What is CliMaré?

CliMaré is a research and community action project that investigates the impacts of extreme heat on the health and daily lives of people in Maré, promoting environmental education and proposing local solutions.

The research starts from problems commonly experienced in the territory, such as high temperatures, humidity, mold and poor air quality. Its aim is to understand where these problems are most severe, who is most affected and which solutions can be implemented in people's homes.

Ten young people from Maré work as climate researchers and community mobilisers. They live in different parts of the territory and have educational backgrounds in fields such as biology, natural sciences, philosophy, the arts and social work. They take part in data collection, activities with residents and the project's training programme.

CliMaré builds on Redes da Maré's work producing data on socio-environmental issues in the territory. This research and information help assess the scale of problems, guide initiatives and advocate for effective public policies.

Why is CliMaré important?

Climate change has made extreme heat an increasingly serious threat to health. A study based on data from 326 cities in nine Latin American countries found that approximately 6% of deaths in urban areas are associated with heat. The same research shows that, on days of intense heat, each 1°C increase in ambient temperature is associated with a 5.7% increase in overall mortality. The Rio de Janeiro Municipal Health Department estimates that days when temperatures reach or exceed 40°C for four hours or more are associated with a 50% increase in deaths from conditions such as hypertension, diabetes and kidney failure among older people.

In favela territories, the impacts can be even more severe. Most homes have poor ventilation and contain materials that retain heat. Green spaces are virtually non-existent, while materials such as concrete are widespread. In addition, many families live with problems of water infiltration and mold, which affect breathing and aggravate conditions such as asthma and allergies. In February 2025, when the city recorded a temperature of 44°C, measurements on the asphalt of Rua Principal, in Nova Holanda, reached 61°C, while the temperature inside the kitchen of a local business reached 82°C.

(References)

1. KEPHART, Josiah L. et al. City-level impact of extreme temperatures and mortality in Latin America. Nat Med 28, 1700–1705 (2022). https://doi.org/10.1038/s41591-022-01872-6.

2. Epidemiological Intelligence Centre, Rio de Janeiro Municipal Health Department.

CliMaré investigates the relationship between heat, thermal comfort, air quality, humidity and residents' health, taking into account the different types of housing found across Maré.

Diagnosis

The diagnostic stage brings together data from sensors, questionnaires, home visits and conversations with residents.

This information helps locate problems and assess their severity. It also shows how heat, humidity and air quality affect different groups and areas unequally.

The research is conducted with residents' participation. The agents ask questions, listen to their accounts and bring these issues back to the territory.

Intervention

Following the diagnostic stage, the project tests solutions to problems identified in homes.

The main initiative is a coating made from cement and wood sawdust, developed in the laboratory by researchers at Numats/UFRJ. The material has the potential to control humidity, reduce heat inside homes and, consequently, improve residents' well-being.

Training. Diagnosis. Intervention.

“One of CliMaré's objectives is to contribute to the training of the research agents. Moments like this broaden their learning through practical, applied experience, while also strengthening partnerships and contributing to the project's development.”

Tainá Neves, CliMaré Coordinator