{"id":71412,"date":"2024-06-01T05:00:00","date_gmt":"2024-06-01T04:00:00","guid":{"rendered":"https:\/\/www.lse.ac.uk\/granthaminstitute\/?post_type=news&p=71412"},"modified":"2024-09-18T15:32:27","modified_gmt":"2024-09-18T14:32:27","slug":"combining-early-warning-systems-and-long-term-preparedness-for-heat-in-the-uk-this-summer-and-for-the-long-haul","status":"publish","type":"news","link":"https:\/\/www.lse.ac.uk\/granthaminstitute\/news\/combining-early-warning-systems-and-long-term-preparedness-for-heat-in-the-uk-this-summer-and-for-the-long-haul\/","title":{"rendered":"Combining early warning systems and long-term preparedness for heat in the UK \u2013 this summer and for the long haul"},"content":{"rendered":"\n

As the UK enters its period of summer heat health alerts, Candice Howarth and Anna Beswick explain the role of this important early warning system in the context of insufficient preparedness for extreme heat.<\/p>\n\n\n\n

The Heat Health Alert (HHA) system<\/path><\/svg><\/a> is an early warning system that issues alerts from yellow through to orange or red when high temperatures are likely to have an impact on people’s health and wellbeing. It is operated by the UK Health Security Agency (UKHSA) and the Met Office, who work together to monitor weather forecasts and assess the level of risk. Between 1 June and 30 September, individuals and organisations can receive heat health alerts if they register their details<\/path><\/svg><\/a> and heat–health planners are provided with regular weather–health horizon-scanning twice a week to support emergency planning.<\/p>\n\n\n\n

The Met Office’s three-month outlook<\/path><\/svg><\/a> for June to August suggests the chance of a hot summer is “slightly higher than normal”, which “brings an increased likelihood of heatwaves and heat-related impacts”. If a heatwave or high temperatures that take us above certain temperature thresholds occur, then we could see an alert issued. The red alert<\/a>, indicating the greatest risk, has so far been issued only once, on 19 July 2022, when the UK experienced temperatures over 40°C. Close to 3,000 heat-related deaths occurred that summer.<\/p>\n\n\n\n

Our own research<\/a> analysing England’s responses to the 2022 heatwaves concluded that the UK is not prepared for extreme heat. With projections indicating we are likely to see more heatwave events in future, early warning systems such as the HHA have an important role to play but there is also far more to be done.<\/p>\n\n\n\n

Is heat risk increasing?<\/h2>\n\n\n\n

Due to climate change, heatwaves are increasing in severity and intensity across the world<\/path><\/svg><\/a>, impacting the built and natural environment, people and wildlife, and posing ever greater risks to health, wellbeing and productivity. Extreme heat events are here to stay, both in Britain and globally.<\/p>\n\n\n\n

The UK’s average summer is expected<\/path><\/svg><\/a> to be around 1.5°C warmer by the 2050s compared with the 1981–2000 average and 10% drier. By 2100, temperatures exceeding 40°C could occur every 3.5 years<\/path><\/svg><\/a> under a high-emissions scenario.<\/p>\n\n\n\n

But temperatures do not need to exceed 40°C or even 30°C before the impacts of heat are felt. Once the mercury registers 25°C, the number of heat-related deaths can increase by around 30% in England and 60% in Wales<\/path><\/svg><\/a>. And we know that the majority of heat-related deaths and health impacts are preventable using simple measures<\/path><\/svg><\/a>.<\/p>\n\n\n\n

The UK experienced five heatwave periods over the summer of 2022, with a wide range of impacts including more excess heat-related deaths than in previous years and especially severe health impacts for at-risk groups such as the elderly and young children. On the day of the red alert, 19 July, a series of wildfires occurred, and the London Fire Brigade called it their busiest day since World War II<\/path><\/svg><\/a>.<\/p>\n\n\n\n

How does heat affect us and why does this matter?<\/h2>\n\n\n\n

Heat risk is often referred to as a silent killer. It does not affect everyone equally<\/path><\/svg><\/a> and is compounded by and exacerbates health, social and economic inequalities. Over the past few months we have been hearing from people across London who are affected by extreme heat in their communities through a project in collaboration with Shade the UK<\/path><\/svg><\/a>, findings of which will be published later this summer. Informed by these local experiences and other research, we know that the impacts of heat risk are far-reaching:<\/p>\n\n\n\n