According to the National Centers for Environmental Information, the ten warmest years in the 174-year record period have all occurred during the last decade (NCEI, 2023, link) with 2023 being the warmest year on record with temperatures at 1.450C above the pre-industrial baseline (WMO, 2024, link). 

We are living through an uninterrupted spell of heatwaves over the past years with the result that “heatwaves” has now entered our lexicon of hazards. They are affecting all countries with adverse socio-economic impacts, undermining lives and livelihoods while adversely affecting public health, economic productivity, and water availability and causing more incidences of wildfires and heat strokes. 

Over 350 cities across the globe, home to over 200 million people and accounting for 14% of the global urban population, are already vulnerable to extreme heat conditions. It is estimated that by 2050, over 1.6 billion people living in more than 970 cities will face regular, extreme heatwaves, which is equivalent to 40% of today’s total urban population (C40 et al., 2023, link).

The surface temperature in cities is often 10-150C higher than in the rural surroundings. This phenomenon is called the “urban heat island effect”. Poor, marginalized, and vulnerable population groups in cities, like children, elderly, persons with disabilities, people experiencing homelessness, outdoor workers, low-income households etc., are at higher risk to suffer from heatwaves and the heat island effect. A study by UNICEF indicates that while already 560 million children are exposed to frequent heatwaves, by 2050 over 2 billion children will be affected (UNICEF, 2022, link). In the US heatwaves lead to a higher mortality rate than those from hurricanes, tornadoes, and floods combined (Adams-Fuller, 2023, link). 

At the United Nations Development Programme (UNDP), we’re committed to prevent, prepare for, and mitigate the impacts from heatwaves and the urban heat island effect in developing country cities. Our interventions focus on resilience and risk management (see here UNDP’s Urban Risk Management and Resilience Strategy), and we collaborate closely with national counterparts and city authorities, international and regional organizations as well as technical and research institutions to identify and implement contextual solutions.

One of our most promising focus areas is harnessing the potential of digital technologies and innovation to address heatwaves, being spearheaded under our “Application of digital technologies to enhance heatwave resilience”. The approach seeks to complement traditional risk reduction and management measures with environment management and nature conservation efforts with application of digital technologies to provide timely alerts, advisories, and community-centric mitigation measures. The rationale behind this approach is that heatwaves and the heat island effect pose a risk to people that requires community-led initiatives to identify and implement contextual solutions.

One of the concrete activities implemented together with our national and local partners as part of this approach is the upcoming “Beat the Heat” Campaign, which revolves around the theme “Our City - Our Action”. It aims at mobilizing communities to identify and implement heatwave solutions with a focus on children, elderly, and vulnerable segments of urban populations. The campaign promotes an all-hands-on-deck approach to #BeatTheHeat and is an opportunity to build a culture of joined up action by involving schools, community organizations, businesses, and common people for putting into action contextual solutions to reduce heatwaves and the heat island effect.

Some of the identified community-led measures include:

1. Launching a mobile app to provide heat alerts, advisories to mitigate impact, and the routes to avoid or take with potential benefit to entire city population and visitors.
2. Creating green canopies and planting all-weather trees around schools, hospitals, markets, public places like markets, bus stops etc. with potential long-term benefit to local communities and contribution in the fight against climate change.
3. Setting-up water coolers near heatwave hotspots, which are operated and maintained by local communities and businesses.
4. Establishing cooling centers.
5. Harnessing the outreach potential offered by digital technology and social media to connect people to communicate about heatwave hotspots and to share effective risk reduction and mitigation measures targeting vulnerable populations and spots such as schools, hospitals, rail and bus terminals, marketplaces etc.

UNDP is interested in your feedback. Please tell us how your city addresses extreme heat and what action you and your communities take by writing to us at Ronald.jackson@undp.org and Rajeev.issar@undp.org.

Let’s join hands to #BeatTheHeat.