By Minni Sastry, Advisor, Extreme Heat & Sustainable Cooling, Climate Change Division, United Nations Environment Programme (UNEP) India

“Extreme heat amplifies inequality, inflames food insecurity, and pushes people further into poverty. We must respond by massively increasing access to low-carbon cooling; expanding passive cooling, such as natural solutions and urban design; and cleaning up cooling technologies while boosting their efficiency. UNEP [Global Cooling Watch] estimates that, together, these measures could protect 3.5 billion people by 2050, while slashing emissions and saving consumers $1 trillion a year”.

UN Secretary-General Antonio Guterres, July 2024, Launch of Extreme Heat Call to Action (unsg_call_to_action_on_extreme_heat_for_release.pdf)

According to the UNEP Cool Coalition’s Global Cooling Watch report, (Global Cooling Watch 2023 | UNEP – UN Environment Programme) investing in the triple strategy of passive cooling (nature, climate sensitive urban design, reflective surfaces and smart buildings), improved energy efficiency of buildings and cooling equipment and phase-out of climate- warming gases used in cooling equipment – in line with the Global Cooling Pledge at COP 28 will reduce cooling emissions by 60% while enabling billions to be protected from the impacts of extreme heat

Cities and subnational governments globally are critical to this effort. An opportunity for cities to act towards extreme heat and sustainable cooling exists through becoming signatories for the subnational Global Cooling Pledge.

In this Pledge, subnational governments commit to develop a heat action plan by 2026, increase the area and quality of green and blue spaces in urban areas for cooling, and pursue public procurement of low-global warming potential and high-efficiency cooling technologies by 2030. All these actions help cities to adapt and mitigate extreme heat. This Pledge is a strong signal of a city’s commitment and could potentially unlock access to greater technical assistance if required to help deliver on the commitment.

UNEP is implementing a global program to help regions, countries, and cities “Be Cool” in the face of extreme heat. The program focuses on adaptive thermal comfort and passive cooling approaches in buildings and at the urban-scale and is currently supporting India, ASEAN countries, Vietnam, Cambodia, Cote d’Ivoire, and Brazil in these efforts.

India is one of the most at-risk countries in the world from rising temperatures and increasing extreme heat due to climate change. The vulnerabilities are aggravated in urban areas due to the urban heat island effect, lack of outdoor shading and nature, homes that are not heat-proof and lack of equal access to cooling equipment.

Nature has the power to cool down cities. Development authorities, policy makers, financial institutions need to work together to bring nature back into cities as critical adaptation to rising heat. Urban Heat Island assessment studies are providing the scientific justification that neighbourhoods in a city with denser vegetation, reflective surfaces and shading have the potential to be 5–7 °C cooler than the hot spots of the city. Similarly, buildings with passive cooling (shading, cool roofs, cross-ventilation, insulation) have the potential to maintain cooler and thermally comfortable spaces indoors. Passive cooling in buildings and urban spaces needs to become the norm and increasingly mandatory in order to prepare cities for the coming heat extremes.

Disclaimer: The views expressed in this piece are those of the author/s and do not necessarily reflect the views or policies of AIDMI.