A study conducted by the International Institute for Environment and Development (IIED) based in the UK has revealed a significant increase in the number of days reaching temperatures of at least 35°C in 20 of the world’s most populated capital cities over the past three decades. Cities such as Paris, Dhaka, London, Cairo, Manila, and Kinshasa, collectively home to 300 million people, have experienced a 52% rise in these extreme heat days from 1994 to 2023.
The data shows a steady increase in days exceeding 35°C every decade: 4,755 days from 1994 to 2003, 5,343 days from 2004 to 2013, and 6,488 days from 2014 to 2023. This trend highlights the accelerating impact of climate change, exacerbated by the urban heat island effect in densely populated areas.
Several capitals, including Delhi, Dhaka, and Manila, have already suffered deadly heatwaves this year, resulting in numerous heat-related fatalities. Tucker Landesman, a senior researcher at IIED, emphasized that climate change is not just a future threat but a current reality that is intensifying. He noted the alarming rise in heat stress affecting millions and its profound implications for public health.
This study underscores the urgent need for global climate action to mitigate further temperature rises and protect vulnerable populations from the escalating impacts of extreme heat.
