8:00 a.m.:  Sunny skies greet the Revelle on this Sunday morning.  During the early morning hours the ship has performed CTD/rosette casts at five different stations in close proximity to each other.  These stations are in-between the north fine scale survey and the south fine scale survey.  When the station work is complete, the next task will be to locate the bio-optical drifters that were deployed several days ago.  When they are located, additional station work (CTD/rosette, bio-optical profiling, and TSRB) will be done at that location before moving on to the south fine scale survey later this evening.

One noteworthy observation can be made about the water color.  Near shore over the continental shelf the color of the water is an obvious brown and brown-green color due to the high productivity of the plankton. The factors that influence the productivity of the plankton include the wind driven upwelling of cold nutrient-rich water which is one of the phenomenon being studied on this cruise.   Farther offshore in deep waters the water is a crystal blue color indicating an absence of high concentrations of plankton.  

Update  8:15 a.m.:  The bridge reports the drifters have been spotted.  Station work will continue in this area as planned.

10:30 a.m.:  With the drifters located earlier than expected, plans have changed.  Station work has commenced with a CTD/rosette cast, TSRB deployment, and the bio-optical profiler package.  Once the station work is done here, plans call for a rendezvous with the New Horizon and the fishing vessel Frosti for additional station work and SeaSOAR towing.   Shown below is 3rd mate for the Revelle, Matt Michalski,  in control of the ship aided by Renato Castelao who kept an eye on the drifters.

Three more drifters will be deployed on Monday. Twenty-four hours before they are released, they are turned on, labeled with return addresses, and checked to make sure the transmitters are working properly. Shown here is Renato preparing the remaining drifters.  The graphic shows the paths taken by the three drifters released on the first day of the cruise as well as the paths for the three drifters released August 8.

12:00 p.m.:  Station work is almost complete.  Amanda Briggs monitors the bio-optics profiler data while the instruments are still in the water.  Chad Waluk and Chris Wingard work on repairing the SeaSOAR connectors that were damaged on Saturday.  As plans change, the chief scientist posts updates on the white board in the hall outside the labs.  Because the science crew is on rotating shifts and meetings would be difficult to have to announce changes in the activities, the white board has become the place to check for the latest information.

Chief Scientist Daily report for 10-11 August 2002

After completing the North Fine-Scale survey at 11pm on Sat (8/10) night,
we transited north to 44 15.0'N. This is just offshore of the PISCO
Strawberry Hill measurement site. We conducted 5 CTD stations from 45 to
100 m depth during the night from 2-6 AM. We were especially interested
in measuring dissolved oxygen through the water column given the
previously reported findings of low oxygen waters in this area. We found
freshly upwelled, quite salty water (33.914 psu) near the bottom, but
preliminary results showed that it was not low oxygen water. Each CTD
station included samples for nutrients and various phytoplankton
properties (chlorophyll content, pigment composition). Great job by the
CTD team (Steve Pierce, Rachael Sanders, Guido Corno and SIO ResTech Tammy
Baiz, and also assisted by Amanda Ashe)!

As we pulled onto our final station in 100 m of water, one of the bright
orange bio-optical drifters was only 50 m off the bow of the Revelle! I
had made an educated guess the night before about where the drifters would
go, but it was pure luck that they were that close to our CTD station.
The other two drifters were close by, within about several hundred meters
of each other. So we launched into our station work near the drifters
including a TSRB session, and 1.5 hours of bio-optical profiling.

Meanwhile, Chris Wingard, Marc Willis and Chad Waluk worked hard to repair
the SeaSoar from the two minor problems we had toward the end of the North
Fine-Scale sampling. Chris made a new cable for the PAR sensor and, with
assistance from Chad, made a new cable for the CTD to the ac-9 we're
flying on top of SeaSoar. The light absorption channel had gone out on
ac-9 #152 (Barth's ac-9) before the last line of the North survey. So we
swapped in ac-9 #141 from the Cowles group. Marc and Chad reattached all
the instruments to SeaSoar and buttoned it up in record time. Another
great "pit stop" by the OSU SeaSoar crew!

We had to reassemble the SeaSoar quickly because of the opportunity to
work with both the R/V New Horizon and the R/V Frosti along the 44 0'N
(Heceta Head) line this afternoon. We all agreed that taking a closer
look at the region near 124 42'W on the inshore side of Heceta Bank where
the top trophic group saw lots of humpbacks and sea birds was worth doing.
The observers reported sightings of about 50 humpbacks along this line the
previous day. So we all agreed to meet at this point and to work together
until around midnight tonight (Sunday).

On the inshore part of this line the water is the color of root beer, a
deep brown from high phytoplankton concentrations. It appears that the
whales and birds are on the outside, western edge of this high chlorophyll
feature. We should have the data in hand, from physics (temperature,
salinity, circulation, water clarity), chemistry (nutrients) and biology
(phytoplankton, zooplankton, birds and mammals) to sort out the spatial
structure of this community.

Next up is towing the SeaSoar and HTI to Line 7 off Bandon, deploying
another set of bio-optical drifters, and then conducting a 2-2.5 day
survey of the southern region around Cape Blanco.

Dinner tonight on the Revelle consisted of rib-eye steaks cooked on the
fantail barbeque, butterflied prawns, roasted potatoes, vegetables and
birthday cake for Amanda Ashe. Excellent!

---Jack Barth, Chief Scientist R/V Roger Revelle
filed 1900 PDT August 11 2002

9:00 p.m.:  The Revelle makes a close rendezvous with the New Horizon and the Frosti.  Using the data from the HTI instrument that uses sound to image particles in the water, Kasey Legaard looks for well defined layers of biomass.  The depths of these layers are sent by radio to the New Horizon and the Frosti which will then use sampling nets and target those depths.  A clear but cool night afforded excellent views of the Moon and Venus.

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