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the Arctic, the Antarctic ice is mainly heaped up on land. It is not possible to traverse the Antarctic by submarine as it is in the Arctic. Frozen sea surrounds the landmass of the Antarctic. The extent of the frozen sea depends on the seasons, as the migrating penguins know well. Like any iceberg, this ice ledge is vulnerable to an increase in sea temperature and there is some secondary evidence that the sea in this region is getting slightly warmer. Over the past hundred years a large finger-like iceberg projecting north into the Southern Ocean, the Larsen B ice shelf, has progressively eroded and partially collapsed. Like the Larsen B shelf, the Wilkins shelf, which collapsed in 2008, was a gigantic iceberg jutting out from the Antarctic peninsular; it was believed to have been less than a thousand years old. These ice shelves are not land-based and were always in danger of disintegrating during warmer years as they extended further north from the coldest region around the South Pole, and are subject to the strong currents eroding their underwater base. Like all icebergs, they did not cause any recordable change in sea level when they collapsed and melted.

      It is difficult to be certain of the balance between new ice formation during the Antarctic winter and its loss during the warmer summer months, but satellite observations suggest that much of the Antarctic ice, especially that covering mountains in the eastern Antarctic, is getting more extensive. In this region the ice is now up to 3.2 kilometres (2 miles) thick. This is probably due more to an increase in rainfall than to any change in temperature.

      The story is more complex in the western Antarctic, where coastal ice appears to be subject to the same sliding motion as in Greenland. It is believed that this is an effect of the formation of rivers and lakes under the ice. The loss of ice from these coastal regions is slightly greater than the formation of new surface ice further inland, resulting in a small reduction in the total amount of ice in this region. It is probable that this part of Antarctica is relatively new and that it has been subject to changes in the past. Evidence from fossils found in ice-bore samples in this region suggests that much of Western Antarctica is geologically less than half a million years old, compared with the 20–30-million-year history of the rest of the Antarctica.

      The latest indications from the European satellites, ERS1 and ERS2, suggest that the total effect of the melting Arctic and Antarctic ice over the past nine to ten years has been to raise the ocean levels by 1.0mm a year. Although in geological terms, ten years is far too short a time in which to make any definitive judgement, it seems highly improbable that it will contribute more than a few centimetres to the height of the ocean by the end of the century.

      Although more studies are needed before we can be certain as to what is happening, it would seem that the net effect of the changes in the Antarctic ice cap on the global sea level is minimal. There is absolutely no evidence that the world is likely to be flooded in the immediate future because of the melting of the Antarctic ice. At present, most scientists agree that the Antarctic is not warming significantly. There is little to support the view that a rise in manmade CO₂ is causing any of the changes seen at the ice caps, many of which started long before the present rise in CO₂ levels. While it is possible that some colonies of penguins may have been affected by man’s intrusion into the frozen wilderness of the Antarctic, present evidence suggests the effect is small and that most colonies have increased in size.

      Although changes are happening around the fringes of the ice caps, all the evidence suggests that they have been occurring for many hundreds of years. Until we have more information on the extent and rate of these changes, their long-term significance remains uncertain. Whatever is happening, it is unlikely it will cause the rise in sea levels predicted by the alarmist propaganda and the end-of-the-world prophets of doom.

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