flat after climate bloggers discovered that the temperature peak may have been caused by a plane landing at Heathrow.
Early July saw Britain basking in a brief heatwave, with air temperatures across much of south and east England hitting the mid 30’s centigrade. On July 1, the Met Office announced that the UK had recorded the hottest July day on record, with temperatures hitting 36.7° centigrade at Heathrow airport.
The claim was widely repeated in the media – the BBC’s headline read “Hottest July day ever recorded in UK”, while The Guardian opted for a live blog under the headline “Heatwave live: Britain swelters on hottest July day on record”.
But eagle-eyed climate bloggers immediately spotted a problem with the so-called ‘record’: it was measured at Heathrow airport, where the hot tarmac and plane engines pumping out hot air can raise local temperatures by as much as two degrees.
Christopher Booker, blogging at the Telegraph pointed out: Even the Met Office’s own hourly record only showed its highest Heathrow reading on Wednesday as 35.9C, while four other sites nearby showed the day’s hottest recording at just 35C.
He also noted that: “Even if 36.7C was genuinely the hottest July reading since records were kept, this would still have been way short of the 38.5C recorded at Faversham on August 16 2003; or that famous day, August 3 1990, when Cheltenham registered 37.1C and local records were broken all over the country, which still stand.”
When asked for the readings to support the claim, the Met Office at first responded that it was happy to release them – for a fee of £75 + VAT. But such was the level of speculation that a few days later it capitulated, releasing the data on its blog where it insisted that: “Although Heathrow measured the highest temperature recorded by the Met Office observing network on a July day, record temperatures were reported across a wide stretch of the country, including from some of the Met Office’s very long running climate stations.”
It also asserted that “Temperatures exceeded 35 °C at a handful of locations in London and the south east, but also reached the low 30s across the Midlands, East Anglia and parts of north-west and north-east England. It is in these areas that July temperature records were broken.”
But Paul Homewood, who blogs at ‘Not A Lot of People Know That’, has highlighted a number of holes in the Met Office’s claims.
The data “totally fails to address the issue of how you can compare Heathrow with Wisley, where the previous July record was set,” he wrote. “The fact that Heathrow has “standard instruments” is neither here nor there.
“On the contrary, it highlights the concern that airport temperature stations were never set up to be used for climatological purposes.
“Put another way, would the Met Office like to estimate how much Heathrow’s temperatures are artificially inflated by the proximity of tarmac and jet engines?”
He concludes “The question of whether this spike at Heathrow was at least in part caused by a small windshift, bringing air from the runway, certainly does not go away.”
Homewood goes on to completely demolish the Met’s secondary claim that temperatures across the midlands and north broke July temperature records, pointing out that the Central England Temperature dataset, which records the average temperature across central England from 1659 to today, show that higher temperatures were reached in both July 1976 and August 1990.
Two years ago The Spectator published an article which highlighted a string of meteorological events in Britain that the Met Office had wrongly forecast, and accused the organisation of being “a propagandist for global warming alarmism” and “an accomplice to a climate change agenda.” It seems little has changed.