What is the source of dust to West Antarctica?

Alejandra Borunda, Columbia University of New York, Palisades, NY, United States, Gisela Winckler, Columbia U. / LDEO, Palisades, NY, United States, Steven L Goldstein, Columbia University, Palisades, NY, United States, Michael R Kaplan, Lamont-Doherty Earth Observatory, Palisades, NY, United States and Paul Travis Vallelonga, Centre for Ice and Climate, Copenhagen, Denmark