Sea levels around Antarctica are rising faster than anywhere else in the southern ocean. The global average rise in ocean heights in the last 19 years has been 6cms, but the rise in seas around Antarctica is 2cms higher.
This seemingly counter-intuitive finding is certainly a consequence of melting ice in the Southern Ocean, but the connection with global warming is, for the moment, tenuous. The agency that is behind the rising sea levels is simply an excess of fresh water from melting glaciers − about 350 billion tons of it.
“Fresh water is less dense than salt water, and so in regions where an excess of fresh water has accumulated we expect a localized rise in sea level,” says Craig Rye, an oceanography researcher at of the University of Southampton in the UK, who, with colleagues, has published the findings in Nature Geoscience.
Partly because the oceans are warmer and are therefore expanding, and partly because the terrestrial glaciers are in retreat, global sea levels on average have crept up by about 3 millimeters a year. Waters off the Antarctic shelf seem to be gaining an additional 2mm a year.
The scientists studied satellite scans of a region of more than a million square kilometers to make their finding, and used ship-based studies of the Antarctic sea water to confirm that is has become less saline.
The melting of the Antarctic ice sheet –German scientists recently calculated that around 125 cubic kilometers of melt-water is running off the continent each year − and the thinning of the floating ice shelves is enough to explain the unexpected rise.
Computer model studies confirm the interpretation that the rise is happening because the southern seas have just got fresher. The consequences in the longer term are uncertain.
Rye, a postgraduate researcher, said: “The interaction between air, sea and ice in these seas is central to the stability of the Antarctic ice sheet and global sea levels, as well as other environmental processes, such as the generation of Antarctic bottom water, which cools and ventilates much of the global ocean abyss.”
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But I thought the massive earthquake in Chile in 2010 created shock waves and warm water in the Antarctic to augment the already warm currents coming up under the ice and melting it?Sep 09th, 2014 - 11:47 am 0
It seems this guy isn't quite up to speed.
Anyway, didn't the doomsayers from 'Global Warming', cross that out, 'Climate change' cross that out, 'The pause effect (world getting colder) will last ten years and then the rise will come back' [not as catchy is it?] predicted 200 miles rise in sea levels, or have I exaggerated it by the same amount as they lie?
Remember when Monsanto destroyed the pampa and soros moved in to frack and ruin the water supply?Sep 09th, 2014 - 04:05 pm 0
We need to stop this quickly,Sep 09th, 2014 - 06:34 pm 0
we suggest freezing Argentina...lol