1. Introduction

The Antarctic marine food web is unique in that it is characterized by dependence on a single key species, Antarctic krill, and by dependence of many of the components of this food web on sea-ice during some or all of their life history. These unique characteristics make this ecosystem especially vulnerable to changes in environmental conditions, or to resource exploitation. Predictions of the Antarctic marine food web responses to environmental variability and climate change first require understanding and documentation of the cycles of natural population variability.

The International Global Ocean Eco-system Dynamics (GLOBEC) programme identified the Southern Ocean as a potential research site. It was recognized that the unique characteristics of the Antarctic marine food web make the Southern Ocean an ideal environment in which to test many of the GLOBEC core hypotheses that consider the effects of variability in the physical environment on population dynamics. In addition to studies relating to the GLOBEC core hypotheses, it was recommended that a Southern Ocean GLOBEC programme include studies of:

  1. regional differences in overwintering strategies of Antarctic krill in relation to the physical environment;
  2. population dynamics of selected zooplankton species, both sea-ice related and planktonic species;
  3. population dynamics of major krill predators, both ice-based and pelagic species; and
  4. the effects of UV-B radiation on zooplankton dynamics.

The international GLOBEC Science Steering Committee (SSC) further recommended that a meeting be held to define the scientific rationale and to begin the development of an implementation plan for an international Southern Ocean GLOBEC programme.

This latter recommendation led to a meeting that was held, under the auspices of the international GLOBEC programme, in Norfolk, Virginia, June 15-17, 1993. This meeting was attended by 26 scientists who represented 9 nations with interests in Antarctic programmes, and the Intergovernmental Oceanographic Commission (IOC). The goals of this meeting were to define the key questions and framework to be used as a basis for the development of an implementation plan for an international Southern Ocean GLOBEC programme. This report presents a summary of the discussions and recommendations from the meeting. It is anticipated that the recommendations from this meeting will provide the basis for a second meeting which will develop an implementation plan for a Southern Ocean GLOBEC programme.

The following section provides some background information on previous GLOBEC meetings that are relevant to the development of a Southern Ocean programme. In particular the recommendations from a U.S. GLOBEC Southern Ocean meeting held in 1991 are summarized. Section 3 presents a summary of the key questions and recommendations arising from the meeting and section 4. provides the working group reports from which the key questions were extracted. Section 5 lists the international programmes and connections that are important and necessary components of an international Southern Ocean GLOBEC initiative.