October 25 , 2004
Dr. Gerd Krahmann aboard the R/V Nathaniel B. Palmer...
65 S 47.6
142 E 34.1
95% ice cover, 0.5m thick
air temperature: -12C
sea surface temperature: -1.85C
10kn winds from the south
cloudy
This is the first report from the
field from the third ANSLOPE cruise on board the R/V
Nathaniel B. Palmer. Nearly two weeks ago we left Lyttelton,
New Zealand to steam towards Antarctica. (read previous AnSlope
Report and previous CORC/ARCHES
Report From the Field.)
It took us about a week to reach
the ice. As on previous cruises to these southern waters
we had to cross the windiest and roughest part of the
world's oceans. With everything safely tied to tables,
walls and floors the huge waves were not able to cause
any problems for our equipment. Unfortunately, this
could not be said for the stomachs of some of us.
These stomachs got the prospect
of additional trouble shortly before the cruise, when
we were told that the ship would have to return to
harbor after about 30 days at sea. Originally, we had
planned to stay out at sea for the whole 60 days of
ship time dedicated to our project. That means that
we have to cross the rough part of the ocean not twice
(down to Antarctica and back) but four times.
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| The
R/V Nathaniel B. Palmer docked in Lyttelton,
New Zealand. |
This development had quite an impact
on our plans. Though we are here in the southern hemisphere's
spring season, the ice from last winter has not yet
melted. In fact it is now just one or two months after
the ice had reached its maximum winterly extent. Our
original work area at the continental shelf break of
the Ross Sea lies about 400 nautical miles (440 miles)
inside the ice. It would likely take more than four
days to cross. That means that from a 30-day cruise
leg out at sea, only 6 days would be spent in the work
area.
We thus decided to
divert to an area further west in which we could observe
similar processes as in the Ross Sea but which is located
only 50 nautical miles within the ice. We hope that
by the time of the second cruise leg the ice in the
Ross Sea has melted enough to try to get to the original
work area.
Five days ago we arrived off the
George V Coast, our new work area. Since then we have
been working round the clock measuring physical and
chemical properties of the ocean over the continental
slope. The data we are collecting will help us to understand
what exactly happens when dense water that is formed
further on the continental shelf spills over the continental
shelf break into the deep part of the Southern Ocean.
Later during the cruise we will report more on this.
Apart from participants in the ANSLOPE
project we also have wildlife and sea ice observers
on board. They are studying possible connections between
sea ice type and wildlife. We will report more on them
in our next report from the field.
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