The ozone hole
The discovery by the British Antarctic Survey of the Antarctic ozone hole provided an early warning of the dangerous thinning of the ozone layer worldwide, and spurred international efforts to curb the production of CFCs. If the provisions of the Montreal Protocol on Substances that Deplete the Ozone Layer of 1987 are revised, strengthened and followed, there is a reasonable prospect that the Antarctic ozone hole will permanently repair itself, but not before the next appearance of Halley's comet (in the year 2061)!
Earth's past climate
The ice sheet preserves not only the traces of heavy metals and organic toxins carried into the Antarctic from the inhabited parts of the world but also - frozen into bubbles - samples of previous atmospheres over the past 500,000 years. The bubbles carry information about the climate of the past.
The delicate ecosystem
In the Southern Ocean around the continent increasing levels of fishing threaten the stability of the marine ecosystem. Rising tourist numbers increase the risks of environmental damage at coastal sites. Understanding these risks is essential for sustainability, and to ensure that our management is based on sound scientific data.
Antarctica's contribution to sea level rise
Global climate model predictions of how the Antarctic climate may change over the next 100 years differ in detail from model to model. Most models indicate relatively modest temperature rises around Antarctica over the next 50 years and, over this time period, snowfall is likely to increase over the continent, and this effect may partially offset the rise in sea level. However, there are parts of the continent Antarctic Peninsula and West Antarctic Ice Sheet
where recent observations have indicated an ongoing loss of ice. The mechanisms responsible for those losses are the focus of ongoing research, but there is a significant possibility that they could accelerate over the next 100 years and mean that the Antarctic as a whole becomes a significant contributor to sea level rise, adding to the other sources; thermal expansion of the oceans and melting of icecaps and glaciers elsewhere in the world.