The Southern Ocean Marine Ecosystem is, in many respects, unique. It has an inner ring around the Antarctic continent with a sea-ice dominated regime, followed by a very large area that is seasonally iced and deiced and finally, an outer ring of open oceanic water. Because of physical conditions, the surface water is very much isolated from the rest of the world oceans, while intermediate and deep water is in open communication with these. There is generally high primary production in the surface water, particularly close to the ice-edge during the time of ice retreat, but, in general, nutrients in the water are not depleted. What limits primary production is still not understood, but contributing factors are deep mixing, grazing by zooplankton and possibly lack of some micronutrients (e.g. iron). The system sustains a secondary production of enormous proportions, notably of one species of krill, the Antarctic krill (Euphausia superba), which has a total estimated biomass of somewhere between 650 and 1000 million tons (which is more than double the biomass of the human population on earth). The system is physically highly variable both seasonally and interannually-yet it is predictable within limits, and it is mature enough for the biota to have adapted to the harsh conditions. Because of these special conditions and the important role of the polar seas in the global climate, the Scientific Steering Committee of the International Global Ocean Ecosystem Dynamics (SSC of GLOBEC International) decided that the Southern Ocean is a key geographical area for studies of the processes that govern and influence secondary production.

The SSC of GLOBEC International gratefully acknowledges the kind invitation to hold a meeting of its Southern Ocean Planning Group at the Center for Coastal Physical Oceanography of the Old Dominion University in Norfolk, Virginia, USA. The meeting was sponsored by U.S. GLOBEC for U.S. participants and by SCOR for many of the international members of the Group. Others were paid for their participation by sources in their own countries. The Meeting took place under excellent conditions and ground service from the host institution.

Jarl-Ove Stromberg, International GLOBEC SSC