CAREER:Developing a Consensual Validation and Benchmarking Procedure for Pyroclastic Density Current (PDC) Hazard Models

University Of South Florida, Tampa FL

Investigators

Abstract

This proposal focuses on advancing the breadth and depth of understanding of the hazards associated with pyroclastic density currents (PDCs). The proposed study will focus on five overarching goals: 1) developing a general physical/sedimentological model applicable to all types of PDCs; 2) evaluate the accuracy of numerical models in representing PDC-related phenomena through community-based validation and benchmarking exercises; 3) drive future research on PDC hazard assessment (e.g., "validation" experiments, field measurements, uncertainty analysis); 4) provide a community-wide interpretation framework for volcanic flow hazard assessment studies; 5) developing quantitative skills in geoscience education and increasing awareness of the community about the potential and limits of numerical tools ("model literacy") and the complementarity of experimental (both laboratory and field based) and numerical studies. This framework will provide critical information about the uncertainties in hazard assessments that depend on these models. The drive for this knowledge stems from the limited success of current hazard assessment studies to capture the real hazard potential of such volcanic flows. The broader goals for the proposed work are: (1) bringing multi-disciplinary teams together to discuss the relationship between field studies, computational modeling and hazard assessment; (2) increasing familiarity with and limitations of computational modeling tools to both geoscience students and the broader community; and (3) tailoring the hazard assessment to the needs of the user communities. The general approach is based on an iterative process of integrating data, theories and models. In this process, the data collection (through field investigations, laboratory experiments, remote sensing, monitoring and numerical modeling) allow investigators to revisit and revise scientific theories and principles (for example, a general physical/sedimentological PDC model), which then serve as a basis for computational and experimental models (through calibration, validation, benchmarking and prediction) that can then be applied to the collected data to improve the understanding of the dynamics of PDCs, as well as their hazard assessment studies. This integrative study will follow the methodology proposed for the validation of computational fluid dynamics codes designed to simulate complex industrial and technological systems, based on a hierarchical process of comparing numerical models with experiments and observations. In addition, the Spreadsheets across the Curriculum (SSAC) educational model (https://serc.carleton.edu/sp/ssac/index.html) will be integrated into the VHub cyberinfrastructure (www.vhub.org) to: (1) enhance computational literacy in the geosciences by promoting problem-solving using a structured environment, (2) develop, share and disseminate all activities and deliverables related to model validation and benchmarking efforts that will serve as a basis to drive future research on volcanic flow hazard assessment studies. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.