Extreme Heat: Preparedness

Extreme heat is also an occupational health risk. Employers will increasingly need practical measures such as water, shade, ventilation, rest breaks and adjusted working patterns. Stronger workplace protections would safeguard both workers’ health and productivity. The private Member’s Bill in the name of my hon. Friend the Member for Gorton and Denton (Hannah Spencer) recognises that existing protections have not kept pace with our changing climate, and that employers need to be supported to ensure that people are working in safe and healthy conditions.

Britain’s buildings were designed for a cooler climate. During heatwaves, schools, hospitals, libraries, prisons and care homes can become dangerously hot, placing public services under additional pressure just as demand is rising.

This year’s record-breaking spring heat provided a warning, with high demand and low storage levels leaving thousands of households in south-east England without water. Building resilience means expanding reservoir capacity, modernising ageing infrastructure, reducing leakage, improving water efficiency and restoring natural catchments. Water security is no longer simply an environmental issue. It is fundamental to public health, food production, economic resilience and national security.

Extreme heat is becoming one of the greatest threats facing farmers and our food system. Predictable seasons, reliable rainfall and healthy soils are at extreme risk from climate breakdown. The National Farmers’ Union describes climate change as

“one of the biggest threats to UK food security”,

while 80% of farmers say that increasingly frequent extreme weather is threatening their livelihoods and reducing productivity. Heat stress is also threatening animal welfare. During the 2022 heatwave, when UK temperatures exceeded 40° for the first time, around 18,500 chickens died from heat in transit. Government figures indicate that more poultry died during the heatwaves we have experienced this summer.

Higher temperatures dry soils, increase irrigation demand and reduce crop yields. This year’s dry spring brought harvests forward into late June in some areas, with lower spring yields expected as a result. Many farmers can now harvest only in the mornings and evenings because grain becomes too dry during the hottest parts of the day, which increases storage fire risks and, in some cases, necessitates costly cooling before processing. The Climate Change Committee estimates that heat stress already costs agriculture around £205 million a year. Last year’s spring, the hottest and driest on record, contributed to one of the poorest harvests in recent decades, costing arable farmers at least £800 million in lost revenue.

The consequences extend far beyond the farm gate. The UK food security digest concludes that climate-related disruption is already pushing up food prices, while the Energy and Climate Intelligence Unit estimates that extreme weather added around £361 to the average household food bill during 2022 and 2023. As Britain becomes more reliant on imported food, we are increasingly exposed to climate shocks overseas, with disruption to just five staple foods estimated to have driven 30% to 40% of food price inflation over the past two years. Climate change is no longer just affecting where food is grown; it is affecting what families can afford. Supporting farmers through resilient farming systems, better water management, healthier soils, stronger animal welfare and continued innovation is essential to protecting affordable food, rural livelihoods and the resilience of Britain’s food supply. Food security is national security.

Wildfires are becoming a growing challenge for farmers and fire and rescue services. They are occurring earlier, lasting longer and increasingly threatening homes, businesses, infrastructure and rural communities. Hotter, drier summers dry vegetation and soils, allowing fires to spread rapidly and causing devastating damage to crops, wildlife and property. As the climate warms, fire and rescue services will need greater capability, stronger land management and better public awareness. Wildfire resilience must become a central part of Britain’s climate adaptation strategy.

Britain’s wildlife is experiencing the consequences of hotter, drier summers as well. Rivers and lakes warm rapidly during prolonged heat, reducing oxygen levels and contributing to fish deaths and declines in freshwater biodiversity. Wetlands dry out, placing pressures on amphibians, insects and water birds, while prolonged heat and drought weaken woodlands and leave ecosystems more vulnerable to pests, disease and wildfire.

Those impacts come on top of decades of habitat loss and ecological decline. The Wildlife Trust warns that climate change is amplifying the nature crisis, while the Royal Society for the Protection of Birds has highlighted that important habitats, including peatlands, salt marshes, heathlands and wetlands, are becoming increasingly vulnerable to prolonged heat and drought. The problem we have is a lack of real-time data on ecological impacts.

All of that matters, because healthy ecosystems are part of our national resilience. The Climate Change Committee increasingly describes healthy ecosystems not simply as environmental assets, but as part of the nation’s resilience infrastructure. Healthy ecosystems store water, cool communities, reduce flood risk and support biodiversity. Peatlands store carbon and retain water during periods of drought. Wetlands help to regulate river flows, reduce flood risk and provide cooler refuges during heatwaves. Trees and woodlands lower surrounding temperatures, helping to cool both urban and rural environments while supporting biodiversity.

If we continue to lose the natural environments that regulate water, cool our towns and cities, retain fresh water and sustain biodiversity, we will become progressively less resilient to the impacts of climate change. Protecting and restoring nature is therefore not simply an environmental ambition; it is an essential part of preparing Britain for a hotter future.

In conclusion, the costs of extreme heat are already being paid. Dame Emma Howard Boyd, chair of the National Heat Risk Commission, has described extreme heat as a “force multiplier”, because it increases healthcare costs, disrupts transport and energy systems, damages crops, raises food prices and places growing pressure on water supplies and wildfire risk.

The June 2026 heatwave alone is estimated to have reduced UK productivity by at least £2.36 billion and, as that figure reflects only productivity losses, the true economic impact is almost certainly higher. If current trends continue, annual productivity losses could reach £25 billion by 2030. The Climate Change Committee estimates that around £11 billion a year is needed to strengthen the UK’s climate resilience, with around a third of that invested in protection from extreme heat. Adaptation is an investment in resilience, and prevention will always be cheaper than recovery.

What is lacking is not evidence, but co-ordinated delivery. Britain needs a heat resilience strategy that is led from the Cabinet Office, with clear ministerial accountability, ensuring that decisions on housing, infrastructure, health, energy and land use are all designed for the climates that we now face. Heat health warnings, public information and targeted support for vulnerable people should become routine before heatwaves strike. Green infrastructure is among the most effective adaptation measures available, but adaptation alone cannot protect us from unchecked warming, and mitigation cannot protect us from the warming already locked in. We need both.

A world that warms by 4° would bring dire consequences beyond the limits of adaptation, making climate resilience and decarbonisation inseparable. The challenge before Parliament is therefore not whether to act, but whether we act quickly enough and with enough ambition to prepare Britain for the climate in which we must now live.