Barrow’s Arctic Ocean Developing a Cabled Seafloor Observatory to Complement the Barrow Global Climate Change Facility the “BGCCRF” Developing a Cabled Seafloor Observatory to Complement the Barrow Global Climate Change Facility the “BGCCRF”

BGCCRF Design Process Developed through a series of meetings with user groups Original Design included Seawater Intake Developed through a series of meetings with user groups Original Design included Seawater Intake

Seawater Intake Meeting Held at MBARI October 10, 2003 Approximately 30 attendees Discussed multiple uses Constraints on seawater intake Use as a “cable run” for Seafloor Observatories How to install it? Held at MBARI October 10, 2003 Approximately 30 attendees Discussed multiple uses Constraints on seawater intake Use as a “cable run” for Seafloor Observatories How to install it?

Everyone was excited about the potential for Seafloor Observatories……..  Broadband Acoustic Monitoring - marine mammals, acoustic tomography, volcanic activity  Visual Monitoring - scheduled, triggered or remotely triggered  Seafloor Seismometers  Oceanographic - monitor water column  Active Acoustic - observe currents and ice  Tethered -reeled in and out  Autonomous Underwater Vehicle Docking  Intercommunication between nodes  Broadband Acoustic Monitoring - marine mammals, acoustic tomography, volcanic activity  Visual Monitoring - scheduled, triggered or remotely triggered  Seafloor Seismometers  Oceanographic - monitor water column  Active Acoustic - observe currents and ice  Tethered -reeled in and out  Autonomous Underwater Vehicle Docking  Intercommunication between nodes

….and nervous about the cost  Slant drilling for 4-5 km is near the limit for the technology  Not Cheap  The Seawater intake has been eliminated from the design.  Slant drilling for 4-5 km is near the limit for the technology  Not Cheap  The Seawater intake has been eliminated from the design.

Spin Cycle “On”  Elimination of the Seawater Intake is an Opportunity  Permits us to select optimum Site for Installation  Where is it?  Elimination of the Seawater Intake is an Opportunity  Permits us to select optimum Site for Installation  Where is it?

Land-Based Sea Ice Radar at Barrow, AK data courtesy of Andy Mahoney-UAF  10 kW X-Band marine radar  level ice, open water and radar shadows appear black  detects ice floes up to 10 km from shore  captures detailed development of landfast sea ice

Edge of landfast ice; courtesy Andy Mahoney-UAF

High-Resolution Bathymetry off Barrow

Data Needs to identify best Cable Location Multi-beam Bathymetric Survey identify bottom features to avoid or exploit Sidescan Survey map ice gouges Chirp sub-bottom profiler Survey estimate penetration depth of ice keels Repeat identify the active areas