Catherine Conlon: We need a Heat Plan for Cork as planet warms up

As a heat dome hovered over Europe last month, it reportedly caused dozens of deaths, disruption of power supplies and public transport, closure of schools and cultural landmarks, and threatened harvests. City living became close to unbearable.

In fact, the death toll is likely to be hugely underestimated as heat may worsen existing illness rather than appear as the sole cause of death. A research paper in Nature in 2025 estimated almost 63,000 heat-related deaths in Europe in 2024 while the Lancet Countdown report 2025 reported hundreds of thousands of people now die globally each year from heat.

Although Ireland sat on the edge of the heat dome, it is clear that Irish cities are no longer immune from hazardous temperatures in the summer. In response to repeated extreme heatwaves, London has developed its first ever heat plan to protect it citizens as temperatures soar. It provides a template for other European cities, including Irish ones to do the same.

Experts say the early season heatwave was part of a broader warming trend. Europe is the world’s fastest-warming continent, with temperatures rising about 0.56C per decade since the mid-1990s, more than double the global average. Climate change is making heatwaves more frequent and intense, and likely to occur earlier and later in the year.

Europe is particularly vulnerable – much of its housing and infrastructure was not built for prolonged extreme heat, and only about 20% of its homes have air conditioning. Structurally and culturally, much of Europe was not made for the heat.

Many European cities are broiling with temperatures over 40C. Paris recorded 40.9C in the heatwave, a record for the capital. At least 50 people died from drownings in France while trying to cool off and at least four young children were tragically killed by heat in two separate incidents in cars.

Italy’s health ministry placed 16 cities – including Florence, Milan, Rome, Turin and Verona - on its highest heat alert.

Meanwhile, in London a meeting titled Extreme Heat scheduled as part of London Climate Week was cancelled because it was just too hot.

While temperatures in Irish cities escaped the worst of that, nevertheless they broiled for days. The homeless were highlighted in Cork as at particular risk with increased risk of heat stress, dehydration and sunburn. Additional risks compound the heat - with alcohol or drug use increasing risk of heat stress and dehydration.

Heat is no longer a future climate risk. It is already here - aggravated by fossil-fuelled warming, warm oceans, dry soils, slow-moving high pressure systems and El Niño conditions that are yet another push to climate extremes.

There is no doubt heat kills – by dehydration, strain on the heart, kidneys and lungs. It can aggravate mental health and increase stress. Most at risk are older people, babies, people with chronic illness, outdoor workers and those living alone. Overheated bedrooms in homes, residential care homes and hospitals are linked to increased risk.

Heatwaves are a test of housing, healthcare, infrastructure and public protection, and many European cities are not built for them. Temperatures of up to 25C at night allow no opportunity for people to recover from heat stress experienced throughout the day.

How many heat-related deaths are we going to consider as normal before we introduce comprehensive measures that allow us to adapt to living in a city that is broiling during the day and tropically hot at night?

One city has taken up the challenge. On June 26, Mayor of London Sadiq Khan acknowledged that extreme temperatures are no longer a future threat but a clear and present danger, as he launched London’s first ever Heat Plan. The initiative was promoted as “a city-wide plan to adapt our capital, protect communities and build a climate resilient city”.

London is more exposed to heat risk than anywhere else in the UK, with temperatures reaching a new record in May of 35.1C. Its Heat Plan requires new homes to be designed to stay cooler in hot weather, using measures such as shading, ventilation and smarter design, helping curb the need for energy intensive cooling. Addressing overheating in London’s existing homes is recognised as a key priority that will require coordinated action to keep city dwellers safe and comfortable as temperatures rise.

What does a Heat Plan look like?

• More cooling spaces and access to public drinking water - such as the newly developed Marina in Cork that allows for socialisation and physical activity in well-shaded green space.
• Retrofitting homes at the highest risk of overheating. To date, retrofitting in Ireland has focused on insulation and heat retention. But providing respite from heat in summer months also needs to be addressed.
• More safe access to blue spaces such as swimming and other activities around waterways. Open air pools in Cork city would bring much-needed economic, social and community, as well as health and wellbeing benefits – giving people an opportunity to cool off without the need to escape to overcrowded beaches.
• Helping heath and care systems better withstand high temperatures. With an increasingly ageing population, acute and long stay healthcare and residential facilities must be designed to withstand temperatures of up to 40C that are increasingly likely, even on this previously temperate island on the edge of Europe.
• Making transport infrastructure as reliable and safe as operationally feasible in high temperatures. Anyone who has travelled on buses and inter-city trains during a heatwave knows how intolerably hot this experience can be.

Khan has emphasised that adapting to hotter temperatures is also a matter of social justice. People living in poorly designed homes, those without access to green space, older people, young children and those with physical or mental health conditions are often most vulnerable to heatwaves and its impacts.

His Heat Plan is an excellent template, setting a benchmark for cities across Europe to respond to and adapt to a warming climate.

To date, Cork and other Irish cities have escaped the gruelling temperatures of the UK and Europe. But the threat of spiralling heat in our cities is one that we cannot ignore.