Antarctic ice loss increased dramatically

           Antarctic ice loss increased dramatically

 You may have heard about global warming. It seems that in the last 100 years the earth’s temperature has increased about half a degree Celsius. This may not sound like much, but even half a degree can have an effect on our planet. This higher temperature may be causing some floatingicebergs to melt, but this will not make the oceans rise. Icebergs are large floating chunks of ice. In order to float, the iceberg displaces a volume of water that has a weight equal to that of the iceberg.

Recently in one study it is found that Melting of floating ice shelves around the continent is accelerating, potentially unlocking extra sea level rise from larger ice sheets jammed behind them. The ice around the edge of Antarctica is melting faster than previously thought, potentially unlocking metres of sea-level rise in the long-term, researchers have warned.

A team of US scientists looked at 18 years’ worth of satellite data and found the floating ice shelves that skirt the continent are losing 310km3 of ice every year. One shelf lost 18% of its thickness during the period.

The loss of ice shelves does not contribute much directly to sea level rise. But they act like a cork in a bottle at the point where glaciers meet the sea – jamming the flow of ice from the massive ice sheets of east and west Antarctica.

Over the past decade the loss of ice shelf volume in Antarctica increased from 25km3 to 310km3 every year.

It is unclear whether the loss of ice is directly related to man-made climate change or a cyclical change in ocean currents. But the extra sea level rise from ice sheets will exacerbate the rise caused by the expansion of oceans as the world warms.

Professor David Vaughan, director of science at BAS, said the findings would help scientists to make more accurate predictions about future sea level rise.

The western coast ice shelves contributed the majority of the ice loss. The rate of loss increased by 70% in the last decade. Two shelves in this region could completely disappear within a century. Conversely, there were some areas in east Antarctica where the shelves stayed stable or grew slightly. Vaughan said the regional variations were predicted by previous studies.

Holland said it was important not to confuse floating ice sheets, which can be up to 2km thick, with the much thinner sea ice. The one metre thick layer of sea ice around Antarctica has been expanding in recent decades, which some scientists think is because of increasing polar winds, which push the ice further out.

Source:www.theguardian.com/environment/2015/mar/26/collapse-antarcticas-glaciers-ice-melt-sooner-than-thought-scientists-warn