12.2
LARGE-EDDY SIMULATION OF TRACER FOOTPRINTS FROM INFINITE CROSSWIND LINE SOURCES INSIDE A FOREST CANOPY

Hong-Bing Su, Univ. of Georgia, Griffin, GA; and M. Y. Leclerc

Numerical tracer experiments have been carried out to study tracer concentration and flux footprint behavior within a forest canopy. Multiple tracers were released from corresponding line sources at varying heights inside the model forest. The diffusion of the passive tracers were driven by the turbulent velocities computed by a large-eddy simulation (LES) of neutrally stratified flow within and above a sparse forest canopy. The results are compared with a Lagrangian stochastic diffusion model driven by the turbulent statistics of the same velocity field generated by the LES. The similarities and differences in footprint properties as modeled by the two approaches are examined. The limitations of the LES analysis will also be discussed.

The 23rd Conference on Agricultural and Forest Meteorology