Almost half the world’s major cities will be at high risk from climate hazards between now and 2050 under a continued high emissions scenario, a new report has found. The London Stock Exchange Group’s “COP29 Net Zero Atlas”, released ahead of COP29, which will get underway in Baku in just a few weeks’ time, and COP30, next year in Belém, assesses “how four key climate hazards (floods, cyclones, heatwaves, and water stress) could impact 49 of the world’s largest cities)” under high and low emissions scenarios. The cities currently generate around 20% of global GDP.
Using Sust Global analytics, the researchers project that the 440 million people living in those cities would, at the least, need to dedicate “large-scale resources” to adapt to climate risks, including developing “monitoring and early warning systems” and more resilient infrastructure.
Extreme heat days to double
At worst, under a continued high emissions scenario, the percentage of cities in the list that would face “high risk exposure” rises from 18% to 47%. The report also notes that the “average number of days of extreme heat is expected to more than double across major cities from an average of 14 to 36 days in 2050.”
The number of excess heat-related deaths around the world is already rising, while warming sits at 1.3°C. LSEG predicts that global heating will reach 2.6°C under current policies. Europe alone suffered between 44,000 and 47,690 deaths in 2023, according to European Commission data.
Some cities are already looking at cooling solutions, from increasing tree cover and green spaces which have been found to keep urban temperatures down, to creating places where locals can swim. But decarbonisation and the climate commitments due at the forthcoming COPs are paramount.
The Middle East and Southeast Asia
It is cities with large wealth disparities that are undergoing rapid development where investment is most needed, according to the Atlas. On the urgent list for transition investment, are cities “in the Middle East and Southeast Asia” the report’s authors say, “where elevated exposure to climate hazards can intersect with rapid urban expansion, high inequality, large informal settlements and limits on the provision of public services.”
Double whammy of heat waves and water stress
Six of those Middle Eastern and Southeast Asian cities are expected to experience over 50 days of extreme heat a year. And five– Singapore, Surabaya, Dubai, Riyadh and Jeddah – would have “to confront a combination of high risk for both water stress and heatwaves by 2050,” the report says.
By 2050, Australia too would be at high risk of water stress, as would Ankara and Istanbul in Türkiye, Cape Town in South Africa, Indonesia’s Jakarta, Italy’s Rome, Mexico City and Tijuana, and Spain’s capital, Madrid.
Flooding and cyclones
For cities with flooding and cyclone risks, the threat will come more often, increasing from one cyclone every sixteen years to one every decade. When it comes to flooding, Amsterdam’s already high risk goes by 60%. Japan would be hard hit by cyclones with Tokyo going “from one event in 11 years in 2024 to one in seven by 2050” while Yokohama’s risk also rises to one cyclone every six years and is ranked high by 2050. For Shanghai, an already high risk of severe cyclones would increase by a further 50%. South Korean cities also see their risk turned up to high.
The researchers note the “particularly large economic damages to cities due to their impact on real estate and infrastructure. In both New York City and Hong Kong, for example, authorities have assessed that hundreds of billion of US$ in real estate is at risk from flooding and storms.”
