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Lateral Transport of Dissolved and Particulate TEIs at Ocean Margins. 228 Ra. K2-NW Pacific. INL. BNL. % Transmission Along Line W. Attributes of Line W as a GEOTRACES section.
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Lateral Transport of Dissolved and Particulate TEIs at Ocean Margins 228Ra K2-NW Pacific INL BNL % Transmission Along Line W
Attributes of Line W as a GEOTRACES section • Detailed hydrographic template within which to interpret geochemical profiles (proposed PO program to run until 2013). • Frequency of cruises between Woods Hole and Bermuda facilitate re-occupation of stations along transect (Process studies? GEOTRACES Intercalibration Station?). • Intersects with planned ORION/IOOS PIONEER program designed to characterize shelf-slope processes on NW Atlantic margin. • Intersects major components of MOC (DWBC and Gulf Stream). • Sharp, well-defined contrasts in water mass source/age/history. • High productivity margin. • Significant and distinct lateral particle fluxes in intermediate and bottom nepheloid layers. • Prior and on-going sediment trap studies. • Ideal for studies of elemental boundary scavenging. • Potential western limb of an east-west transatlantic GEOTRACES section that interests major particle flux time-series stations. http://www.whoi.edu/science/PO/linew/index.htm
PIONEER Array, Line W, and the Northeast Regional Coastal Ocean Observing System Current Boundary Pioneer Western Array Deep Line W
On-going and planned physical oceanographic measurements along Line W (J. Toole et al.) • Moorings: • Fixed instruments (moorings 2,4,6) • T/C sensors • Vector averaging current meters (VACMs) • Moored Profilers (MMPs, moorings 1,3,5) • - CTD • - ADCP • Optical backscatter • Transmissometry (proposed) 1 2 3 4 5 6 Hydrographic survey cruises: - CTD - Nutrients - Dissolved O2 - I-129 - CFCs/SF6 - Optical backscatter + transmissometry
Composite mean property sections (1995 and 2006) along Line W. Average, net southward DWBC transport across Line W is estimated to be 16 Sv. (Joyce et al., 2005)
Recent and proposed biogeochemical flux studies on Line W Sediment traps
The Northwest Atlantic Margin is characterized by high mass fluxes! Line W (mooring @ 3000 m isobath) Global variations in mass fluxes for particles intercepted by sediment traps deployed within or below the mesopelagic zone
Line W Mooring deployment timelines (past and proposed) Spring 2004 Spring 2005 Spring 2006 Spring 2007 Spring 2008 Spring 2009 Spring 2010 Spring 2011 Spring 2012 Spring 2013 Possible 3000 m Trap mooring WHOI funded Proposed WHOI funded NSF-CO funded NSF-CO funded Proposed Proposed Possible 2000 m Trap mooring WHOI funded Proposed Proposed 4700 m Trap mooring PO moorings Toole proposal Toole proposal Toole proposal Toole proposal Toole proposal NSF-PO funded NSF-PO funded NSF-PO funded NSF-PO funded
An E-W transatlantic GEOTRACES section? Line W ESTOC Bermuda OFP
Line W PO measurement program consists of a moored array spanning the continental slope plus annual/semi-annual (spring and fall) hydrographic survey cruises http://www.whoi.edu/science/PO/linew/index.htm
The NW Atlantic Margin: A Productive, dynamic and spatially heterogenous system Three-day composite satellite SST (left) and chlorophyll concentration (right) for 18-20 June 2001.
Turbidity sensor measurements from MMP deployed at 3000 m (Station W) Jan 30, 2005