8:00 a.m.:  Another clear day for the Revelle which is continuing the fine scale survey.  Later today the remaining drifters will be deployed and some station work will take place.  Amanda Briggs works on preparing the bio-optical profiler package.

11:00 a.m.:  Station work begins.  The first task was the release of the three remaining drifters.  The drifter assembly consists of a large beach ball-sized sphere that contains the optical sensors, GPS receiver, and ARGOS transmitter.  The sphere is attached by a long cable to a long tube made of a black mesh fabric material that hangs several meters down below the surface.  The purpose of the mesh fabric tube is to cause the drifter to move with the water currents several meters down rather than being blown by the wind across the surface.  Shown below launching the drifter are Amanda Ashe, Renato Castelao, and Guido Corno.

After the drifters were released, the TSRB was deployed for 25 minutes.  Guido Corno is shown monitoring the tether.

The next item to go over the side was the bio-optical profiler package.  As before, it is lowered on a cable and stays in the water for close to two hours.  It is lowered slowly and every few meters it is halted so detailed readings can be made.  Amanda Briggs and Chris Wingard are shown below.

Chief Scientist Report for 12 August 2002

Here's an update for Monday morning, 12 August. Unfortunately, we have
some bad news to report. At about 0900 PDT the SeaSoar vehicle crashed
into the bottom on the shallow end of line 7 off Bandon. Upon recovery,
the Optical Plankton Counter (OPC) had been sheared off the bottom and the
nose of SeaSoar was dented. There were rocks, mud and a piece of benthic
sponge in the nose opening of Seaoar. The temperature and conductivity
sensors mounted in the nose of SeaSoar were jarred, but may be okay as
further tests will tell. Otherwise, the vehicle and instruments are okay.
We have a second OPC and backup temperature and conductivity sensors on
board. We also have a spare SeaSoar nose. We are now working to replace
all the damaged parts and hope to have SeaSoar back in operation tomorrow
(Tuesday) afternoon. The bottom collision was caused by an incorrect
setting on the ship's echosounder, minimum depth was set too deep as we
came into shallow water. We will renew our vigilance in making sure the
depth information going into the SeaSoar flight controller is set
correctly.

While the SeaSoar is under repair, we deployed 3 bio-optical drifters in
the upwelling jet along line 7 off Bandon. We are just now finishing up
the TSRB, bio-optics and CTD/rosette profiling near the drifters. We then
will survey line 7 with the HTI deployed and the bird and mammal observers
on the O3 deck. At night we will do a CTD section along the FM line. At
first light we will deploy the HTI and resume our survey along lines 7a and
8. These should be completed by Tuesday late afternoon and we will make a
decision about whether the SeaSoar is ready to go. We will then continue
surveying on the Fine-Scale south grid.

The weather is holding and it's another clear day off the Oregon coast.
New Horizon is working near us. We're looking forward to a productive
final week.

---Jack Barth, Chief Scientist R/V Roger Revelle
filed 1400 PDT August 12 2002

3:00 p.m.:  The CTD/rosette was recovered as the last item at this station.  Whenever an instrument on a cable is deployed or recovered over the side of the ship, "tag lines" are used to control the swinging motion of the instrument.  Tag lines are ropes that are held tight by two crew people under the direction of the resident technician and are vital under rough conditions to prevent damage to the instrument or injuries to the crew.  Shown below Chris Wingard and Mauricio Andrades use tag lines during a CTD/rosette recovery under the direction of resident technician Tami Baiz.  Assisting is Cidney Howard.

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