Meltwater could prove problematic. (Picture from: http://www.newscientist.com/) |
Melting of ice in excess is bad for the sea. Fresh water from melting icebergs in the Arctic island of Greenland in not only add in sea level, but also interfere with the function of the sea.
"Overflow of fresh water would disrupt ocean currents and reduces the ocean's ability to absorb carbon from the atmosphere," said Jonathan Bamber, researchers from the University of Bristol, UK.
Polar Ocean including the most important carbon sink on Earth. The oceans are cold temperature throughout the year is to absorb carbon dioxide from the atmosphere and trap him in the bottom of the sea. Carbon content can change with the flow of fresh water into the sea.
Bamber and his colleagues note, Greenland telatv lost most of its ice mass. The volume of fresh water from Greenland into the Atlantic Ocean has increased in recent decades. Through reconstruction in 1958-2010, it is known that the volume of ice in the island decreases rapidly from the early 1990s, especially in the south end of the island.
On Sunday, Sept. 16, 2012, Arctic sea-ice extent set a new record low that far surpasses the previous low set in 2007. (Picture from: http://www.newscientist.com/) |
Nearly half of the southeast Greenland ice also melted in less than 20 years. "What remains a mystery is how much fresh water that slid into the ocean," said Bamber.
Ruth Curry of the Woods Hole Oceanographic Institution in Massachusetts, USA, said that the influx of fresh water into the North Atlantic ocean currents could weaken the Atlantic Meridional overturning Circulation (AMOC), the of ocean belt currents that carry the warm tropical water to northern Europe.
AMOC changes made lake in Europe, which should be cooler-warmer in the coming decades. "All blown out of proportion," said Ruth.
Curry said the freshwater Greenland ice melt results are likely to remain on the surface of the ocean. Therefore, the weakened AMOC will slow in bringing fresh water to the ocean bottom. This means that fresh water will remain on the surface even after absorbing carbon dioxide to the point of saturation.
In effect, no fresh water is replaced by air-sea carbon dioxide beneath. Though water from the deep sea should be able to absorb more greenhouse gases.
"If AMOC slowed, seawater ability to absorb carbon dioxide will also slow down," said Curry. The weakening of the carbon sequestration could accelerate global warming.
This finding reinforced the analysis of computer models conducted Markus Buehler with Zhao Qin, two scientists from the Massachusetts Institute of Technology (MIT). They concluded that carbon dioxide can damage the glaciers that have been under pressure of global warming.
"Carbon dioxide is trapped in the crevices of the ice can weaken the ice," said Buehler, who studies mechanical properties of cracks, from spider silk to the bone.
Their research focuses on nanoscale objects, to see the bond between the molecules and atoms, He and Qin began a study of breakaway icebergs of Greenland, which doubled the size of Manhattan, from a single broken bond. They investigated what happens when the ice broke. *** [LIVESCIENCE | NEWSCIENTIST | MAHARDIKA SATRIA HADI | KORAN TEMPO 4034]
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