Welcome to the Zurich Heat Relief Map

This interactive map is a research project designed to help residents and visitors of Zurich identify areas of potential heat stress (Urban Heat Islands) and locate nearby points and zones of relief during hot weather. Our goal is to provide accessible information, especially for vulnerable populations, to promote well-being and safety during heatwaves.

Navigate using the menu above to explore the interactive map, understand the science behind urban heat, learn about our data sources, and discover key findings from our research.

High Temperature Warning! Seek relief.






Background

Urban Heat Islands (UHIs) represent a significant public health challenge, particularly as global temperatures rise. These are metropolitan areas that experience markedly higher temperatures than their surrounding rural counterparts due to human activities and modifications to the land surface, such as heat-absorbing buildings and pavements, and a lack of green spaces. This sustained elevation in ambient temperature, especially during heatwaves and with reduced nighttime cooling, can lead to a range of adverse health outcomes. These include direct heat-related illnesses like heat exhaustion and life-threatening heatstroke, as well as the exacerbation of pre-existing chronic conditions such as cardiovascular, respiratory, and kidney diseases. Vulnerable populations, including the elderly, young children, individuals with chronic health issues, and those with limited access to cooling, bear a disproportionate burden of these health impacts (Heaviside et al., 2017).

The challenge is compounded by global climate change, which is projected to further increase average temperatures and the frequency of heatwaves. For instance, according to MeteoSchweiz (2018), Switzerland can expect an average annual temperature increase of up to 3°C by 2060 if greenhouse gas emissions continue to rise. In urban areas like Zurich, the combination of rising global temperatures and localized heat intensification due to the UHI effect presents a serious threat. The City of Zurich's Health and Environment Department notes that densely built-up and sealed areas heat up more intensely than natural landscapes, leading to these "Wärmeinseln" (heat islands). In hot summer nights, central areas of Zurich can be up to 7°C warmer than the urban periphery, and in the warmest nights, temperatures in dense areas may not drop below 24°C (Stadt Zürich, 2025). This impaired nighttime cooling is particularly problematic and impacts the sustainability and inclusivity of urban environments, a core aspect of UN Sustainable Development Goal 11,Sustainable Cities and Communities (United Nations).

UN Sustainability Goals Logo

Recognizing this critical issue, our research project, the "Zurich Heat Relief Map," aims to address the following key questions:

  • Which areas in the city of Zurich are disproportionately affected by heat (i.e., function as Heat Islands)? Identifying these zones is the first step towards targeted mitigation and public advisory (Kim, 1992)
  • Where are publicly accessible structures or areas located within Zurich that can grant relief from the heat? This involves mapping resources like parks, green spaces, public fountains, and swimming baths.
  • How can a web map be effectively designed to help users, especially vulnerable individuals, efficiently locate these relief structures and navigate to them? This question drives our focus on user-centered design, clear geovisualization, and intuitive functionality.

The City of Zurich is already taking steps to counteract urban overheating by incorporating city climate aspects into communal planning and implementing measures based on heat mitigation plans, such as the "Fachplanung Stadtbäume" (Specialist Planning for City Trees). Our project seeks to complement such efforts by providing an accessible information tool. By applying evidence-based approaches to understand and visualize urban heat and relief options, we aim to contribute to making Zurich a more equitable, comfortable, and climate-resilient environment, aligning with the broader objectives of fostering healthy lives and creating sustainable urban communities for all its inhabitants (Stadt Zürich, 2015).

UN Sustainability Goals Logo

Sources:

  • Stadt Zürich. (2025). Umweltbericht. https://www.stadt-zuerich.ch/site/umweltbericht/de/index/stadtklima.html
  • MeteoSchweiz. (2018). CH2018 - Klimaszenarien für die Schweiz. Bundesamt für Meteorologie und Klimatologie MeteoSchweiz. https://www.nccs.admin.ch/nccs/de/home/klimawandel-und-auswirkungen/schweizer-klimaszenarien.html
  • United Nations. Sustainable Development Goals. https://sdgs.un.org/goals
  • Heaviside, C., Macintyre, H., & Vardoulakis, S. (2017). The urban heat island: implications for health in a changing environment. Current environmental health reports, 4, 296-305
  • Kim, H. H. (1992). Urban heat island. International Journal of Remote Sensing, 13(12), 2319-2336.

Data Sources

  • Zurich City Boundary: Opendata Zürich.
  • Heat Island Areas: Opendata Zürich (simplified).
  • Cool Zones: Opendata Zürich (simplified).
  • Fountains: Opendata Zürich.
  • Public Baths: Official city information and OSM.
  • Street Network: OpenStreetMap via OSRM for routing.
  • Basemap Tiles: CartoDB Positron. Attribution: OSM, CARTO.
  • Live Temperature: Open-Meteo API.

Note: For this showcase, some datasets are simplified.

Design Principles, Findings & Literature

The design of the Zurich Heat Relief Map is grounded in established principles of geovisualization, Human-Computer Interaction, usability, and cartography. Our primary goal is to create a tool that is effective, efficient, and satisfactory for the general public, especially vulnerable individuals, to use for heat-related decision-making. This section summarizes our design rationale and preliminary findings, supported by relevant concepts from the field.

