Thursday, January 16, 2014

Irreversible Meltdown In Antarctica

A study in the journal Nature Climate Change concludes that one of the largest glaciers in Antarctica has begun to irreversibly melt. The Pine Island glacier has entered a "phase of self-sustained retreat and will irreversibly decline" concludes Gael Durand, a glaciologist from Grenoble Alps University. He was interviewed by Australian Broadcasting Corporation.  The Pine Island glacier is the single biggest Antarctic contributor to sea-level rise and accounts for one-forth of the ice melt from the West Antarctic Ice Sheet.  Alone, it could raise sea level one centimeter in the next twenty years; if the entire ice sheet were to retreat from the sea it could raise sea level a catastrophic 10 feet or more, making many coastal cities uninhabitable.  The glacier's grounding line--where it meets the sea--will probably retreat 40 kilometers inland said researchers.  It has been loosing 20 billion tons of ice a year for the last twenty years, but the rate will increase to something nearer 100 billion tons a year in the coming decades.
Emperors nesting inland @ Jason Peninsula
This new study and others show that previous conclusions about Antarctic ice melt were too simplistic, based only on ocean warming. Not an unusual development as more data is collected and analyzed about a particular phenomenon capturing scientific attention; it's how science works. New results are showing the Antarctic ice sheet is more susceptible to climatic conditions occurring elsewhere on Earth. For example during the La NiƱa event in 2012, the melting ice flows decreased by half. But such a condition is seen as temporary and not something that will halt or reverse the retreat of Pine Island's glacier or other ice shelves around the Antarctic Peninsula. Emperor penguins, those masters of survival, are now seen nesting inland, atop ice shelves which they must climb up tens of meters to reach from the sea [photo].