QUANTIFYING POTENTIAL FUGITIVE DUST EMISSIONS FROM OPEN AREA SOURCES IN THE SOUTHWESTERN UNITED STATES USING THE PORTABLE IN-SITU WIND EROSION LAB (PI-SWERL)

Fugitive dust emissions from agricultural fields and natural open areas in dry, windy climates throughout the world can contribute significantly to high airborne concentrations of fine particulate matter (PM₁₀). This presentation will discuss a methodology to measure potential PM₁₀ emissions and underlying sand motion based on the Portable In-Situ Wind Erosion Lab, or PI-SWERL. This instrument, developed by the Desert Research Institute, Reno Nevada, provides a highly portable and efficient method to measure surface erosion potential in the field. Site-specific calibration methods of the PM₁₀ and sand motion sensors of the PI-SWERL will be described. The shear stress imparted on the surface by a rotating ring in the PI-SWERL unit may be scaled up to ambient wind speeds. The relationships between wind speed and PM₁₀ emission potential allow for modeling at a landscape level. An example of such an analysis, conducted on a desert dune field in the southwestern United States, will be described. The PI-SWERL is also suitable to evaluate the efficacy of chemical surface applications in reducing PM₁₀ emission potentials from erosive surfaces. Results from a field study conducted on a desert playa in the arid southwestern United States will be presented.