Simulation tools for gravitational mass flows, such as snow avalanches, debris flows, and rock avalanches, are used for scientific applications, educational purposes and operational assessments of related natural hazards, as well as for designing protection measures. These applications have different requirements and limitations. This poses a challenge to which level of complexity should processes be described in model formulations. This decision will depend on for example the availability of information on initial and boundary conditions, computational costs, actual knowledge of involved processes, potential need for operational reliability, etc.

In this session, we invite the presentation of current developments and advances in: process understanding, flow model formulations, numerical implementations, measurement techniques, as well as analysis methods and their transfer into user-friendly simulation tools. In this context, we would like to discuss the following questions:

• What is missing and needed to integrate scientific developments into simulation tools applied in science, operations and education?
• Which factors have facilitated the integration of scientific developments into simulation tools?
• What standards and requirements exist for operational tools?
• Which level of complexity is useful and necessary for different fields of application?
• What kind of measurement data is required to test the applicability and robustness of existing simulation tools and new developments?
• How can test sites and measurement data contribute to the development of operational tools, and what are the challenges involved?