Dr. Mary-Louise Timmermans
August 3, 2011
The mooring team and Deck Department deployed Beaufort Gyre Observing System Mooring B in the fog and 9/10th ice cover today. Just prior to the start of deployment operations, all the mooring components were hoisted on deck from the ship's forward hold using the crane. Instruments are stored here to prevent freezing, and the hold provides a large comfortable working space for preparations.
The deployment went smoothly, following the same anchor-first procedure as for the deployment of Mooring A (see Dispatch 10), until a nick was noticed in the plastic jacket protecting the cable of the mooring line. The nick in the jacket exposed the metal wire leaving a site for corrosion and deterioration of the line.
During any deployment, several members of the team working at the Lebus winch system are constantly watching for any defects in the line being paid out or for problems in the wire wraps or tension. Jeff Pietro (WHOI) used vulcanizing tape for a quick repair of the compromised wire and the deployment proceeded.
The scientific interest of the Mooring B site is that it provides information on water-column and sea-ice properties at the northwest boundary of the Beaufort Gyre - for example, how the relatively fresh water (that originates from sea-ice melt and river run-off) and ocean heat content are changing from year to year. In addition, at this site we've seen more eddy activity than at other BGOS mooring sites. Energetic ocean eddies, observed at all depths in the water column at site B, can transport ocean heat large distances across the basin. A component of our ongoing research relates to investigating the origin and movement of these eddies.