Dear Family, Friends, and Colleagues,

Not everything on a research cruise goes as planned or hoped. We headed south last Saturday on a dual-purpose mission. The NOAA research ship Ronald Brown had reached the ice edge in 2007 doing the “P18” cruise for our long-term program, and we hoped to extend their work south to the Antarctic continental shelf break somewhere near 100°W. There was also the issue of mooring recoveries in that same general area for LDEO investigator Stan Jacobs. We knew from satellite images sent to the ship that sea ice covered nearly 100% of the surface in the area, but the Palmer can handle sea ice if not too thick. Still, we decided to first see how long it took us to get to our desired end point, allotting a certain maximum amount of time to icebreaking (in accord with our master plan for the remainder of the cruise), at which point we would know how much time we had for our work plus the icebreaking and steaming as we headed back north. Admittedly success with the mooring recoveries seemed remote because those could not be done in full ice cover, but one never knows until trying.

We reached the ice edge at the expected point along the track and progressed well at first. Then the going got tough, not so much because of ice thickness as because of the large amount of snow on the ice. Snow rubs against the ship’s hull much like sand would, sapping power and momentum as the ship presses forward. Only about 20 miles into the ice (20 miles straight line, but many more miles as we worked around large snow-covered floes) the Captain and Ice Pilot decided enough was enough. In the morning nothing looked any better, so we took advantage of being in a large floe to have an ice party - free time for those on board to be on the ice a bit. Everybody had a good time - playing soccer, walking around, playing in the snow. After everybody was back aboard we pulled into an opening in the ice and did a CTD cast. That cast showed nothing remarkable compared to nearby data from 2007. There we were, nearly 50 miles from our targets - either the shelf break or Jacobs’ moorings - but we could not go further. There being no point to lingering, we headed back north to the main 67°S line.

Thus we were not able to extend the P18 line south through the ice to the Continent and we were not able to recover any of Stan Jacobs’ ice-covered moorings. The only benefit of the way this worked out was that we spent at least one day less on the excursion than planned so now have about a day’s worth of weather time in the schedule between now and the end of science activities five and a half days from now. This should enable us to reach the eastern end of the west-to-east section which is one of our main focus areas.

We always enjoy our trips through the ice. We did not see many penguins this time (though there were a few, including Emperor penguins) but there were many seals hauled out onto the thicker floes. The leads (openings in the ice) are freezing over and there are many 4 to 10-foot holes punched up through the thin ice. The culprits? Orcas (Killer Whales) on the lookout for seals on the thicker ice nearby. I saw a pair of them stick their heads out of one of the holes to take a look-see.

The weather has been unusually good. That may well change, but we are back on “the line” and for now we are mowing down the final stations one by one, making very good progress. Everyone has their sights set on keeping steady and focused: Get the job done. Then go to port!

All is well on the Nathaniel B. Palmer.

Jim Swift
Chief Scientist
NBP-1102 / S04P