Submitted to: American Association for Aerosol Research
Publication Type: Abstract Only
Publication Acceptance Date: April 4, 2003
Publication Date: April 4, 2003
Citation: Sharratt, B.S. 2003. Progress Toward a Dust Emissions Model for the Columbia Plateau. American Association for Aerosol Research. Technical Abstract: The Columbia Plateau is a region susceptible to wind erosion due to the preponderance of strong winds that typically occur in spring and autumn when soils are dry. These conditions have resulted in severe dust storms that not only have impaired driving of automobiles and caused accidents, but that may also have adversely affected human health. A model for predicting fugitive dust emissions from agricultural soils in the Columbia Plateau was introduced in 1996. Dust emissions are predicted based upon the amount of eroded soil, a dustiness index, and wind speed. The amount of soil eroded by wind is a function of surface wind energy, soil surface characteristics (i.e. quantity of surface crop residue, soil surface roughness) and soil physical properties (i.e. soil crusting, soil erodibility, soil moisture). The dustiness index is the fraction of fine particulates (smaller than 10 microns) in the eroded soil and is assumed to be equivalent to the fraction of fine particulates within the upper soil profile. Progress has been gradual in defining all parameters in the model. Field studies were undertaken to define the relationship between soil loss and wind energy, surface residue cover, surface roughness, and soil erodibility. In addition, the dustiness index has been defined for a range of soil types common to the Columbia Plateau. Parameters have not been defined for the relationship between soil loss and soil moisture and soil surface crusting. For non-crusted and dry soils, the model has performed reasonably well in simulating field dust emissions. Further efforts are needed in parameter specification to predict dust emissions from agricultural soils that are temporally moist and subject to crust formation.