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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