“Antarctica”, a home to the world's mightiest store of ice is affected by Global Warming. throughout, evidently said by the Scientists They also declared the fact that the average temperature across the great southern continent has been rising for the last half century and the finger of blame points at the greenhouse effect.
Any significant flow of Antarctica could drown many coastal cities and delta regions. Bigger than Australia, Antarctica holds enough ice to raise global sea levels by 57 meters.
Just a small sliver of ice is holding a giant Antarctic ice shelf in place, with experts saying that it will collapse any time now. The Wilkins Ice Shelf is the latest victim of global warming, set to join nine other shelves that already have been be lost around the Antarctic peninsula in the past 50 years.A general belief is that the icy slabs have even cooled slightly and possibly thickened, partly in response to the chilling seasonal effects of the ozone hole over the South Pole.
It has been calculated that the West Antarctica has been warming by 0.17 ºC per decade over the past 50 years. This is even more than the Peninsula, where the average rise is estimated as 0.11 ºC per decade. As the result of hole in the ozone layer there has indeed been some cooling seen in East Antarctica, but this was mainly due to the season of autumn, There was also a period of strong cooling between 1970 and 2000.But, overall and when calculated over 50 years, East Antarctica has warmed too – by an average of 0.1 ºC per decade,
The sense of cooling in East Antarctica, is based mainly on the period of 1970 to 2000 and it's warmed since then although we don't have a lot of data for the most recent period .The work is based on a 25-year archive of observations by satellites measuring the intensity of infrared light radiated by the snow pack. These were stayed by data from automated weather stations deployed around the Antarctic coast since 1957.
Antarctic ozone hole bigger than ever
The hole could be eliminated by the middle of this century. If that happens, all of Antarctica could begin warming on a par with the rest of the world. The West Antarctic ice sheet, which holds enough ice to boost global sea levels by up to six metres, lies at an average height of about 1,800 metres. The East Antarctic ice sheet, divided from West Antarctica by a mountain chain, has an average elevation of around 3,000 m, which makes -it not only bigger but also colder.
According to the united Nations weather agency, the hole in the ozone layer above Antarctica has striked the record size logged six years ago.The World Meteorological Organisation (WMO) said that data from the U.S. space agency NASA showed that the hole in the atmospheric layer that guards the world against dangerous ultraviolet light had grown to 29.5 million square kilometres.The hole was recorded by NASA on September 25, and just beat the previous record of 29.4 million square kilometers which was set in September 2000.
There is a growing body of evidence that 2006 will be a bad year for the Antarctic ozone layer, with scientists agreeing that the hole has reached record proportions. This is largely due to temperatures above Antarctica reaching the lowest recorded levels since 1979.The hole measured by NASA was slightly bigger than the 28 million square kilometers announced by the European Space Agency (ESA) earlier this week. However, the ESA also discovered other records: a loss of 40 million tones, exceeding the previous high of 39 million tones set in 2000.
Ozone loss is calculated by measuring the area and depth of the ozone hole in the stratosphere, about 25 kilometers above the Earth's surface. Ozone, a molecule of oxygen, filters out dangerous ultraviolet rays from the Sun that damage vegetation and can cause skin cancer and cataracts. Scientists say the layer has been badly damaged by man-made chemicals, especially by chlorine and chlorofluorocarbons (CFCs), which are used as aerosol gases and refrigerants.
The chemical reaction that thins ozone reaches its peak with colder high altitude temperatures in the southern hemisphere winter, normally in late August to October. CFCs and other ozone enemies were controlled by an international treaty signed 19 years ago. However large ozone holes are expected to persist for the next couple of decades because of the amount of pollutants already stored in the atmosphere. According to officials from the WMO and the UN Environment Program me (UNEP), the ozone layer over the Antarctic now looks set to be replenished 15 years later than originally predicted, setting the date back to 2065.
While ozone in the stratosphere is protective, at ground level a chemical reaction with exhaust fumes and sunlight makes ozone a pollutant that can be dangerous for people with respiratory or heart problems.