David Craig, on July 26th, 2019(Friday blog)
Here’s a line from a Times article today bleating about supposed Global Warming (or Climate Change or Human Extinction or whatever it’s called this week): “Measured in Cambridge at 3.37pm, it beat the previous record for July of 36.7C, which was set at Heathrow in 2015. It was only 0.4C shy of the hottest temperature on record — 38.5C in Faversham, Kent, in 2003”.
Let’s take a few moments to analyse this latest scaremongering eco-posturing
Cambridge – more people, more offices, more cars, more air-conditioning
What do we know about Cambridge? Well, it’s got a jolly good university. And there’s a river full of punts. It’s also one of the fastest-growing cities in Britain:
(Sorry that the graph is difficult to read. I’m not sure why there’s a drop at the end in 2017. I think this is because 2017 is an estimate)
The city continues to grow as ever more hi-tech and medical companies set up operations in the city to take advantage of the large number of highly-educated, highly-skilled people living there.
The population density for Cambridge is now over 3,000 people per km2. So, this once pleasant, largely-academic, semi-rural country town now has similar population density to places like Wolverhampton, Coventry and Derby. More people and more modern air-conditioned offices mean more heat. So, as Cambridge grows and grows, there will be an ever greater ‘heat island’ effect.
An ‘urban heat island’ is an urban area or metropolitan area that is significantly warmer than its surrounding rural areas due to human activities. The temperature difference usually is larger at night than during the day, and is most apparent when winds are weak.
Even if there wasn’t any Global Warming, we would expect the hottest temperatures in fast-growing, heat-island Cambridge to increase.
Why is Heathrow hot?
Then there are temperatures at Heathrow Airport – another place the BBC and mainstream media love to quote when trying to scare us with the threat of catastrophic Global Warming. What do we know about Heathrow? Well there are lots of lovely heat-reflecting tarmac, lots of heat-emitting planes and lovely large heat-emitting passenger terminals.
There has been relentless growth in Heathrow passenger numbers:
Moreover, there has also been massive growth in the population of Southeast England resulting in the M25 (which passes through Heathrow Airport) being log-jammed with heat-belching lorries and cars for much of the day. If ever there was a place in Britain with a major ‘heat island’ effect, it would be Heathrow Airport.
What about Paris?
There also loads of news reports about how Paris is also apparently “sweltering under record temperatures”. Here’s a graph of the French capital’s population growth:
More people = more cars, more buildings, more heat.
Of course, it has been hot in Paris. But when claiming heat records have been broken, the climate change doom-mongers never mention how rapidly-increasing populations can increase the ‘heat island’ effect.
Car parks can get hot
Here’s nice photo of a weather station measuring temperatures:
What do you notice? Yup, it’s in the middle of a car park and near some heat-emitting air-conditioned buildings. And this is apparently a problem with many hundreds of weather stations. They used to be located in the countryside. But as towns and cities have expanded, many weather stations that used to be in the middle of nice, cool, heat-absorbing fields are now in heat-reflecting car parks and beside heat-producing buildings. So, these weather stations would probably record hotter temperatures whether the climate was warming or not.
The situation is so bad that in 2018, the Met Office actually rejected a claim that Scotland had experienced its hottest day:
And the reason the Met Office rejected this ‘hottest day’ claim? Yup, you guessed it – the temperature measurement was taken in the middle of a car park. And what do you have in a car park? Yup, heat-belching cars.
Caveat emptor
I am not denying that the climate is changing. The climate is always changing. And I do not deny that the climate may be warming as we move from the Little Ice Age into the Modern Warm Period:
I’m only suggesting that we exercise a little caution when being bombarded with the mainstream media’s ever more hyperventilating claims of “hottest day ever” and “temperature records broken” and “we’re all going to die”.
Category: 
No wonder we are obsessed with the temperatures when the human race has become so stupid that we have to be told in newspapers and on TV about how to keep cool. So what do people do, they go to one of the hottest places, the beach, and sit in the sun getting cancer. I was looking forward to Portillo’s series last night about the Tories only to find that I had recorded a load of rubbish about the heat wave.
You are correct about temperature measurements but overall the number of measurement points has reduced over the years with a trend away from country sites and towards cities. This will be countered by a claim that we have more accurate satellite measurements. I haven’t managed to discover what is being measured. The system uses radiation from oxygen but it seems to be an average over a depth of the atmosphere. These temperatures will never be used in the way that actual surface measurements are being used because they will be lower.
The biggest issue is that the earth can only be warming if it is receiving more heat from somewhere and the atmosphere cannot generate heat. The earth’s internal heat and the heat we produce are ignored. The only heat source is the sun and it is said that there is no change in the output. Obviously not since we have no control over it. What we have seen recently is not temperatures resulting from an increase in the energy of the heat source, this is just heat flow higher temperature regions to Europe. It is not usual, but it happens. At a basic level, thermodynamics is easy. There is a heat source and then energy flow through the system. Just like home heating – the energy source is the flame in the boiler and the heat flows through the radiators into the room and out through the wall and the temperature decreases as the heat flows through the system. Another key issue is that as heat flows, one part cools when another part warms, so what is the average?. The radiators have to cool as the rooms warm. The heat we have received results in somewhere else cooling. The earth warms, the earth cools.
Whilst money is being poured into meaningless research on CO2 and means to reduce it nothing is being done to understand the actual causes of climate change. The need for air conditioning is now being talked about. Where is the energy going to come from if fossil fuels are banned. The climate policies are damaging our economy but China ignores then. It is easy to see what changes the near future will bring.
Northolt is another place in London that often sets records. Which coincidentally also has an airport and no guesses where the victorian measuring box is located.
Thank you David for another dose of cool common sense to moderate yesterday’s media-generated hysteria. Car parks, airports, many urban developments, particularly high-rise and those bereft of all green stuff, are vile places – stiflingly hot in summer, windswept and arctic in winter. I suppose almost all today’s reporters are too young to have experienced or remember the summers of 1975 and 1976, when we enjoyed – yes, we did enjoy – two or three months of glorious weather. Day-long sunshine, baking temperatures. And know what? We carried on as normal. We studied, we worked, we got to our jobs in schools, offices, hospitals. We got our kids to school and we collected them at the end of the day, fed them and got them to bed. We slept with our windows open, under just a sheet. Hose-pipe bans were universal and those of us with gardens tipped our washing up and laundry water into buckets and watered our plants. (Many of us didn’t then have dishwashers or washing machines.) I have no evidence to prove it of course, but subjectively I consider that at least where I live yesterday was slightly less hot than many of those July and August days more than 40 years ago. What’s the saying? Lies, damned lies and statistics. Statistics can certainly lie if not acquired with utter impartiality and probity.
Stillreading: In 1975-6 the concept of global warming was not on anybody’s mind. They might have been talking about the next ice age. The highest temperature in 1976 was 35.9 on 3 July but I only checked one reference. Meanwhile on the Tour de France the stage today was cancelled because of snow on the road and landslides. Of course one day of high temperature has no relevance. It is the annual earth’s average temperature that matters according to the experts but there’s nothing like talking up the crisis.