Rudiger Ahrend
Head Of Division, OECD
Claudia Baranzelli
Programme Manager, OECD
Alexandre Banquet
Data Scientist, OECD
Temperatures around the world have been increasing in recent years, with 2023 being one of the hottest years ever recorded.*
The OECD’s 2024 ‘Regions and Cities at a Glance’ report finds that in OECD large regions, air temperatures rose by an average of 1.4°C in 2023 compared to 1981–2010. This average masks even sharper increases in polar and cold regions, where temperatures rose nearly 2°C. This trend is set to continue, as temperatures by 2050 are expected to increase by at least 3°C in cold regions and by at least 1.3°C in arid and tropical regions.
Urban heat intensifies disparities
Cities are particularly affected by rising temperatures due to the urban heat island effect. Cities’ high building density, intensive levels of human and industrial activity, artificial surfaces and limited vegetation result in higher temperatures compared to more rural areas. In the past five years, almost half of OECD cities witnessed a summer daytime heat island effect of over 3°C.
Heightened heat levels will harm health, especially for older people. It will also disproportionately affect low-income communities, which tend to have fewer green areas and higher building density and typically have fewer means to access cool spaces.
Through innovative and collaborative
policies, cities can thrive in a hotter future.
Cool hacks for hot cities
Cities’ commitment to strengthening their climate resilience has become ever more critical. Yet, local governments and city planners can act on different levels to devise locally achievable solutions to mitigate and adapt to heat island effects. Electrification and improvement of public transport can help reduce the need for private transport, as well as the heat and pollutants emitted from fuel-powered vehicles in dense urban areas. Urban spaces must also be redesigned to reduce heat exposure, especially in low-income areas.
Chilling the urban heat
Creating parks, promoting green roofs, using cooling materials, planting tree-lined streets and enacting zoning for ventilated, shaded spaces all help lower land surface temperatures. These policies must be guided by local knowledge to be effective, as each municipality experiences heat differently. Each city has a unique combination of needs and opportunities to address urban overheating.
Local governments should collaborate and learn from each other on how best to make their cities more resilient to high temperatures. Through innovative and collaborative policies, cities can thrive in a hotter future.
For more on local climate action, read “OECD Regions and Cities at a Glance 2024.”
