Southern Ocean GLOBEC pre-cruise meeting

9 January 2001

Process cruise April/May – ca 10 h light

 

PI Task Time Repeated

Costa/Burns Crabeater seals 2-6 h 7x per cruise

Fraser Penguins 6 h 15x per cruise

Ice stations/opportunistic, no open water stops

Fritsen CTD in open water 1 h 1/d

CTD in ice 1 h 1/d

Ice station 3-4 h 1/d

Requested 10L bottles for CTD

Sample forming grease ice/frazil ice w/ buckets

Vernet?

Zhou ADCP survey 20 km box 24 h 2x per station

1m MOCNESS 4 h 2x/d

Daly HTI acoustic tow w/ ADCP (tow speed too slow?)

HTI towed w/ net tows as possible

HTI drift 0.5 h 1/d

HTI on station as possible

Live net tows 1 h 2/d

Torres 10 m MOCNESS 3 h 1/d (5/sta)

Dive 4 h 1/d

Meat tow 1 h 1/d

UW/nutrients CTD

Perovich ARGOS drifter on floe (Sta 5?)

+ CTD survey 3-6 h 1x/cruise

Data loggers

Total time open water, 5 d per station

2 ea ADCP 48 h

5 ea CTD 5 h

5x-2 ea/d MOC 1 20 h

5x – 1 ea/d MOC 10 15 h

5 x live nets (2) 10 h

5 x meat tows 5 h

2 x diving 8 h

Total 111 h = 4.5 d

Total time ice station, 5 d per station

Day operations:

Seals 6 h

Penguins 6 h

Dives 6 h

Ice 6 h

CTD/optics noon

Night operations:

ADCP 1 d - 24 h survey- predator survey, get predator info from Polarstern

MOC-1 8h

MOC-10 3h

Live nets 3h

HTI drift 1h

15 h other work

6 h for "day" work

21 h

15 d ice sta (3 x 5) [Jose you had 18 d on the board instead of 15 d, not sure why now…]

10 d open water (2 x 5)

25 d on sta

+ 3 – 4 d transit

= 28 science days, 4 d for weather + additional work

 

Station location/procedures

(1) Obtain predator/prey information from Polarstern and penguin satellite positions for general area,

  1. ADCP survey 20 km grid, locate predators/prey aggregations,
  2. Stop 6-7 h centered around midday daylight for diving, ice sta, penguins and mammals
  3. Net tow etc during other hours, moving to new location inside grid.

 

Process station site criteria We should continue to discuss these locations

Sta 1 – Objective to sample shelf, shelf break, and off shelf communities (ACC)

1000 m isobath (ca 200 km offshore ?)

The August process group objected to a station so far off-shore and argued for the station to be located nearer shore where they would be more likely to find ice in Aug. We agreed to have a Sta. 1a and 1b. Sta 1b will be directly shoreward of Sta 1a. Fritsen will collect water samples for microbial biology at both locations (6 h stop).

The August process group would like to investigate different ice types and to relocate same ice where drifter was deployed in April/May in order to examine the temporal evolution of ice conditions. L. Quetin would like 3 ice stations, 75-100 km apart, reoccupying 2 sites in 7/10 – 10/10 rafted pack ice.

Sta 2 – Objective to sample canyon effects on hydrography, prey and predators. Approximately in axis of canyon.

Sta 3 – Objective to sample perennial pack ice, highest probability of finding early forming sea ice. (R. Smith - Buoys deployed in June at ca. Sta 3 didn’t move beyond 6 km for 1.5 m; C. Fritsen didn’t think that ice maps indicated perennial ice at this location.)

Sta 4 – Objective to sample fast ice and deep into Marguerite Bay?

Sta 5 –Objective to sample large predator aggregations. The site of this station was especially questioned. D. Costa said that Sta. 5 was located to be in the vicinity of Deone Is (sp?) which had seals and penguins. Aggregations of seals and penguins during winter were sited approximately at the intersection of Sta. 2 and 5 boxes.