Quantifying Uncertainty of Ensemble Transport and Dispersion Simulations Using HYSPLIT
Abstract
Uncertainty associated with determining the source location of nuclear pollutants in the atmosphere after a nuclear fallout using a numerical model is difficult to determine. Uncertainty can originate from input data (meteorological and emissions), internal model error, physics parameterizations, and stochastic processes. This study uses the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model with data from the 1983 Cross Appalachian Tracer Experiment (CAPTEX) (Ferber et al. 1986) and simulating six nuclear detonations (Rolph et al. 2014) to quantify and communicate uncertainty in ensemble dispersion simulations. This is accomplished by utilizing an ensemble of forward trajectory simulations varying initial conditions and physical parameterizations (e.g. turbulence, boundary layer stability and mixed layer depth). The model rank for each simulation is calculated using ground measurements. This value is compared against the observed rank from the CAPTEX experiment to measure the sensitivity of each model run. Effectively quantifying and communicating uncertainty is crucial in providing probabilistic results in nuclear monitoring.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 21, 2019
- Accession Number
- AD1076343
Entities
People
- Daniel W. Bazemore
Organizations
- Air Force Institute of Technology