Mineral dust abundance and sources in the global free troposphere
Karl D Froyd1, Pengfei Yu2, Daniel M Murphy3, Gregory P Schill4, Agnieszka Kupc5, Christina Williamson6 and Charles A Brock4, (1)NOAA Boulder, Boulder, CO, United States, (2)University of Colorado at Boulder, Boulder, CO, United States, (3)NOAA, Chemical Sciences Laboratory, Boulder, United States, (4)NOAA Chemical Sciences Laboratory, Boulder, United States, (5)University of Vienna, Faculty of Physics, Vienna, Austria, (6)Finnish Meteorological Institute, Climate Research Programme, Helsinki, Finland