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Antarctic Research 1993 |
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Austral summer 1993The oceans surrounding the
Antarctica represent a fascinating challenge for the experimentally minded
marine biologist. The life here has adapted to extremely low temperature,
harsh weather conditions and long winters. In summer, however, the beauty of
these regions is overwhelming. For plankton ecology, a special feature of these waters is the high concentration of phosphorus and nitrogen, which usually are completely depleted under summer conditions elsewhere. The paradox of the high nutrient, low productive ocean was first noted by the Norwegian oceanographer Gran, and has been the subject of intensive studies. Some of the most important studies of the paradox were conducted during the nineties. A very comprehensive text on the whole story can found in a review by the Dutch oceanographer Hein de Baar (de Baar (1998) von Liebig’s law of the minimum and plankton ecology (1899-1991) Progress in Oceanography 33:347-386). In 1993 the Trondheim Carbon
Cycle Group went on their first expedition to the Southern Ocean. Prof.
Myklestad and myself were given quite adequate laboratory conditions on board
the R/V Polarbjørn, as a part of the Nordic Antarctic expedition that year. We
brought equipment for measuring concentrations of dissolved organic carbon
(DOC), primary production both in the particulate and dissolved form, and
bacterial biomass and production rate. We had a great voyage. The vessel was
not built for comfort, but for staying afloat under rough conditions of sea
and in the ice. R/V Polarbjørn is only 55m long, she is ice enforced in every
possible way, but she is not an icebreaker. The round shape that is necessary
to avoid being crushed by the force of sea-ice makes the ship a severe
roller, she is not unlike the famous wooden ship Fram that carried Fridjof Nansen to the Polar Ocean in 1893-1896.
Fram also knew how to roll. |
R/V Polarbjørn
stuck in the ice off Dronning Maud land in February
1993 |
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Sverre Myklestad measuring primary production |
We got all the adventure we had expected, we had waves like we had never seen
before from Cape Town to the coast of the Antarctica, we got the stuck in the
ice for a full week. The grip of the ice was so firm that we could do very
nice microscopy work on board, this procedure is usually severely hindered in
open sea conditions. Sampling of the ocean below was slightly hampered by the
ice, but we could use some sampling equipment from the heck, where some water
was kept open by the propeller.
When the storm faded and the direction of the wind turned from northernly to
the normal southernly, the ice gave way and we got out. We returned to the
same waters in 2001, and now in 2005 we look forward to the International
Polar Year.
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