CHaRM-BE: Understanding and Managing Compound Health Risks from Environmental and Climate Stressors in Urban Belgium

The growing impact of climate change and ecosystem degradation on public health presents Belgium with new and complex challenges. The Belgian Climate Risk Assessment (BCRA) identified heat as one of the most significant health risks, while also highlighting a knowledge gap on how heat interacts with air pollution and other compounding factors.

The CHaRM-BE project (Compound Hazards, Risks, and Mitigation for health in BElgium) addresses these challenges by analysing the combined effects of temperature variations, air pollution, wind, precipitation and land use on the health of vulnerable populations and society in urban areas. The project builds on interactions between the Earth System Boundaries framework developed by the Stockholm Resilience Centre and examines climate risks from the perspective of a healthy society.

Belgian cities are increasingly confronted with prolonged periods of heat, air pollution and excessive or delayed rainfall. At present, there is still insufficient understanding of whether these factors may reinforce one another and thereby generate greater negative impacts on population health. Older adults, children, people living with chronic conditions and those in vulnerable socio-economic circumstances are at increased risk of adverse health effects resulting from climate and environmental stressors.

While the individual impacts of hazards such as heat on excess mortality are already well documented, there remains limited understanding of:

• the combined effects of multiple climate and environmental factors;
• the consequences for disease, mental well-being and mortality;
• the wider social and economic impacts on society.

CHaRM-BE addresses this knowledge gap by systematically mapping and analysing these complex interactions.

1. Quantifying compound risks: The project investigates how meteorological and environmental factors, including heat, air pollution, humidity and wind, jointly affect health outcomes. Attention is given to differences between population groups based on age, income and residential environment.
2. Assessing societal impacts: In addition to direct health effects, the project examines broader societal impacts, including absences due to illness, work incapacity and premature mortality. It also estimates the associated costs for the healthcare system and the economy, including through Disability-Adjusted Life Year (DALY) indicators.
3. Evaluating adaptation measures: The project assesses how urban interventions, such as green infrastructure, land-use modifications and architectural measures, can reduce heat exposure and pollution levels, thereby lowering health risks.
4. Anticipating future risks: By combining climate projections with trends in urbanisation and demographic change, the project evaluates how health and society may be affected in the future.
5. Supporting policy and decision-making: Based on the findings, risks and solutions will be prioritised, and guidance will be developed for policymakers and urban planners. An interactive decision-support tool will visualise different scenarios and support evidence-based policy choices.

CHaRM-BE distinguishes itself through a highly integrated and data-driven approach. The project brings together multiple data sources, including:

• Projections from high-resolution climate models including the Belgian climate scenarios (CORDEX.be II and ALARO-SURFEX);
• Health data, including Intego (the Flemish general practice registration network), hospitalisation data from the InterMutualistic Agency (IMA) dataset, and mortality statistics from Statbel;
• Socio-economic data, including income, residential environment and vulnerability indicators.

By combining these datasets, the project will establish a unique integrated database that enables advanced modelling approaches. This will improve understanding and quantification not only of health risks, but also of their broader societal and economic consequences.

The project also employs innovative analytical methods, including:

• impact chain approaches;
• time-series analyses;
• scenario modelling of adaptation measures.

A key feature of CHaRM-BE is its explicit focus on social inequality and vulnerability. Climate change does not affect all population groups equally. The project therefore analyses differences across:

• age groups;
• gender;
• socio-economic status, including migration background;
• living and housing conditions.

This approach will support the development of targeted and equitable adaptation strategies and help policymakers tailor measures to the needs of the most vulnerable groups.

CHaRM-BE is a large-scale collaborative research project led by Dr Charlotte Scheerens and Professor Gijs Van Pottelbergh from the Academic Centre for General Practice at KU Leuven. The project is carried out in partnership with:

• Meteorological and climatological research, Department of Climate Modeling and Impact Studies, the Royal Meteorological Institute of Belgium (RMI);
• Department Epidemiology and Public Health, Unit Health Information, Sciensano;
• I-BioStat, Data Science Institute, Hasselt University;
• Department of Sociology, Vrije Universiteit Brussel (VUB);
• Laboratory of climatology and topoclimatology, department of geography, Université de Liège (ULiège);
• Department Geography, Ghent University.

• climate modelling;
• public health and primary care;
• epidemiology;
• urban planning;
• socio-economic analysis.

The project is also closely aligned with the mission of CERAC, which aims to improve understanding of climate risks and translate scientific evidence into effective policy action. That is why CERAC is actively following up this project and supporting the project management and stakeholder engagement.

• Belgium’s national climate adaptation strategies;
• the further development of the Belgian Climate Risk Assessment (BCRA);
• policy development in the fields of health, urban policy and climate.

The project goes beyond traditional studies by:

• analysing risks in an integrated manner;
• quantitatively evaluating adaptation solutions;
• providing policymakers with practical tools and evidence-based guidance.

CHaRM-BE is a three-year research programme that started in March 2026.

Final results are expected in spring 2029.

The project is funded by the BELSPO Science4Policy programme and by CERAC.