UCARe4Citizen – Urban Climate in Augmented Reality for Citizens Participation

“Simulating tomorrow's urban climate in the holodeck”

Logo UCARe4C
© Fraunhofer IBP
Project logo UCARe4C.
work steps with the new urban climate model PALM-4U
© Fraunhofer IBP
Simulating the urban climate with the new urban climate model PALM-4U.

As digitization advances, new opportunities are opening up for urban planners and municipal stakeholders to visualize planning projects realistically and to discuss planning alternatives together with citizens based on a model. Digital 3D models allow building projects to be visualized from any perspective and in varying levels of detail. One advantage of this method is that structural alternatives can be developed and analyzed more quickly. Ideally, the computer model provides the means to immediately identify and evaluate the impact of planning decisions on people and the environment. New types of communication media that use augmented reality are also expected to facilitate participatory decision-making processes for urban construction projects in the future. Although a whole range of technologies, from smartphones to data glasses, are already in use today to display 3D planning data, the greatest challenge is to extract the desired information from the abundance of available data and to present results in a user-friendly manner.

Project goals

The joint project UCARe4Citizen studies the necessary conditions to simulate the effects of urban planning measures on the climate and to visualize these in augmented reality. Based on three-dimensional city and building models, as well as terrain and geo data from various sources, a so-called Urban Climate Model (UCM) is used to study the impact of urban structures or construction measures on microclimates. The model allows different climatic effects in urban areas to be depicted with a very high spatial and temporal resolution. How does an urban heat island effect occur that causes urban structures to overheat? How can cities counteract this effect in the long term with adaptive measures, such as new green spaces or bodies of water?

To answer these questions, results from an urban climate simulation must be carefully prepared so that they can also be interpreted by non-experts. Visualization techniques from the field of augmented reality (AR) and mixed reality (MR) offer a novel solution for this type of communication. Such technologies are now available on the market and are used, for example, on mobile devices such as smartphones or tablets, or in connection with special data glasses.

The immersive form of visualization allows users to grasp specific effects on people and the environment in a vivid and intuitive way.


 As a result, the actual effects of construction measures can be conveyed more directly, such as their dimensions in relation to the surrounding structures and their impact on the temperature in public spaces.

The digital technologies thus enable all planners, investors, and citizens to appreciate for themselves the sustainable quality of planned urban development projects. Simulations and their visualization also make the outcome of decisions transparent and comprehensible for citizens' initiatives, associations, and societies.

Current project status

Involved in the joint project UCARe4Citizen is an architectural office for urban planning (SBA GmbH) and experts for augmented and mixed reality solutions (Holo-Light GmbH).

At the start of the project, suitable scenarios for simulating the urban climate will be developed in several workshops together with the city partners Laupheim and Munich. Next, these scenarios will be used to examine the impact of urban development alternatives on the urban climate. The aim is to establish the necessary digital process chains as early as possible, to implement data requirements and to analyze interfaces to the urban climate model (PALM-4U).

The scenarios serve as a basis for testing and demonstrating visualization techniques that can be deployed to illustrate the climatic effects of urban structures in the future.

Relevant and mappable parameters will be then selected from the simulation and converted and optimized specifically for display in AR applications. The challenge lies in visualizing enormous volumes of climate simulation data on mobile devices (e.g. data glasses). For this purpose, the project partner Holo-Light is providing the necessary software functions and IT infrastructure.

As soon as the newly developed AR applications are available, it will be possible to test the functions of the urban climate visualization solution in real life. Pilot projects in the participating municipalities will serve to identify and, if possible, reduce the risks involved in introducing the new methods. The focus of these projects will be on addressing and solving issues regarding acceptance, economic viability, and market potential.

In addition to developing a functional technology demonstrator, a practical guide will also be compiled in the UCARe4Citizen project that contains the findings from the pilot projects and makes them available to interested experts.

The joint project is being funded by the Federal Ministry for Economic Affairs and Energy within the scope of “Development of Digital Technologies” (funding code: 01MT20004A).

Project partners

  • SBA Architecture and Urban Development GmbH
  • Holo-Light GmbH
  • City of Munich, Department of Urban Planning and Building Regulations
  • District town of Laupheim, Building Department
  • Fraunhofer Institute for Building Physics IBP