ICECAPS MELT January 9, 2008Posted by wmmbb in Environment.
The icecaps continue to melt. As The New York Times reports they represent huge sources of water, enough on the current trend to raise the sea level in this century by two feet – some will get their toes wet. One question might then be, since the process seems now to be irreversible, is how do we as human beings purpose to change: do we weigh for the full implications, or do we anticipate and forestall the worst case outcomes, or do we believe, as some have proposed that since it will affect others, it does not matter?
Melted ice water flowing through the landscape. (Uriel Sinai/Getty Images via NYT)
While the dome of ice of the Greenland Ice Cap may seem impregnable when flying over it a different impression is gained writes Andrew C Revkin:
Along the flanks in spring and summer, however, the picture is very different. For a lengthening string of warm years, a lacework of blue lakes and rivulets of meltwater have been spreading ever higher on the ice cap. The melting surface darkens, absorbing up to four times as much energy from the sun as unmelted snow, which reflects sunlight. Natural drainpipes called moulins carry water from the surface into the depths, in some places reaching bedrock. The process slightly, but measurably, lubricates and accelerates the grinding passage of ice toward the sea.
Most important, many glaciologists say, is the breakup of huge semisubmerged clots of ice where some large Greenland glaciers, particularly along the west coast, squeeze through fjords as they meet the warming ocean. As these passages have cleared, this has sharply accelerated the flow of many of these creeping, corrugated, frozen rivers.
All of these changes have many glaciologists “a little nervous these days — shell-shocked,” said Ted Scambos, the lead scientist at the National Snow and Ice Data Center in Boulder, Colo., and a veteran of both Greenland and Antarctic studies.
Some fear that the rise in seas in a warming world could be much greater than the upper estimate of about two feet in this century made by the Intergovernmental Panel on Climate Change last year. (Seas rose less than a foot in the 20th century.) The panel’s assessment did not include factors known to contribute to ice flows but not understood well enough to estimate with confidence. All the panel could say was, “Larger values cannot be excluded.”
A scientific scramble is under way to clarify whether the erosion of the world’s most vulnerable ice sheets, in Greenland and West Antarctica, can continue to accelerate. The effort involves field and satellite analyses and sifting for clues from past warm periods, including the last warm span between ice ages, which peaked about 125,000 years ago and had sea levels 12 to 16 feet higher than today’s.
So it looks like global climate change is happening. We do not have to guess that the losers in the zero sum game of consequences will be those less responsible in the first place, and less powerful in their new less secure place. Why was such damage down to the Earth, and then to its people?
POSTSCRIPT: 15 January 2008.
Robyn Williams talks with Dr Tim Flannery on the ABC program, Talking Science. They discuss global warming, the right wing sceptics, and greenhouse gas emissions. The programs lasts for almost 27 minutes. Flannery has an optimistic view that the transition from a coal-based to a “solar economy” can happen with net positive outcomes.