blogspot visitor

10 oktober 2007

IJskappen smelten snel

By Paul Brown, AlterNet, October 10, 2007

The talk of sea level rise should not be in centuries, it should be decades or perhaps even single years. And coastal regions like New York and Florida are in the front line for devastation.

It is hard to shock journalists and at the same time leave them in awe of the power of nature. A group returning from a helicopter trip flying over, then landing on, the Greenland ice cap at the time of maximum ice melt last month were shaken. One shrugged and said:"It is too late already."

What they were all talking about was the moulins, not one moulin but hundreds, possibly thousands. "Moulin" is a word I had only just become familiar with. It 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 these moulins in Greenland are so big that they run on the scale of Niagra Falls. The scientists who accompanied these journalists on the trip were almost as alarmed. That is pretty significant because they are world experts on ice and Greenland in particular. We were visiting Ilulissat, Greenland, once a stronghold of Innuit hunters but now with so little ice that the dog sleds are in danger of falling through even in the depth of winter. 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.

Paul Brown was the environment correspondent for The Guardian newspaper for 16 years and has worked in newspaper journalism for more than 40 years. He has written extensively about climate change, population, biodiversity, pollution, energy, desertification, and ocean management, and is the author of several books on the environment.

Zie ook de blognotitie 'Afglijgevaar Zuidpoolijs' (17 mei 2007)

De eerst reacties op zijn op zijn zachtst gezegd skeptisch, zoals deze:

Here's a report from Ohio State University where they study Polar Ice at the Byrd Polar Research Center -

Scientists here are calibrating data from NASA’s Ice, Cloud, and land Elevation Satellite (ICESat), and using the satellite to study the ice streams that carry ice from the interior of the WAIS out to sea.

Early results of the study clearly show that all the ice streams of the WAIS have changed substantially in the last five years, but each in its own way, explained Bea Csatho, research scientist at Ohio State's Byrd Polar Research Center (BPRC) and head of the calibration project.

Csatho presented those early results on December 10 in a poster session at the American Geophysical Union meeting in San Francisco.

According to the ICESat data, some WAIS ice streams are thickening and others are thinning; some are flowing faster than before, and others are slowing down.

Waar een andere reactie prompt op inhaakt met:

"The interesting line in your post was that this research was found in a "poster session". I'm not sure most people would know what a poster session is but it is held for people whose research wasn't quite good enough to pass the blind review process for publication. Many times the conferences publicly state that the poster session pieces are not reviewed at all and that the sponsoring organization does not stand by the research. I would put as much credibility in this research as I would a caller to talk radio."

Geen opmerkingen:

Een reactie posten