Friday, July 13th, what are we doing out here?!

We left Newport, Oregon at about 4:14pm, crossing the bar into somewhat heavy seas.  Winds were up and the 165 foot R/V New Horizon can roll a bit in the swells.

During our cruise out to the first recovery site, we explored the ship.  The main hubs of activity for the scientific crew, that's us, are the main lab, the fantail (back deck, close to the water), and the mess.  These are all on the same level ('main deck') on the New Horizon.  Our cabins were 'cozy,' with Erik and I sharing with others on the '01 deck' (1 up relative to the main deck), and Erika assigned her own cabin below the main deck.  The differences are the ride (rolls more in the 01) and the noise (more engine noise in the below deck). 

We made our first recovery site at about 9:30 at night, just after darkness fell.  This was a challenging recovery.  Ray and Matt, from Scripps Oceanographic Institute (SIO) and Oregon State University/NOAA (OSU) communicated with the ocean bottom seismometer (OBS) using an acoustic transponder attached to the ship's hull.  They controlled this using a 'deck box.'  The first command issues was an 'enable,' to wake up the instrument.  After it responded affirmatively, they then checked with the bridge, and received permission to send the 'drop anchor' command.  The OBS are weighted with ejectable anchors, such that they fall to the ocean floor during deployment, then rise up for recovery later on (9 months in this case).  After the OBS acknowledges receiving the drop anchor command, 'burn wires' within the unit (a SIO 'abalone') it takes several minutes for the wire to burn through and the anchor to release.  Once this is done, the OBS begins to rise through the water.  Depending on its original depth, it can take up to several tens of minutes for the unit to reach the surface.

This particular night the seas were high, and so siting the surfaced unit was difficult.  The engineers who designed the abalone, Martin, Ray, and Paul, have planned for night recover by installing a strobe light that starts up once the OBS surfaces.  There is also a radio direction finder (RFD) that the bridge crew can use to get a bearing towards the unit.  Thus, they were able to spot the unit and shine a flood light on it.  It took two tries, with the ship carefully approaching the unit so that it would move past down the starboard side.  There, the able crew of Matt, Bill, Martin and marine tech Josh (check) were able to snag it with clip hooks tied to ropes and clipped onto extensible poles (gaffs).  Once one line was secured to the OBS and the ship, the line to a winch, tied to another clip hook, was attached, and the winch was used to recover the instrument to the fantail.  Other lines are attached during this process to stabilize the unit, and ship roll and sea swells can make this a challenging operation.

After an OBS is on board, the technical crew remove the logger unit from it.  This is contained in a plastic tube that is sealed to keep sea water out, and engineered to withstand the great pressures at depth.  The logger tube is brought into the main lab, where the unit is depressurized, connected to a computer, and data are downloaded.  The logger's internal clock is also checked against GPS-time for drift.

This entire process lasted until about 11:30 pm.  Afterwards, we retired to our bunks to catch some (fitful) sleep as the ship cruised through swells toward the next recover site, with an ETA of 7:30 am.