WRI Launches Cool Cities Lab to Map Heat Risks Across Mexico

Mexico’s rising exposure to extreme heat is increasing climate, health, and infrastructure risks in major urban centers, prompting governments to integrate thermal data into adaptation and urban planning. WRI’s Cool Cities Lab is supporting Mexico City, Monterrey, and Hermosillo in identifying heat-risk areas and prioritizing green infrastructure, tree planting, and cooling measures, with implications for public health, construction, urban development, transportation, and productivity. As El Niño and long-term warming increase heat risks, data-driven adaptation is becoming increasingly relevant to Mexico’s climate policy and municipal investment planning.

The World Resources Institute Mexico (WRI) has launched Cool Cities Lab, a public-access climate analysis platform designed to assess cities’ thermal resilience and identify the cooling potential of different urban adaptation solutions at both neighborhood and citywide scales. 

Cool Cities Lab is funded by Google.org and developed as part of the Data for Cool Cities project. It seeks to generate high-resolution thermal comfort data to inform decision-making and maximize the impact of climate adaptation solutions through the Universal Thermal Climate Index (UTCI), which estimates how people experience heat in public spaces. The index complements other forms of temperature measurement by providing a more comprehensive perspective on the human experience of heat in cities.

The project is currently being implemented in 25 cities worldwide. In Mexico, the platform is available for Mexico City, Monterrey, and Hermosillo.

Hermosillo

The first in-person Cool Cities Lab session was held in Hermosillo, bringing together representatives from the municipal government, specialists, and civil society organizations. The session aimed to introduce the platform, explore how its data could be used and collaboratively develop an adaptation agenda to address extreme heat in Hermosillo.

The tool allows users to analyze extreme heat conditions across the city at street level. This information can help identify areas where high temperatures have the greatest impact on residents and inform decisions on where to add green areas, improve public spaces, plant trees, and establish cooling shelters. In Hermosillo, the platform’s data show that more than half of the city has less than 10% vegetation coverage, while in the hottest areas, perceived temperatures can reach as high as 62°C.

Based on this diagnosis, the municipality is developing specific adaptation projects, including the construction of Cárcamo Norte Park to expand the availability of green spaces in the most affected areas, the introduction of trees in peripheral neighborhoods, the establishment of a native plant nursery to scale up reforestation efforts, and the identification of pedestrian and transportation routes where shade and cooling shelters are most urgently needed.

Mariana Campos, Interim Director of the Cities Program, WRI, sats that Cool Cities Lab is designed to be useful to a wide range of stakeholders, from public officials to community organizations, and that its value lies precisely in enabling climate adaptation discussions to be grounded in concrete, localized data. “Extreme heat has generated genuine interest among Hermosillo residents in understanding its impacts and the urgency of addressing them. We hope Cool Cities Lab can continue to serve as a useful tool for generating evidence across different sectors and territories, and that this information can provide greater clarity on where the challenges are and how to promote actions with a more significant impact,” she says.

Pablo Lazo, Global Director of Urban Development, WRI, highlighted Hermosillo’s role within the global network of cities participating in Cool Cities Lab and said that the experiences and lessons generated in the city could be useful to other cities facing similar challenges. “Hermosillo is one of the 25 pilot cities for Cool Cities Lab worldwide and has very particular characteristics because of its high temperatures. What is done here, the solutions that are tested and the lessons that are generated can help other cities that are also looking for ways to better adapt to extreme heat,” he adds.

Monterrey

Representatives from academic institutions, specialized organizations and government agencies participated in the presentation in Monterrey as part of a collaborative exercise to develop proposals to address the effects of extreme heat in the city. The Government of Monterrey says the incorporation of Cool Cities Lab is part of a sustainable urban planning strategy focused on anticipating the effects of climate change through actions that contribute to environmental protection, public health, and improvements to urban infrastructure. The platform is expected to strengthen coordination among government, academia, and civil society, promoting integrated solutions to increase the city’s resilience to climate-related events.

Monterrey faces a growing urban heat problem associated both with the region’s high temperatures and with the expansion of impervious surfaces and loss of vegetation. A WRI analysis indicates that the metropolitan area has increased its impervious surface as the urban footprint has expanded, while the loss of permeable soil and vegetation has increased residents’ exposure to urban heat islands. In this context, the Government of Monterrey has identified the expansion of green areas, tree planting, and the creation of green corridors as measures to reduce the impact of heat and improve public spaces.

Among the actions already underway is the Bosques Ciudadanos (Citizen Forests) program, promoted by the Government of Nuevo Leon to bring green infrastructure to corridors and urban areas with a high concentration of concrete. The program has intervened along avenues including Gonzalitos, Morones Prieto, and Constitucion, with the aim of reducing urban heat islands and improving the urban environment. At the municipal level, Monterrey also maintains reforestation and native-species adoption programs, including a tree-planting strategy focused on areas with a greater presence of heat islands.

