It hasn’t been a good year for people who care about climate change. A hoped-for peak in carbon emissions has failed to emerge, meaning we continue to warm the planet at an accelerating rate (see “Humanity has warmed the planet by 1.5°C since 1700”). Meanwhile, the election of Donald Trump for a second term as US president is likely to see the country retreat on climate action, with his pledge to “drill, baby, drill” for new oil and gas supplies.

Similar sentiments towards fossil fuels come from Ilham Aliyev, the president of Azerbaijan, who has called the natural resources of his oil-rich nation a “gift from God”. Aliyev made the comments at the COP29 climate summit, hosted in Azerbaijan’s capital, Baku. Ironically, this “gift” will become increasingly inaccessible as the Caspian Sea dries up in a warming world, stranding billions of dollars of fossil fuel infrastructure (see “COP29 host Azerbaijan faces climate disaster as Caspian Sea dries up”).

In light of this failure by politicians on the international stage to get to grips with the reality of climate change, other leaders need to step up – and, surprisingly, city mayors may be best placed to do so.

Adapting cities to cope with the specific effects of urban heat will be essential

While mayors can’t be expected to influence the global climate, they oversee the well-being of the more than 50 per cent of the world’s population who live in urban centres – a figure expected to grow to 70 per cent by 2050, at which point temperatures will have risen by 2.5°C under current projections. Adapting cities to cope with the specific effects of urban heat will be essential, from promoting green spaces to investing in buildings that can be cooled without air conditioning (see “Extreme heat is now making cities unlivable. How can we survive it?”).

The good news is many mayors are already aware of their responsibilities. London’s mayor, Sadiq Khan, is aiming for the city to reach net zero by 2030. Anne Hidalgo, mayor of Paris, France, has planted trees and banned cars in certain areas. And Karen Bass, mayor of Los Angeles, has promised a green transformation ahead of the city hosting the Olympics in 2028. Organisations like C40 and Climate Mayors are helping unite local politicians across the world in action. This won’t solve climate change, but it will make living in a warming world more bearable for many.