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Woods Hole Oceanographic Institution

Sarah B. Das

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Publications
»Antarctic meltwater flux, GRL, 2013
»Tropical Pacific influence on W. Antarctic marine aerosols, J. Climate, 2013
»Thwaites Glacier, Antarctica accumulation, GRL, 2013
»ACCMIP multi-model global nitrogen and sulfur deposition dataset, ACP, 2013
»Influence of ice sheet geometry and supraglacial lakes on seasonal ice flow, TC, 2013
»Greenland Iron Export, Nature Geosc, 2013
»Greenland Organic Carbon Export, GCA, 2013
»Amundsen Coast Sea Ice and Polynya Variability, JGR, 2013
»Ice Core 10Be Records, EPSL, 2012
»Antarctic Ice Sheet Surface Melting, JGR, 2012
»Greenland discharge isotope mixing model, J. Glac., 2011
»Future Science Opportunities in Antarctica and the Southern Ocean, NRC Report, 2011
»Greenland Ice Sheet DOM, GCA, 2010
»Ice Sheet Hydrofracture and Water-transport Model, GRL, 2009
»Greenland Supraglacial Lake Drainage, Science, 2008
»Greenland Seasonal Speedup, Science, 2008
»West Antarctica Holocene Climate, JGR, 2008
»Greenland Accumulation, J. Climate, 2006
»Melt Layer Formation, J. Glac, 2005
»Whillans Ice Stream Deceleration, GRL, 2005
»Siple Dome Temperature Variability, Annals Glac., 2002
»Patagonian Icefield SAR, JGR, 1996


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A. S. Criscitiello, S. B. Das, K. B. Karnauskas, M. J. Evans, K. E. Frey, I. Joughin, E. J. Steig, J. R. McConnell, B. Medley, Tropical Pacific influence on source and transport of marine aerosols to West Antarctica, accepted, J. Climate, 2013

The climate of West Antarctica is strongly influenced by remote forcing from the tropical Pacific.  For example, recent surface warming over West Antarctica reflects atmospheric circulation changes over the Amundsen Sea, driven by an atmospheric Rossby wave response to tropical sea surface temperature (SST) anomalies.  Here, we demonstrate that tropical Pacific SST anomalies also influence the source and transport of marine-derived aerosols to the West Antarctic Ice Sheet.  Using records from four firn cores collected along the Amundsen Coast of West Antarctica, we investigate the relationship between sea-ice modulated chemical species and large-scale atmospheric variability in the tropical Pacific from 1979–2010.  We find significant correlation of marine biogenic aerosols and sea salts with SST and sea level pressure in the tropical Pacific.  In particular, La Niña-like conditions generate an atmospheric Rossby wave response that influences atmospheric circulation over Pine Island Bay.  Seasonal regression of atmospheric fields on MSA reveal a reduction in onshore wind velocities in summer at Pine Island Bay, consistent with enhanced katabatic flow, polynya opening, and coastal dimethyl sulfide production.  Seasonal regression of atmospheric fields on Cl- reveal an intensification in onshore wind velocities in winter, consistent with sea salt transport from offshore source regions.  We find both source and transport of marine aerosols to West Antarctica are modulated by similar atmospheric dynamics in response to remote forcing.  Finally, our regional ice-core array suggests there is both a temporally and spatially varying response to remote tropical forcing.

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