Date: Sun, 19 Jan 2003 07:44:08 +0000
To: lterpalpi@icess.ucsb.edu
From: Robin Ross <Robin.Ross@lmg.usap.gov>
Subject: second high density grid
Cc: fraserbi@palmer.usap.nsf.gov, ducklohu@lmg.usap.gov,
   iannuzzi@ldeo.columbia.edu, kozlowwe@lmg.usap.gov, geiszhe@lmg.usap.gov

Hello,

The weather treated us right and we managed to get both high density 
grids done before leaving for the outer stations of the 400.* line. 
At 2205 (GMT) on 19 Jan we have 2200 m of wireout at 400.180.

The grid plan for the second high density grid has a different 'look' 
than that for the baseline HD1 with its 2.5 km resolution and 
rectangular layout.  We based the transect plan on the chart with 
dots for penguin locations that Bill and Donna sent to us the 
afternoon of 17 Jan.  Two transmittors had been on a series of birds 
for several weeks, and 4 others had been on penguins for a few days. 
In this case I think 'few' means 4 d, but I am not  totally clear 
about that.

Heidi, Brett and I went up to the bridge and looked at the 
distribution of the 'locations', and it looked to us like the vast 
majority of the locations were in Wylie Bay,  and between the shore 
and the 10 km picket line.  The furthest south one was at 64° 51.6'S, 
and our PL10.175 is 64° 51.65'S.  Also most locations were between 
two lines, one drawn from Dream I past the Joubins, and one from 
Gamage Point to Outcasts.  The Captain looked at the charts with us, 
to help figure out what was easy navigation or something we had done 
before so that we could do the 4.5+ kt survey speed.  Lots of shallow 
rocky areas in that region.

Ultimately we decided do the survey as 'half circle' transect lines 
with Torgersen I as the center.  We started just to the east of the 
Joubins with simultaneous bird and acoustics, moved in to the 10 km 
picket line start point in Wylie Bay and did a CTD cast near Dream 
Island.  Then we did the simultaneous bird and acoustics along the 10 
km picket line out to the 205 degree point, moved in to a 7 km (from 
Torgersen) picket parallel to the 10 km, heading back to Wylie Bay 
and Halfway Island.  Then to the inner most point on the 3.7 km 
picket where we did a CTD cast (close to Station J).  We did the 
entire 3.7 km picket, moved out to the 10 km picket on the Biscoe Bay 
side and did the 10 km picket back to the 205 degree point where we 
finished with a CTD cast.  There were several XCTDs along the way, 
but we will run out so we were conservative.

None of that probably made any sense unless you have a map of the 3.7 
and 10 km picket lines in hand! We started at 0900 and ended about 
2000, trying to have good daytime for the bird obs.

Prior to the high density grids we did 3 net tows in the Wylie Bay 
region - two tows were sparse, but the third, a target tow, netted us 
3 halibut tubs full of krill with a few salps sprinkled here and 
there.

We are back on schedule to visit Rothera on 25 january - the HMS 
Endeavour paid her visit earlier than expected so there is no longer 
a conflict.  We are also a day behind due to the storm, so we hope 
not to lose any more time.

cheers,
Robin 

