Sub-Canopy Smoke Dispersion: Measurements of fire-behavior, fuels, consumption, emissions, plume rise and dispersion near and in a prescribed fire-source

During winters 2010 and 2011 a suite of observation data were collected to characterize smoke emissions and dispersion from sub-canopy low intensity and smoldering fires. Four research burns were accomplished at The Nature Conservancy's (TNC) Calloway Forest/Sandhills Preserve in North Carolina, which were carried out to achieve TNC land management objectives. We collected data beneath the forest canopy, near and inside the fire source before, during, and after the prescribed fire. The project was designed to collect observation data at each modeling step within the BlueSky Smoke Modeling Framework (BlueSky Framework). Fire behavior, fuel loadings and moisture, consumption, emissions, plume rise, and sub-canopy dispersion of smoke were observed. Two towers outfitted with meteorological equipment measured fine-scale changes in the wind and turbulence and to characterized the thermodynamic properties of the gases released from the fire. A third tower was also equipped to measure a suite of trace gases including carbon dioxide, carbon monoxide, ozone, methane, ammonia and other trace gases. Fine particulate matter (PM2.5) was measured to determine smoke plume movement and to understand emissions. Additional carbon monoxide sensors were deployed near the forest floor on a transect inside the burn unit(s) near thermal paint boards to provide a relative understanding of carbon monoxide emissions and flame temperature. The BlueSky Framework produced 1.33-km predictions of smoke plume transport and surface concentrations during the potential prescription burn window. Modeled data produced by the BlueSky Framework were analyzed and compared with the observations. The objective of this research was to gather the necessary data required to modify or develop a pathway within the BlueSky Framework suitable for low-intensity/smoldering emissions often found during and after prescribed burning.