Development of a fine scale smoke dispersion modeling system: Part IIóCase study of a prescribed burn in the New Jersey Pine Barrens
As part of achieving this goal, the Advanced Regional Prediction System (ARPS) atmospheric model has been modified to allow simulation of flow through a multi-layer canopy. The effects of vegetation elements (e.g., branches, leaves) on drag, turbulence production/dissipation, and the surface energy budget are accounted for through modifications to the ARPS model equations. Three-dimensional vegetation density data obtained from LIDAR measurements are used to initialize the canopy model. To account for the first order effects of a wildland fire, upward sensible heat fluxes are imposed within a fixed area of the model domain, with fire intensity derived from observed data. As a final step in the development process, ARPS has been coupled to the Pacific Northwest National Laboratory (PNNL) Integrated Lagrangian Transport (PILT) model.
This paper presents results from a recent modeling case study of a March 2011 prescribed burn in the New Jersey Pine Barrens. To accurately represent regional and local forcing within the region of the burn, a series of one-way nested simulations are executed, spanning from 9-km to 100-m horizontal grid spacing. Momentum, scalar, and turbulence fields are compared between the innermost domain simulation and data obtained from a series of flux towers located inside and outside of the burn unit. This work is one part of a coordinated effort to evaluate the performance of atmospheric dispersion modeling systems; papers detailing data analysis efforts as well as smoke dispersion modeling will be presented elsewhere at the conference.