Guiding Design Principles:

  1. User-Centered Design & Accessibility (Nielsen, ISO 9241):

    The user is at the core of our design. We aim for high usability (effectiveness, efficiency, satisfaction) and utility (usefulness). Special consideration is given to vulnerable populations, influencing choices for color contrast (WCAG AA guidelines), font legibility, simple interactions, and clear language. The design avoids relying on color alone to convey critical information (e.g., temperature warnings include icons and text). This aligns with the idea that a "successful system must be useful, usable, and used."

  2. Clarity, Simplicity & Cognitive Load Reduction (MacEachren, Tufte):

    The interface is designed to be uncluttered, presenting information directly and minimizing cognitive load. We follow the principle that "thematic relevance should equal perceptual salience." Important information (like warnings or relief points) is made visually prominent. The map itself simplifies complex reality into an understandable model, a core concept in cartographic abstraction.

  3. Effective Visual Variables & Semiotics (Bertin, MacEachren):

    The choice of colors, icons, and symbols (our "map language") is intentional:

    • Color: Warm colors (reds/oranges) for heat islands and warnings; cool colors (blues) for relief zones. These are intuitive associations. Alarm mode dramatically shifts the palette to signal urgency.
    • Icons: Font Awesome icons provide recognizable symbols for fountains (), baths (), location (), etc., aiding rapid comprehension.
    • Shape/Form: Polygons for areas, distinct point markers for specific locations.
    These choices aim to ensure that the map's "looking" leads to "seeing" and then "understanding" (MacEachren's model of map interaction). The color choices take colorblindness into consideration.

  4. Interactivity & Engagement:

    While our map is 2D, we incorporate several levels of interactivity: static elements, subtle animations (pulsing location, route arrows), conditional display (layer toggling, temperature warnings), and direct manipulation (pan, zoom, click interactions). These empower users to explore data relevant to their needs.

  5. Professionalism & Trustworthiness (SOA - State of the Art):

    A clean design, clear typography, and reliable functionality aim to build user trust. The disclaimer manages expectations for this research project.

Specific Design Choices & Justifications:

  • Layout & Navigation: Single-page application feel with a clear, sticky navbar.
  • Color Palette: Normal Mode: Calming blues, natural greens/blues, and warning yellows/oranges. Alarm Mode: Urgent reds and oranges with high-contrast text.
  • Typography: Sans-serif fonts (Segoe UI, Arial) for legibility.
  • Map Design: Leaflet JS, CartoDB Positron basemap. Polygon layers (`interactive: false`) ensure map clicks set location, while point layers remain interactive for popups.
  • Animations: Used sparingly for feedback (pulsing location, route arrows, UI transitions).
  • Legend: Collapsible, clear symbols, and toggles.

Preliminary Findings:

A deployed tool like this could yield findings on user engagement during heatwaves, utility of pathfinding, increased awareness of heat islands and relief resources, and potential behavioral nudges towards proactive cooling.

Limitations and Future Work:

As a research prototype, this Zurich Heat Relief Map has several limitations and numerous avenues for future development. Currently, the heat island data is simulated and would require validation with real-world sensor data or more sophisticated urban climate models for operational use. The set of relief points and zones, while representative, may not be exhaustive and could be expanded through more comprehensive data collection, including community-sourced information. The routing service is external (OSRM demo) and for a production system, a dedicated, robust routing instance would be necessary, potentially incorporating more detailed pedestrian attributes like shade availability or accessibility for wheelchairs.

Future enhancements could include:

  • Personalized Risk Assessment: Allowing users to input personal sensitivity factors (e.g., age, health conditions) for more tailored warnings or route suggestions.
  • Real-time Updates: Integrating live data for fountain operational status or temporary cooling center availability.
  • Advanced Routing Options: Pathfinding that considers factors like elevation change, shaded routes, or routes avoiding high-traffic areas.
  • User Feedback Mechanisms: Incorporating tools for users to report inaccuracies or suggest new relief points.
  • Multi-language Support: Expanding accessibility to Zurich's diverse population.
  • Indoor Cooling Locations: Adding information about publicly accessible air-conditioned spaces (libraries, community centers, etc.).
  • Offline Functionality: Providing a cached version of the map and essential data for use without an active internet connection.
  • 3D Visualization Exploration: While this project is 2D, future research could explore the benefits and challenges of 3D representations for understanding urban microclimates (inspired by concepts from the slides on VR/3D).
  • Usability Testing with Target Groups: Conducting formal usability studies with vulnerable populations to refine the design and ensure maximum effectiveness.
These additions would enhance the map's utility, accuracy, and user experience, moving it closer to a comprehensive public health tool.

Sources:

This project draws upon a wide body of knowledge. Key conceptual areas include:

  • Bertin, J. (1967). Sémiologie graphique: les diagrammes. Mouton.
  • MacEachren, A. M., & Kraak, M. J. (1997). Exploratory cartographic visualization: advancing the agenda. Computers & geosciences, 23(4), 335-343.
  • Tufte, E. R., & Graves-Morris, P. R. (1983). The visual display of quantitative information (Vol. 2, No. 9). Cheshire, CT: Graphics press.
  • Nielsen, J. (1994). Usability engineering. Morgan Kaufmann.
  • ISO 9241-11 & 9241-210 (Usability and User Experience).

The design strives to create a "map that works" by being perceptually salient, cognitively efficient, and pragmatically useful for its intended audience and purpose, navigating urban heat in Zurich.

Contact

The "Zurich Heat Relief Map" is a conceptual research project. We believe in using information to help communities adapt to environmental challenges.

Get in Touch:

Email: Damien Beerli

Email: Elias Bertel