During the 20th century, the city of Los Angeles diverted surface water flowing into Owens Lake for water supply, transforming the large, closed-basin, saline lake into a small brine pool surrounded by dry playa. Under high winds, the exposed lakebed produced large amounts of airborne dust, resulting in the highest concentrations of airborne particulate matter with an aerodynamic diameter of 10 micrometers or less (PM10) in the United States. Since...