RELEASE: New Global Platform Maps Urban Heat Risks Block by Block—and Shows Cities How to Cool Them

RELEASE: New Global Platform Maps Urban Heat Risks Block by Block-and Shows Cities How to Cool Them

March 17, 2026

Press Release

Cities Asia Africa Latin America Oceania North America Europe

Starting in over 25 cities across five continents, Cool Cities Lab maps heat down to the block level and helps cities identify the most effective solutions to lower temperatures and protect communities.

Washington, D.C. (March 18, 2026) - WRI Ross Center for Sustainable Cities today launched Cool Cities Lab, a first-of-its-kind global data platform that maps - down to individual city blocks and streets - where residents face the highest heat risk and which solutions can lower temperatures most effectively. The tool provides cities with detailed, actionable data to help guide heat planning, infrastructure investment and climate resilience strategies.

This free, open-source platform currently includes data for over 25 cities across five continents, including Jakarta, Boston, Nairobi, London, Rio de Janeiro, Mexico City and more, with additional cities planned.

Extreme heat is already straining cities worldwide, contributing to an estimated 489,000 deaths each year while driving up hospital visits and disrupting work and economic activity. The threat is intensifying: 2023, 2024 and 2025 were the three hottest years ever recorded globally. Yet most governments lack the granular data needed to plan effective local heat responses and target strategic infrastructure investments.

"Cities can't afford to treat heat as a future problem - it's already reshaping daily life and putting people in danger," said Rogier van den Berg, Global Director for WRI Ross Center for Sustainable Cities. "Actionable data is essential for responding to this growing threat. It shows where risks are greatest and helps leaders direct solutions to the communities that need them most."

Cool Cities Lab addresses critical data gaps that cities face when planning responses to extreme urban heat. The platform, co-developed with city decisionmakers, allows users to model how measures such as trees, shade structures and cool roofs could reduce heat stress and air temperatures in nearby areas. Because Cool Cities Lab is built on globally available open data, the platform can scale to cities worldwide. It enables city leaders to test different infrastructure scenarios, prioritize the most effective interventions and make an evidence-based case for investments in cooling solutions.

The platform reveals how heat exposure varies within cities and which communities face the greatest risks - often low-income and densely built neighborhoods with the least access to green space. By combining heat data with information on population and the built environment, Cool Cities Lab empowers planners and leaders to prioritize the needs of the most vulnerable people in their resilience planning efforts from the neighborhood to the entire city-and design context-specific, effective solutions.

Early applications of Cool Cities Lab data show how targeted interventions can deliver significant benefits:

• In Campinas, Brazil, increasing street trees by just 20% in a residential neighborhood could lower felt temperatures by 1.7-8 degrees C (3.1-11.4 degrees F), transforming heat-exposed routes into cooler, more walkable corridors for residents.
• In Cape Town's central business district, combining street trees with reflective rooftops could nearly double the cooling that people experience compared to using either measure alone.
• In Hermosillo, Mexico, officials have already used the data to design a new park in one of the city's hottest, least shaded areas, creating a cooler refuge for residents with few places to escape the heat.
• In Atlanta, data on the heat-mitigation potential of reflective roofs helped spur the city's 2025 Cool Roof Ordinance. The policy, informed by Cool Cities Lab data from WRI and technical assistance from the Smart Surfaces Coalition, is expected to lower citywide temperatures by 1.4 degrees C (2.4 degrees F), and cool the city's hottest and most vulnerable neighborhoods by up to 3.5 degrees C (6.3 degrees F).

To further expand adoption, WRI is collaborating with a range of initiatives supporting sub-national action on urban cooling, including the UN Environment Programme-led Cool Coalition's Beat the Heat Implementation Drive, C40 Cities' Cool Cities Accelerator and Smart Surfaces Coalition's Cities for Smart Surfaces program, to make Cool Cities Lab data, analysis and targeted support available to cities within their networks to inform their cooling strategies.

Cool Cities Lab was developed by WRI Ross Center for Sustainable Cities in partnership with WRI's Data Lab, with support from Google.org and direct input from city officials and technical experts.

