Floating Ice, Sinking Cities?

"'Moulin' is the name for a giant hole in a glacier through which millions of gallons of melt water cascade through to the rock below. The water has the effect of lubricating the glaciers so they move at three times the rate that they did previously.

Some of [the] moulins in Greenland are so big that they run on the scale of Niagra Falls. But it is not the lack of sea ice that worries scientists and should be of serious concern to the inhabitants of coastal zones across the world. Cities like New York and states like Florida are in the front line.

Scientists know this already, but just to give you some idea of the problem, the Greenland ice cap is melting at such a fast rate it is triggering earthquakes as pieces of ice several cubic kilometres in size break up.

Scientists say the acceleration of melting and subsequent speeding up of giant glaciers could be catastrophic in terms of sea level rise and make previous predictions published this year by the Intergovernmental Panel on Climate Change (IPCC) far too low.

[N]ewly invented ice penetrating radar showed that the melt water was pouring through to the bottom of the glacier creating a melt water lake 500 metres deep causing the glacier to "float" on land.

If all of Greenland melts, something we were previously assured would take thousands of years, but now could be hundreds, then sea level round the world would rise seven metres. That is without any contribution from the Antarctic, the glaciers of Alaska, the Rockies, the Himalayas, or the ocean water expanding as it warms.

So the talk of sea level rise should not be in centuries, it should be decades or perhaps even single years. For 10,000 years, during all of human civilisation sea level remained stable leading us to believe that coastlines remained roughly in the same place. A century ago the sea began to rise one millimetre a year, 20 years ago it had reached two millimetres and this century it has risen to 3 millimetres. This annual rise may not seem much but add hurricane storm surges and high tides and we are soon saying good bye to a lot of coastal settlements -- like the Big Apple."