For those who can remember it, the summer of 1976 stands as a benchmark for extreme heat in the British Isles. That year brought severe drought, national water rationing, five days above 35°C in England and a scorching 35.9°C in Cheltenham – at the time, the second hottest day on record. It felt unprecedented.

Yet, a look at the latest Met Office figures, with records stretching back to 1884, reveals a clear and concerning trend. Four of the five highest UK temperatures have occurred since 2019. Topping the list is a staggering 40.3°C recorded in Lincolnshire in July 2022, with Cambridge hitting 38.7°C in 2019. The 1976 record now sits at a distant 13th place.

But these are just single days; to look at whole summers, meteorologists take the average temperature over June, July and August. While 1976 still ranks as the fifth hottest summer overall, the four warmest British summers on record were 2003, 2006, 2018 and 2022. And the Met Office data for 2025 already places this summer in the top 5%.

Typically, UK heatwaves happen when hot air moves north from Africa or Spain. However, this year is different. The Met Office has reported significantly warmer-than-average sea temperatures around the UK, with a marine heatwave impacting the waters off southern England, South Wales and the Irish Sea.

A high-pressure system has trapped warm, humid air masses from the Atlantic over the UK. This has allowed temperatures to climb daily under intense sunshine. The humidity also contributed to unusually high overnight temperatures.

This summer almost every country in Europe has experienced a heatwave, from Iceland to Turkey. But the warming isn’t confined to summer. When considering whole years, the past three years – 2022, 2023 and 2024 – are ranked by the Met Office as among the UK’s five warmest on record.

This isn’t a local anomaly. Globally, the picture is even clearer. The World Meteorological Organization has confirmed 2024 as the Earth’s warmest year on record, with 2023 as the second warmest. The last ten years (2015-2024) are now the ten warmest on record globally.

However you slice the data, our climate is unequivocally getting hotter, driven primarily by CO2 pollution from burning fossil fuels. The rate of warming is accelerating as the Earth’s natural carbon and heat absorption capacities (sinks) have become saturated. Recent decades show a significantly faster increase both in surface temperatures and ocean heat content than previous ones.

The Met Office warns that recent temperatures have far exceeded any in at least 300 years. Even more alarming is the projection that today’s high temperatures could be considered average by 2050 and even cool by 2070 – well within the lifetimes of today’s younger adults.

To secure a safer future for them, surely we can all find the collective will to accelerate our transition to electric vehicles, heat pumps, electric hobs and renewable energy sources like solar and wind power, and build the necessary energy infrastructure. The evidence is overwhelming; the time for decisive action is now.