Britain’s weather is uniquely suited to making polite conversation: it’s both highly changeable and, in general, less of a threat to life and property than the extremes of other countries. We have heatwaves in February and chilly days in summer, giving us cause for wonder and complaint. We have rain and storms, but don’t experience monsoons or hurricanes.
That’s changing. On the morning of 19 July last year, the temperature hit 40.3C at Coningsby in Lincolnshire. By the end of the day, 46 weather stations across the country had exceeded the previous high of 38.7C.
What was notable was that the record was broken not by fractions but by more than a degree. That, and that it was broken in so many places, from Kent to Yorkshire.
And yet we aren’t really used to seeing this as a problem. A few weeks after the new record was set, the Met Office weather presenter Aidan McGivern appeared on GB News and faced an interrogation about why he wasn’t talking about the heat as a good news story. Instead of presenting an upbeat view, forecasters were ordered to deliver warnings, the presenter suggested. “You’re told to say things like: ‘Don’t have a barbecue in case you burn the local park down’. People aren’t stupid are they, Aidan?”
The weather has always made the news, though. And weather forecasting has always been about weighing risk as well as reporting the state of the atmosphere. The BBC began daily radio broadcasts in November 1922. The first programme was a news bulletin, and the second was a weather forecast, prepared by the Met Office. Few records have been kept of early broadcasts, but one of the news headlines was about fog causing disruption in London.
By March 1923, weather forecasts were broadcast daily. In January 1954, the meteorologist George Cowling became the first weather presenter to appear on screen, telling viewers that high winds would make the following day a good one to hang out the laundry.
A few years later, in March 1958, the scientist Dave Keeling began recording the atmospheric concentration of carbon dioxide on the north slope of the Mauna Loa volcano on Hawaii’s Big Island. The first reading was 313 parts per million (ppm), a little above the 280 ppm mark, where data from ice cores tells us it stood for 6,000 years of human history, aside from ice ages when it fell lower.
In 2021, that figure for the concentration of CO2 in the atmosphere went over 420ppm, the highest since measurement began and indeed the highest for millions of years – since an era when the poles were 5-10C hotter than they are today and the sea level was 35 metres higher. The Keeling curve zigzags a little with seasonal variation as plants grow and absorb carbon dioxide in spring and summer, but overall it has swept relentlessly upwards since that first reading.
Technological improvement means forecasts are now more accurate than they were decades ago. Despite this, forecasters emphasise probability and uncertainty more than in the past because the technique now is to run multiple computer models rather than just one, tweaking the starting conditions slightly each time and taking a sample across the range of outcomes – a method known as ensemble forecasting. If there’s a narrower range of outcomes from the modelling, this allows forecasters to speak with higher certainty.
The Met Office was founded in 1854 by Robert FitzRoy, a vice-admiral in the Royal Navy and the commander of HMS Beagle on Charles Darwin’s voyage around the world. It occupies an elegant glass and steel building on Fitzroy Road, on the outskirts of Exeter. There’s a supercomputer housed in rows of grey boxes in the basement, and upper floors where forecasters sit at banks of screens showing weather systems sweeping in from the North Atlantic. On a damp January day, McGivern, one of its senior presenters, reflects on last summer’s extraordinary heat.
Fifteen days before that heatwave, a single ensemble forecasting run generated a prediction of 40C temperatures. McGivern says: “It was one out of 50 so you would say that’s very unlikely at that point. That was your first ‘sit up and take notice’ moment. That was the first time we’d seen 40 degrees appear on a computer model.”
As the day approached, more and more of the computer modelling runs were producing a 40C scenario, and some went higher – an even higher temperature would have been possible that day if winds had been lighter, or blown from a different direction.
His initial reaction to the models was disbelief. A few years ago, McGivern made a “future weather forecast” using computer modelling that takes into account the concentration of carbon dioxide in the atmosphere by the middle of this century. It begins like this:
“Hello, it’s Friday the 22nd of July 2050 and it’s been another extremely hot day across the UK. However, there is a glimmer of hope for some cooler conditions towards the middle of next week.”
In the future forecast, which is meant to help businesses anticipate hotter conditions, McGivern spoke of highs of 40C-plus. “What I never thought would happen was that we would see it as early as 2022,” he says. “It’s fascinating from a meteorological point of view to see any kind of extreme weather unfold and at the same time it’s scary.”
Polling shows that climate scepticism is a minority view, and most people in Britain believe climate change is at least partly responsible for heatwaves. Extreme heat also drives concern about climate change in the UK. That tallies with research across Europe which shows that climate shocks can increase public support for climate action, though this only applies when economic conditions are favourable.
Still, while a majority in Britain accept that heatwaves can be a risk to others, research conducted for the Red Cross found that most people do not believe we are at risk ourselves – even those in vulnerable sections of the population like those aged 75 and over. A heatwave isn’t as dramatic as a hurricane toppling trees or snowdrifts closing motorways and airports, though it can be more deadly.
