The Ozone hole
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Scientists from across the World have agreed the Earth is heating up. The average increase in temperature is about .5 degrees Celsius in the past 50 years. The Antarctic Peninsula’s temperature has risen 3 times that amount, 1.5 degrees Celsius. This has tremendous implications for all wildlife in the area. In the past 5 years there has been reduced sea ice coverage in the winter months, and the ice sheets have started to disintegrate at an increasing rate. Satellite imagery has helped to document the changes in ice extent as well as track the movement of icebergs when they break off from ice sheets. Recent missions have also been tasked with measuring the thickness of the continental ice sheets using radar remote sensing.

Another effect of the increased temperatures is an increase in snowfall. Warmer air can hold more water, and therefore rates of snowfall are likely to increase. This can cause problems for penguins who need nesting spots on bare ground.

Given that krill are the keystone species of the ecosystem, and krill are dependent on microscopic phytoplankton, and the phytoplankton are dependent on ice, a decrease in ice could spell disaster for the entire food web.

Other changes that have documented over Antarctica is the hole in the ozone layer. The hole is believed to be caused by chloroflorocarbons (CFCs). Once these man-made chemicals enter the high atmosphere, they destroy ozone. This has led to the hole in the ozone layer that increases the amount of ultraviolet radiation (UV). This has been shown to cause increasing amounts of cases of skin cancer, especially at high southern latitudes. The increases in UV exposure have also shown to be detrimental to wildlife.

Since the Montreal Protocol was signed, banning the production of CFCs, the hole in the ozone layer has begun to shrink. Given this promising example, it is now thought that by reducing the amount of carbon dioxide and other greenhouse gases in the atmosphere, the warming trend that is currently happening will be reversed. Check out http://www.undoit.org/ for more information