First posted February 27, 2011 Version 2 November 20, 2014 ADCP bottom track direction corrected -------------------------------------------------------------------------------- BEST Bering Shelf Project (Bering Ecosystem Study) University of Washington 2009-2010 Bottom Moored Oceanographic Data NSF Grant ARC-0732428 The Bering Ecosystem Study seeks to understand how the enormous Bering shelf, containing one of the most productive marine ecosystems in the world, has changed significantly in recent decades, both physically and biologically, and whether in concert with regional climate fluctuations. Furthermore, the Bering shelf offers a physical and ecological continuum between the North Pacific and Arctic oceans, with the flow field transmitting changes to other ecosystems to the north. Part of this effort is BEST Bering Shelf Project, a two-year field effort collaborative between the University of Alaska Fairbanks (UAF) and the University of Washington (UW). During this project we address the impact of physical variability on the processes and structure of the Bering shelf ecosystem, with special emphasis on how freshwater redistributed by the shelf circulation or introduced from sea ice modifies stratification and nutrient distributions. In particular, we seek to understand how changes in sea ice affect advection and mixing; how variable fluxes of low-salinity, nutrient-deficient (but iron-rich) coastal waters affect production; how cross-shelf fluxes are established and altered; how these fluxes might respond to climate change; how the seasonal stratification cycle is controlled; and how the buoyant coastal flow evolves. We use moored instruments and shipboard hydrography (including extensive O-18 sampling) to address this problem set. During 2008-2010, nine ocean moorings have been deployed on the eastern shelf of the Bering Sea. Vertically distributed instruments measure ocean properties at fixed depths, recording internally. These are located along three lines (N = North, C = Central, S = South) perpendicular to the isobaths, roughly centered on Nunivak Island, at approximate depths 55m, 40m, and 25m. (PDF map provided.) The first set of UAF-UW BEST moorings, nine in all, was deployed in July 2008 from the USCGC Healy. These were recovered and replaced in July 2009 from the RV Point Sur, which also recovered them in July 2010. The locations of the moorings are shown in Figure 1 as red squares, circles, and stars; the red triangles denote NOAA moorings. Depending on depth, the moorings carry various instrumentation. For example, at the outermost locations on each line (square, circle, and star), over the 55 m isobath, each mooring has an ice-avoiding modem-linked temperature and conductivity recorder at 10 m, another temperature and conductivity recorder with a fluorometer and turbidity sensor at 22 m, below that a chain of 15 precision temperature recorders, then an acoustic Doppler current profiler at 46 m, and finally another temperature and conductivity recorder 2 m above the 55 m bottom. This archive contains the data from the UW instruments on the deepest moorings of the C-line and S-line deployed in 2009, labeled C55-09 and S55-09. Data from 2008-09 and from the UAF instruments are posted in separate archives. BEST 2009-2010 Bottom-Anchored Moorings- Mooring S55-09 Latitude 58 degrees 35.414 minutes North Longitude 168 degrees 23.543 minutes West Sounded ocean depth = 55.6 meters Time at depth = 2009/191/0551 UTC Time of release = 2010/204/1635 UTC Mooring C55-09 Latitude 60 degrees 10.410 minutes North Longitude 170 degrees 05.108 minutes West Sounded ocean depth = 56.0 meters Time at depth = 2009/193/0636 UTC Time of release = 2010/209/0222 UTC General information about BEST (Bering Ecosystem Study) can be found at http://bsierp.nprb.org/index.html and BEST data are permanently archived at http://www.eol.ucar.edu/projects/best/ In reports and publications that use these data, please acknowledge their source: K. Aagaard, BEST Bering Shelf NSF Grant ARC-0732428. For further information, please contact Dr. Knut Aagaard aagaard@apl.washington.edu (206) 543-8942 Roger Andersen roger@apl.washington.edu (206) 543-1258 at Polar Science Center, Applied Physics Lab, University of Washington 1013 NE 40th, Seattle, WA 98105-6698 USA FAX (206) 616-3142