BEAUFORTSHELF

Alaska: Beaufort Shelf Ocean Current Mapping Program Using Shore-Based High Frequency Radars

15 July 2009 - 15 November 2009

Lead Scientist: Thomas Weingartner

Observatory: OSC

The PIs maintained a cross-shelf array of oceanographic moorings off the coast of Alaska for a one-year period extending from the near-shore (within the landfast ice zone) to the shelfbreak. This was accompanied by seasonal high-resolution hydrographic measurements and mapping of surface ocean currents using shore-based high frequency radars. They analyzed sea ice displacement and deformation using satellite data and used autonomous acoustic recorders to detect calling marine mammals. By interpreting the results in the context of the previously obtained data, by using the seasonally-varying ice cover as a proxy for interannual changes in the ice, and by collecting first-ever baseline measurements, the PIs were able to assess many important aspects of how the ABS responds to an ice-diminished Arctic. This joint physical/biological program assisted in determining how the Alaskan Beaufort Sea (ABS) atmosphere/ice/ocean/marine-mammal system works and the consequences of a warming climate. The focus was on the related problems of how the wind-forced response due to storms and the cross-shelf exchange, including that due to rivers, change under variable and changing ice conditions, and to understand the seasonal variations in marine mammal utilization of the ABS.