Health-threatening heatwaves will become more intense due to climate change, putting millions more people at risk from dangerous summer temperatures, new research has revealed.

The analysis, released today by researchers at The University of Manchester for Friends of the Earth, identifies the areas and communities across England set to be hardest hit by extreme heat.

Communities most vulnerable to the dangerous health impacts of soaring temperatures are those with a high number of older people and children, those without green space to shelter from the heat, and those where the type of housing, such as high rise buildings and mobile homes, is most susceptible to overheating.

According to the Met Office, hot weather can place particular strain on the heart and lungs, meaning that the majority of serious illness and deaths caused by heat are respiratory and cardiovascular. Older people, those with pre-existing health conditions and young children are especially at risk.

Researchers found the top five local authorities with the most "at risk" neighborhoods are Birmingham, Newham, Tower Hamlets, Hackney and Nottingham.

The research looks at which neighborhoods (areas with an average population of 1,700) across England are most at risk of heat now and in future warming scenarios.

In all scenarios, the communities set to be most affected by global heating are those with below average carbon footprints—those less responsible for the climate crisis. The research also finds that people of color are four times more likely to live in areas at high risk of dangerous levels of heat. The key findings include:

• Even if the world stays on track to meet the global goal to limit warming to 1.5°C, more than 3,000 of the most vulnerable neighborhoods—more than six million people—will regularly be exposed to very hot weather of 27.5°C for five or more days during the summer months. If temperatures rise to 3°C, then the same areas will be regularly exposed to dangerously hot temperatures of over 30°C.
• Overall, nearly half (48%) of neighborhoods—or 28 million people—in England will be exposed to "very hot weather" at 1.5°C of warming. This increases significantly if global temperatures rise by 2°C and 3°C to affect 60% (34 million people) and 81% (46 million people) of neighborhoods, respectively.
• Global temperature rise of 3°C would put 50% of neighborhoods—or 30 million people—at risk of "dangerously hot weather" where temperatures hit 30°C or more for five or more days during summer.

Friends of the Earth is calling for the 3,000 most vulnerable neighborhoods to be prioritized for publicly-funded adaptation projects and greater efforts to reduce planet-heating greenhouse gases.

"Extreme heatwaves and health alerts like we're seeing this week will become much more frequent and severe due to climate change," said Mike Childs, head of research at Friends of the Earth. "To prevent the most dangerous scenarios becoming a reality, all countries, including the U.K., must make greater efforts to prevent runaway climate breakdown. Suggestions by some politicians that the U.K. should dial back on climate goals are short-sighted and reckless. People on the frontlines of the climate crisis in the U.K. and overseas are already being hit by its impacts, despite being the least responsible. We need governments to double-down on cutting emissions and providing funding for climate adaptation programs, such as planting street trees."

Global temperatures are already 1.1°C above pre-industrial levels. Under the Paris Agreement, governments have agreed to limit warming to 1.5°C to avoid catastrophic climate change.

According to estimates based on current climate pledges, the world is heading towards 2.4°C of warming, but these commitments are not being met. The U.K. government's advisory body, the Committee on Climate Change, estimates that only 39% of the policies in its Net Zero Strategy are credible.