Our understanding of the risk is beginning to change. Construction companies shut sites last summer, while pubs and restaurants closed as it was too hot for staff to work safely in kitchens. Cities across the world, from Greece to Sierra Leone, have now appointed chief heat officers to make their citizens’ lives bearable in temperatures that will be higher for longer. But the fact that we’re still waking up to the risk, and are so accustomed to seeing the heat as a blessing, means forecasters have to work hard to communicate the danger.
Context is important when choosing what language to use, McGivern suggests. If it’s the first warm spell after a wet spring, the tone is upbeat. “If it’s a 40-degree heatwave, it’s unprecedented and it’s the kind of heat we know causes health impacts, we’ll be much more serious with our messaging,” he says.
There’s less use these days of the kind of filler phrases forecasters often used in the past – “a lovely day to go to the park” – in favour of distilling information into broadcast bulletins that are often briefer than they used to be, while social media and continuous channels offer an opportunity for greater volume and depth. As well as Twitter and TikTok, the Met Office is experimenting with 20-minute forecasts on YouTube.
The history of forecasting in the UK is entwined with the imperative to save lives. After the “Royal Charter gale” of 1859 – a storm in the Irish Sea that claimed 800 lives – Met Office founder Vice-Admiral FitzRoy proposed a national storm warning system based on the weather observations his office was gathering.
The first storm warning was issued in 1861, using a system of drums and cones hoisted on flagpoles on the coast to warn ships of an approaching gale. (The warning was ignored on the Tyne, the Met Office notes, and many lives were lost).
Following the Great Storm of 1987, the Met Office set up the National Severe Weather Warning Service, to alert the government and public to the impact of potentially disruptive weather.
The weather now, and the environment as a whole, bears the imprint of humanity’s activity. Fittingly, perhaps, thinking of the weather as a person can help us understand the risk. “When we name a storm then, almost always, it starts trending on social media,” McGivern says. “It’s much easier to communicate impacts from a named storm, because you’ve got something to reference. When Storm Eunice happened in February 2022, surveys showed 99 per cent of people in the red warning area were aware of it, and 90 per cent took action.”
With “Zoe” last summer, the city of Seville became the first place in the world to start naming heatwaves. The Met Office, which names storms in conjunction with its Irish and Dutch counterparts, is discussing the idea of naming heatwaves with European partner agencies. The complicating factor is that heatwaves cover a large area, requiring consensus among a number of countries, and can stay in place much longer than a storm.
Forecasters say climate change looms increasingly large in their work, and they grapple with the balance between their day-to-day work, helping people plan their lives around the weather, and the need to explain the broader narrative of an altering world. There’s a loud minority who are resistant to hearing it. The BBC’s forecasters received hundreds of abusive messages, via Twitter and email, questioning their reports on the extreme heat last summer.
Downstairs from the room where robotic cameras film forecasters at the BBC’s new Broadcasting House, BBC forecaster Matt Taylor recalls the wave of hostility his work provoked. “Most weather forecasters were just bombarded. I wasn’t alone. For me it was the first time I’d seen it on that scale.”
Some of the criticism was flavoured with hazy childhood memories, including recollections of the unusually hot summer of 1976. Yet the UK’s ten warmest years on record have all been in the last two decades.
Taylor says: “There are some who won’t listen and are not willing to engage in anything other than denial. There is another section of the audience… I think if you present facts in a rational way rather than doing it in too emotional a way… if I show you average temperatures now compared with decades ago, you can see there is a trend.”
He is conscious of the risk of being a fire alarm that’s going off continuously. “If you over-warn, it’s human nature to switch off. You save certain words, you save extreme words for when you know there is going to be a high impact.”
Alongside the criticism, the BBC’s audience research teams found a demand for information during the heatwave, though. As well as searching for the forecast, people were also looking for practical information on staying cool. Forecasters tapped into this, weaving in advice on mitigating the effects of heat.
“The public has a greater thirst for knowledge,” Taylor says. “When there is some flooding or a spell of heat on the way, quite often the public will say, is this climate change?”
It isn’t always. Attribution science determines whether climate change made an extreme weather event more severe or more likely. The European summer heatwave of 2003, blamed for more than 20,000 deaths, was the subject of the first attribution study. That research found that human influence had doubled the likelihood of a heatwave of this severity.
The cool and wet weather that we often complain about in Britain also allows us to be outdoors in most seasons. The shift to hotter, dryer summers and to warmer and wetter weather in winter is one that will change our lives.
We’ll need to get used to extremes and accept the impact of a changing climate throughout our society, from the challenges of maintaining essential infrastructure such as power cables to commuting to city centre offices to enjoying outdoor sports and festivals.
Forecasting the weather will become more critical than ever before. And the task of communicating our anticipated pleasure and likely risk in the weather will be more delicate than ever.
Jeevan Vasagar is climate editor at Tortoise.
This piece was first published in the latest edition of Tortoise Quarterly, our short book of long stories. Pick up a physical copy in our shop at a special member price.
Photographs Getty Images