To learn more about Cool Cities Lab, visit: https://coolcities.wri.org/

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Cities currently included in Cool Cities Lab include:

Buenos Aires (Argentina); Campinas, Florianópolis, Fortaleza, Recife, Rio de Janeiro and Teresina (Brazil); Addis Ababa (Ethiopia); Bhopal, Gwalior, Indore, Jabalpur (India); Jakarta (Indonesia); Kisumu and Nairobi (Kenya); Hermosillo, Mexico City and Monterrey (Mexico); Amsterdam (Netherlands); London (United Kingdom); Atlanta and Boston (United States); Cape Town, Durban and Johannesburg (South Africa); Barcelona (Spain).

Quotes from WRI experts and partners

"Heat risks can vary dramatically from one block to the next," said Eric Mackres, Senior Manager of Data and Tools at WRI Ross Center for Sustainable Cities. "But most decision-makers today still rely on coarse data that obscures this variation. Cool Cities Lab gives decision-makers and communities game-changing information to accelerate action."

"We have proven ways to bring temperatures down - people can feel much cooler in shaded areas, and cool roofs can reduce air temperatures across the city," said Brian Juhyuk Lee, Sustainability Lead, Google.org. "But a tree canopy on a wide boulevard, a shade structure at a bus stop and a cool roof on an apartment block solve different problems. Cool Cities Lab helps cities match the right solution to their goals and to the needs of residents."

"The launch of WRI's Cool Cities Lab is a critical step forward for fighting urban heat," said Adalberto Maluf, Vice Minister, Ministry of Environment and Climate Change of Brazil. "By equipping city leaders with the data and solutions needed to protect the most vulnerable and design smarter, more resilient urban spaces, Cool Cities Lab can support initiatives like Beat the Heat, which was announced at COP30 in Belém and co-led by the Brazil COP30 presidency. This will help turn ambition into action, accelerate sustainable cooling solutions that save lives, reduce emissions and build a more equitable future for our cities."

"Cities are where extreme heat hits hardest, and Cool Cities Lab gives them the critical data they need to act," said Dr. Eleni (Lenio) Myrivili, Global Chief Heat Officer, UN Habitat and UN Environment Programme & Senior Fellow, Atlantic Council's Climate Resilience Center. "Already, more than a dozen Beat the Heat local governments have asked for early access to the tool, and many more are coming. We look forward to working with WRI to help cities turn insight into action, cool neighborhoods and protect lives."

"With Cool Cities Lab, we can model the gains from trees, shade structures and reflective roofs and layer that with data on vulnerability," said Albert Ferreira, Manager: Resilience and Climate Change and Chief Heat Officer for the City of Cape Town. "This helps us pinpoint where risks intersect. It shows where people face both the most intense heat and the fewest resources to cope, so we can target solutions where they matter most."

"The data products from Cool Cities Lab played an essential role in the recent passage of Atlanta's leading cool roof ordinance," said Bill Updike, Director of U.S. Policy & Programs, Smart Surfaces Coalition. "Some of the city councilmembers were asking reasonable questions about the potential impacts of the legislation that simply could not have been answered, and certainly not so quickly, if we had not done advanced high-resolution modeling, and if we didn't have access to the analysis and data from our partnership with WRI's Cool Cities Lab team. With Cool Cities Lab many more cities now have access to the information they need to prioritize and implement actions to cool their cities, as Atlanta has done."

About World Resources Institute (WRI)

WRI works to improve people's lives, protect and restore nature and stabilize the climate. As an independent research organization, we leverage our data, expertise and global reach to influence policy and catalyze change across systems like food, land and water; energy; and cities. Our 2,000+ staff work on the ground in more than a dozen focus countries and with partners in over 50 nations.

About WRI Ross Center for Sustainable Cities

WRI Ross Center for Sustainable Cities is World Resources Institute's program dedicated to shaping a future where cities work better for everyone. Together with partners around the world, we help create resilient, inclusive, low-carbon places that are better for people and the planet. Our network of more than 500 experts working from Brazil, China, Colombia, Ethiopia, India, Indonesia, Kenya, the Netherlands, Mexico, Türkiye and the United States combines research excellence with on-the-ground impact to make cities around the world better places to live. More information at wri.org/cities or on social @WRIRossCities.

About Google.org

Google.org's mission is to unlock the potential for everyone, everywhere. Beyond traditional philanthropy, we apply Google's innovation, research, and resources to promote progress and expand opportunity for everyone.