1. Antarctica and its surrounding Southern Ocean is one of the two large regional sinks of heat and is an area of intensive interaction between the atmosphere and the ocean. As such, it plays a significant role in the formation of global weather and climate. The comprehensive long-term series of high-quality meteorological data obtained on the land and at sea are necessary for better understanding of the atmospheric processes and climate variations in the Antarctic and their prediction. To meet the requirements for both meteorological services and research, including monitoring of climate change and environment, the WMO Antarctic activities concentrate on the promotion and coordination of meteorological programmes carried out in the Antarctic by nations and groups of nations and their interface with other WMO programmes in particular the World Weather Watch (WWW), the Global Atmosphere Watch (GAW), and the Global Climate Observing System (GCOS). In the framework of the World Climate Research Programme, WMO also participates in several research projects related to the Antarctic such as the International Programme for Antarctic Buoys and the Antarctic Ice-thickness Project. It is important to note that all these activities are carried out in close collaboration with other relevant international organizations, including the Antarctic Treaty Consultative Meeting (ATCM), the Scientific Committee on Antarctic Research (SCAR), the Intergovernmental Oceanographic Commission (IOC) and the Council of Managers of National Antarctic Programmes (COMNAP), in order to ensure a co-ordinated and cost-effective scientific and technical programme.

Although the WMO regional association structure formally terminates at latitude 60°S, it is recognized that coordination of Antarctic meteorological activities is a role for which WMO is uniquely suited. The Executive Council Working Group on Antarctic Meteorology was set up in 1964 to assume the functions which are essentially those attributed to the regional associations for the area between latitudes 60°S and 90°S. The working group is composed of members nominated by Permanent Representatives of countries which are Parties to the Antarctic Treaty and of Members which have not yet acceded to the Treaty but which have active meteorological programmes in the Antarctic. The main tasks of the working group are to coordinate the implementation of the WWW basic components in the Antarctic and to collaborate with other international organizations and programmes in operational and research activities in Antarctica.

2. One of the most significant achievement of the programme was the development of the observing and telecommunication networks in the Antarctic. The Antarctic Basic Synoptic Network (ABSN) is now an important element of the WWW Global Observing System (GOS). The operation and maintenance of the ABSN and the timely transmission of the observational data by means of the Global Telecommunication System (GTS) are essential to provide meteorological data for global weather analysis and prediction and for climate research. The preparation and distribution of meteorological analysis and prognosis for the Antarctic as well as warnings of dangerous conditions are important tasks of the Global Data-processing System (GDPS).

3. The current basic synoptic network in the Antarctic comprises 31 manned stations, including 12 upper-air stations and over 50 automatic weather stations (AWS). Automatic weather stations located in various places inside Antarctica provide an essential contribution to the maintenance of a meaningful meteorological network over the continent, and particularly over the interior ice sheet.

Meteorological data over the Southern Ocean are obtained in large part from voluntary observing ships. Substantial input into the data coverage over the ocean has been also provided through implementation of the International Programme for Antarctic Buoys (IPAB), which was established in Helsinki in mid-1994. One of the main aims of IPAB is to co-ordinate the development and maintenance of an optimum observational network with horizontal resolution about 500 km for near-surface meteorological and oceanographic data within the Antarctic sea ice zone, using drifting buoys and other appropriate in-situ data collection platforms.

In addition to observational opérations, spécial data-processing is carried out by five stations in Antarctica: Davis, McMurdo, Marambio, Rothera, and Presidente Frei to provide meteorological services for shipping, air navigation, local operations and research with support from WMCs and other WWW centres. They use large volumes of meteorological and oceanographic information provided by satellites through the network of ground receiving stations established in Antarctica.

Several Antarctic stations carry out systematic measurements of the amount of ozone in the atmosphere and its vertical distribution over the Antarctic. These measurements are made within the framework of the Global Atmosphere Watch with a view to assessing the ozone layer over the Antarctic and to determine the effect of its depletion on global change. On the basis of data received from the stations and satellites, the WMO Secretariat periodically issues an Antarctic Ozone Bulletin describing the state of the ozone layer over Antarctica each year during spring.

International research is continuing to improve our understanding of the processes that control the ozone layer. Ozone measurements carried out at Antarctic stations are essential because, in addition to their role in validation and calibration of satellite retrievals, they provide data on ozone concentration in the lower levels of the stratosphere where the largest global-scale trends are being observed.

4. There are many natural phenomena and processes in the Antarctic that have implications for global climate and its change. WMO intends to make an important contribution to investigations of the role of Antarctica in understanding climate change through the improvement and extension of the observational network, by the organization of efficient communication procedures to facilitate real-time data transmission as well as through the provision of processed data to meet the requirements for international research programmes.