Quantification of salt dust pathways from a groundwater-fed lake:Implications for solute budgets and dust emission rates

[1] Emissions of salt dust from the shores of saline lakes significantly impact lake chemistry, air quality, transportation, human health, and climate. Quantitative methods for assessing these emissions, however, are still in the developmental stage. We investigate salt pathways from groundwater to dust using an approach that takes advantage of opportune conditions at a groundwater-fed, saline lake in the Nebraska Sand Hills region. The mass of salt in the lakeshore surface crust and soil was measured, as well as in the dust on the surrounding dune field. These data, together with information on the lake hydrology, show that dust emission is an important mechanism controlling lake salinity, even though a mere fraction of the salt crust is deflated each year under extant climatic conditions. Wind data collected at the lake site indicate high wind speeds capable of dust mobilization. Therefore, the physical and chemical bonding of salts in the crust is offered as the primary limiting factor for dust emission rates.