Antarctic Climate Change

Scientists at NASA ran a computer model in 2004 that indicated that the South Pole would enter a period of warming for the next 50 years. Because the use of ozone-depleting chemicals has been banned for several years, the hole in the ozone layer is repairing itself as ozone levels return to normal. This, in turn, will cause dominant airflow patterns in the atmosphere that weaken the westerly winds and warm the air temperature.

The model was run several times comparing the oceans to the atmosphere. Each time the model began with the year 1945 and ran through the year 2055. The results were encouraging—the results for 1945 to the present matched the actual records very well. The values that were entered to reflect greenhouse gases were taken from a combination of 1999 data and the IPCC's mid-range estimates of future emissions.

The results of the model were that the most significant impacts in Antarctica would be the melting of the ice sheets and their subsequent sliding into the ocean, making sea levels rise. NASA scientists reported thawed ice sheets the size of the state of Rhode Island have already col lapsed into the ocean during warming—partially brought on by stronger westerly winds in the area that heat the peninsulas as they blow over them.

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