SULFUR-DIOXIDE PLUME DISPERSION AND SUBSEQUENT ABSORPTION BY CONIFEROUS FORESTS - FIELD-MEASUREMENTS AND MODEL-CALCULATIONS

A Forest SO2 Absorption Model (ForSAM) was developed to simulate (1) S O2 plume dispersion from an emission source, (2) subsequent SO2 absorp tion by coniferous forests growing downwind from the source. There are three modules: (1) a buoyancy module, (2) a dispersion module, and (3 ) a foliar absorption module. These modules were used to calculate hou rly above-canopy SO2 concentrations and in-canopy deposition velocitie s, as well as daily amounts of SO2 absorbed by the forest canopy for d ownwind distances to 42 km. Model performance testing was done with me teorological data (including ambient SO2 concentrations) collected at various locations downwind from a coal-burning power generator at Gran d Lake in central New Brunswick, Canada. Annual SO2 emissions from thi s facility amounted to about 30,000 tonnes. Calculated SO2 concentrati ons were similar to those obtained in the field. Calculated SO2 deposi tion velocities generally agreed with published values.