This Saturday, 21st June, people across the UK sweltered in temperatures reaching up to 32°C, a level of heat that scientists say is now a hundred times more likely to occur due to global warming. Researchers at Imperial College London and the World Weather Attribution group have concluded that human activities, mainly the burning of fossil fuels, have not only increased the likelihood of such heatwaves but also intensified their severity. Without the impact of climate change, a 32°C (89.6°F) day at this time of year would have been expected only once in about 2,500 years. Now, early summer heatwaves in Britain are typically 2 to 4°C hotter than they were in the past.
What can you do to reduce emissions?
As a consumer, you have a range of options to lower your carbon footprint and reduce your emissions, which will help combat climate change. Here are five things to consider:
1. Rethink Your Travel – Walk, cycle, take the bus or train, car-share, or switch to an EV; cutting routine petrol- or diesel-car miles is one of the fastest ways to lower emissions.
2. Improve Home Efficiency – Draught-proof doors and floors, top up loft and cavity-wall insulation, and drop your thermostat just 1 °C (try lower if you can), every degree could save up to 10 % on heating energy.
3. Switch to Renewable Power – Move to a 100 % renewable electricity tariff and, if possible, install rooftop solar panels or a heat pump to displace gas or oil heating. Also, consider a wood-burning stove for secondary heating in your home.
4. Upgrade to Energy Efficient Appliances – Pick A-rated (or A +++) machines, run dishwashers and washers only when full at 30 °C, and switch to LED bulbs throughout your home.
5. Buy Less – Make It Last – Repair electronics, extend clothing life, and favour second-hand over new; keeping clothes in use one-third longer could save 10 million t CO₂ eq annually in the UK.
The Dangers of Heat
High temperatures like we have seen this weekend can be fatal, particularly for older adults and people with chronic illnesses. The UK Health Security Agency has reported that heatwaves during the summers between 2020 and 2024 led to more than 10,000 premature deaths. Despite this, some experts argue that the government still needs to do more to prepare the country for increasingly severe heatwaves.
Sustained periods of high heat pose a unique danger because they leave little time for the body to cool down overnight.
Dr Ben Clarke, who contributed to the research, emphasised the clear link between this heatwave and human-driven warming: “Without our greenhouse gas emissions, this wouldn’t even be considered a heatwave,” he said.
The Bigger Picture: Escalating Climate Crisis
Last year, the Earth’s global average temperature hit a new record high, driven by ever-increasing carbon emissions from coal, oil, and gas. Experts warn that if emissions don’t decline within the next few years, the world will almost certainly exceed the internationally agreed 1.5°C limit above pre-industrial levels, a threshold beyond which extreme weather is expected to intensify further.
“Every fraction of a degree hotter means more frequent and more severe heatwaves here in the UK,” Clarke said. “ This translates into higher mortality, increased strain on the NHS, transport delays, and more challenging working conditions. The clearest solution is to transition to clean, renewable energy sources.”
Dr Friederike Otto, another researcher at Imperial College London, stressed that the threat of heat remains underestimated in Britain. “People still do not grasp how deadly heat can be, and the UK is simply not prepared,” she said. In April, the government’s independent Climate Change Committee described the UK’s approach to adapting to climate impacts as “inadequate, piecemeal and disjointed.”
Silent but Lethal
Dr Otto pointed out that heat waves are often dubbed “the silent killer” because their toll is not immediately visible in the streets. In Europe’s scorching summer of 2022, more than 60,000 people died due to extreme heat.
Maja Vahlberg, of the Red Cross Red Crescent Climate Centre, noted that most heat-related deaths happen quietly indoors, often affecting elderly people living alone or those with underlying heart and lung conditions.
Professor Mike Tipton, a human physiology expert at the University of Portsmouth, warned: “The human body is not built to withstand prolonged, intense heat like this. Climate change is now directly claiming British lives. Politicians and commentators who dismiss climate action need to confront this reality, because until we cut greenhouse gas emissions, these deadly episodes will only get worse.”
How the Risk Was Calculated
The research team used detailed climate models, including data from a similar heatwave in 2022, to rapidly assess how much more likely this weekend’s temperatures are due to global heating compared to pre-industrial conditions. Their analysis confirmed that the risk has soared.
Older people are most vulnerable, but the heat can also pose serious risks to others, especially if medications interfere with how the body regulates temperature. The scientists stressed that staying hydrated and managing indoor temperatures are crucial. Keeping windows and curtains closed during the day and ventilating at night can help cool homes, a significant concern in the UK, where recent studies suggest four out of five homes overheat during summer.
Looking Ahead: Rising Temperatures and Wildfire Threats
Britain experienced its first-ever temperatures above 40°C in 2022. According to the Met Office, there is now a 50/50 chance that the UK will see 40°C again within the next twelve years if warming continues, and temperatures as high as 45°C cannot be ruled out.
Heat is now deadlier than floods, earthquakes, or hurricanes combined, according to a report by Swiss Re, a leading global reinsurer. Their analysis reveals that up to half a million people worldwide die each year due to extreme heat. “Extreme heat was once called the ‘invisible peril’ because its effects are less dramatic than other natural disasters,” said Jérôme Haegeli, Swiss Re’s chief economist. “But with longer, hotter heatwaves becoming the norm, we must acknowledge the enormous toll they take on human life, infrastructure, agriculture, and healthcare.”
The UK’s unusually dry spring and soaring temperatures have also heightened the risk of wildfires. “We’ve already recorded the highest burned area on record this year,” said Theodore Keeping at Imperial College London. He urged the public to take extra precautions with open flames, barbecues, and discarded cigarettes.
We’re used to helping people keep warm! But here are a few tips on keeping cool during the summer:
Cool Your Body
Wear loose, light-coloured clothing made of breathable fabrics like cotton or linen.
Use a damp cloth, sponge, or cool shower to lower your skin temperature.
Soak feet or hands in a bowl of cool (not icy) water.
Use handheld fans or battery-powered fans if you have them.
Keep Your House Cool
Close windows and curtains/blinds during the hottest part of the day (late morning to evening) to block out heat.
Open windows at night and early morning when it’s cooler to let fresh air circulate.
Use light-coloured curtains and reflective window coverings if possible.
Switch off lights and electrical appliances you don’t need, they generate extra heat.
Stay Hydrated
Drink plenty of water — aim for small sips often rather than waiting to feel thirsty.
Avoid excess alcohol, caffeine, and sugary drinks, they can dehydrate you.
Eat lighter meals, and include foods with high water content (fruits, salads, yoghurt).
Plan Activities
Stay indoors or in the shade during the hottest hours (usually 11am–3pm).
Avoid strenuous exercise or physical work if you can; reschedule for cooler times.
If you must go outside, wear a wide-brimmed hat and sunglasses, and apply high-SPF sunscreen.
Check on Others
Look after elderly neighbours, family, and friends, and anyone with health conditions — they are at greater risk.
Never leave children, pets, or vulnerable people in a parked car, even for a short time.
Prepare for Sleep
Use light cotton bedding.
Consider sleeping downstairs or in the coolest part of your home.
Keep a bottle of water by the bed to sip if you wake feeling too warm.