Urban planning also includes longer-term solutions. The Monterrey 2040 Strategic Plan proposes the naturalization of urban spaces and intensive reforestation of public areas, as well as specific strategies for preventing, mitigating and adapting to extreme heat. Measures under consideration include incorporating green infrastructure, updating building standards and strengthening spaces designed to reduce urban heat islands.

Mexico City

Last week, the Mexico City Ministry of Environment (SEDEMA) and WRI held the workshop “Urban Climate Action Lab: Extreme Heat” to introduce the platform and strengthen public officials’ capacity to use and interpret data on exposure and risk related to this phenomenon. About 35 representatives from SEDEMA, Mexico City government agencies and borough governments participated in the activity. Through practical exercises, participants identified priority areas for action and evaluated territorial intervention strategies under an integrated risk management and intersectional approach, with the aim of translating evidence into actions to strengthen climate adaptation and resilience.

Ana Mendívil, Director of Climate Change, SEDEMA, highlights that extreme heat has become one of the main climate risks facing Mexico City, with significant impacts on public health and well-being, biodiversity and productivity, work, and public services. She says that generating data and evidence helps guide decision-making processes and the design of more effective adaptation and resilience measures to protect people, ecosystems and livelihoods over the long term.

Extreme heat has been incorporated into urban climate policy planning through the design of the Mexico City Climate Action Program (PACCM) 2025-2030, says Mendívil. Its diagnostic section indicates that the capital could face temperature increases of more than 2°C under different climate scenarios by mid-century, while the city already experiences an urban heat island effect that can increase temperatures by up to 5°C in highly urbanized areas.

“The Climate Action Program is a collaborative roadmap to address extreme heat from the perspectives of prevention and climate justice, through nature-based solutions, territorial planning, the energy transition, a culture of prevention and community risk management,” says Mendívil.

Ana Iris Enríquez, Senior Urban Development Coordinator, WRI Mexico, says the workshop sought to generate practical and actionable results based on evidence from Cool Cities Lab, helping guide urban planning decisions and advance a common climate adaptation agenda in Mexico City.

As a pilot example, Uriel Martínez, Head of the Environmental Prevention and Impact Unit, Government of Iztapalapa, explains that the borough faces a very high level of climate vulnerability due to its high population density, concentration of informal and outdoor economic activities, and lack of green spaces, all of which increase exposure to extreme heat.

Participants identified priority intervention areas in the borough based on groups requiring particular attention, including children, older adults, and female-headed households, as well as exposed systems such as public transportation and healthcare. Based on the use of geographic data, participants proposed the design of sector-specific public policies to strengthen urban resilience across the capital.

Julia Álvarez, Minister at SEDEMA, says extreme heat represents a growing challenge for Mexico City. She explains that between March and June, a large portion of the capital’s territory falls within medium- or high-hazard levels: seven boroughs face medium risk and nine face high risk, together accounting for 68% of the city’s population, with maximum temperatures ranging from 34°C to 37.5°C.

Francisco Barnés, Executive Director, WRI Mexico, highlights that temperature anomalies have increased significantly in many Mexican cities. These impacts, he says, are unevenly distributed across the population, not only because of differences in the vulnerability of various groups, but also because of how temperatures are distributed within cities.

Growing Climate and Public Health Challenge

According to researchers at UNAM, the risk of extreme heat could increase in the coming years amid the possible development of a moderate-to-strong, and potentially historic, El Niño event during 2026-2027. Francisco Estrada, Coordinator of the Climate Change Research Program, UNAM, warns that the interaction between El Niño and an already warmer planet could temporarily push global temperatures to nearly 1.8°C above pre-industrial levels. Global warming is also altering the traditional patterns associated with the El Niño-Southern Oscillation (ENSO), meaning its effects could occur with greater intensity or in regions different from those historically expected.

The impact of heat extends beyond urban comfort. The World Health Organization (WHO) estimates that approximately 489,000 heat-related deaths occurred worldwide each year between 2000 and 2019, while heat-related mortality among people over 65 increased by approximately 85% between 2000-2004 and 2017-2021. Extreme heat can worsen cardiovascular disease, diabetes, asthma and mental health disorders, while also increasing the risk of accidents and reducing labor productivity. According to WHO, many of these impacts can be prevented through heat-health warning systems, heat action plans and adaptation measures that reduce population exposure.

As extreme heat becomes a more prominent risk for cities, tools such as Cool Cities Lab can help translate climate data into more targeted urban interventions, supporting decisions on where adaptation measures can have the greatest impact.