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Open access. First published: 1 January Copyright by the American Geophysical Union. Book Series: Antarctic Research Series. Since the s, glaciologists working in Antarctica have gone from strength to strength, but they now have even more tools at their disposal.
The most significant of these being satellites provide new perspectives at a continental-scale and previously unimagined precision. In the last ten years, glaciologists have ceased, simply to make uncertain assessments of whether the ice sheet in balance or not. Science : — At the same time, our research goals have changed, we are now focused on understanding the specific causes of observed changes and predicting their future. These changes may appear subtle, but their effects may eventually be felt across the world.
The Antarctic ice sheet is the single most important control on global sea level and changes in the volume of the Antarctic ice sheet may one day affect national economies and the lives of countless individuals living in coastal communities. The importance of the Antarctic ice sheet within the climate system and as a herald of global change is established.
Antarctic glaciology not only promises to be exciting for the glaciologist but also central to issues of policy-making in the coming century. The Discovery Investigations of the s provided a compelling description of the main elements of the Southern Ocean circulation. Over the intervening years, this has been extended to include ideas on ocean dynamics based on physical principles.
In the modern description, the Southern Ocean has two main circulations that are intimately linked: a zonal west-east circumpolar circulation and a meridional north-south overturning circulation. The Antarctic Circumpolar Current transports around million cubic metres per second west to east around Antarctica. This zonal circulation connects the Atlantic, Indian and Pacific Oceans, transferring and blending water masses and properties from one ocean basin to another. For the meridional circulation, a key feature is the ascent of waters from depths of around 2, metres north of the Antarctic Circumpolar Current to the surface south of the Current.
In so doing, this circulation connects deep ocean layers directly to the atmosphere. The circumpolar zonal currents are not stable: meanders grow and separate, creating eddies and these eddies are critical to the dynamics of the Southern Ocean, linking the zonal circumpolar and meridional circulations. In the Discovery sailed into an ocean that was almost totally unknown biologically.
- Fateful Adventures of the Good Soldier Svejk During The World War, Books Three & Four;
- WoRMS - World Register of Marine Species - Haloptilus setuliger Tanaka, .
- The Strange Case of Ermine de Reims : A Medieval Woman Between Demons and Saints;
- Antarctic Treaty database.
Even so, its living resources of seals had been extensively hunted almost to the point of extinction. Exploitation of the whales was about to begin. The results were worked up within six years, and paved the way for the next century of research. The ultimate target was to provide the scientific basis for the sustainable management of the Southern Ocean especially the whale stocks. This paper summarizes the knowledge base at the start of the expedition and how the various strands of research became woven into our understanding of the biological oceanography of the Southern Ocean.
The science has been both technology driven and technology limited. It failed to convince decision-makers in time to prevent the gross overexploitation of the whales, but the Antarctic Treaty now provides a framework of protection.
Antarctica - Bulgarian Antarctic Institute
However, within the last two decades we have come to realize that it is not just whales that are at risk, and that the remoteness of the Southern Ocean is proving no protection against the pervasiveness of anthropogenic influences. Antarctic krill, which in the era of Discovery Investigations had been studied as the whale food, now became a target for commercial fishing along with some fin fish species.
Major concerns were expressed at the potential difficulties that might arise, not just for krill but also dependent species, should over-fishing on krill occur. Implementing an ecosystem approach by CCAMLR, the first to be included in any fisheries convention, has provided challenges. More recently the questions of surveillance and monitoring of the fleets in the lucrative toothfish fishery has been the major concern.
Developments in fishing, monitoring and the provision of scientific advice for management are discussed. Early explorers and sealers took home from the Southern Ocean tales of tempests, huge waves and massive icebergs.
Many recorded in their logbooks and narratives observations of wind, weather and sea state. Meteorological measurements were made on some early voyages but were often of doubtful quality. Not until the s were reliable meteorological observations made near the Antarctic continent. From onwards, bases were established on the Antarctic continent and meteorological observing programmes organized.
Extremely strong winds were discovered. Data sets of climatological value became available and data from aloft were obtained. After the First World War, wireless telegraphy was used increasingly to broadcast observations from ships and shore bases to distant analysis centres. During the Second International Polar Year, thousands of meteorological observations were made aboard ships on the Southern Ocean. Research stations and the International Antarctic Analysis Centre were established. Weather satellites, automatic weather stations, global telecommunication networks and powerful computers revolutionized Antarctic meteorology and climatology.
Great advances have been made in recent years in our understanding of the weather of the Antarctic and how the climate of the continent varies on a range of time-scales.