Ice sheets melting faster than predicted

... causing a greater rate of sea-level rise:

The pace at which the Greenland and Antarctic ice sheets are melting is "accelerating rapidly" and raising the global sea level, according to findings of a study financed by NASA.

The findings suggest that the ice sheets - more so than ice loss from earth's mountain glaciers and ice caps - have become "the dominant contributor to global sea level rise, much sooner than model forecasts have predicted".

This study, published on Tuesday, the longest to date examining changes to polar ice sheet mass, combined two decades of monthly satellite measurements with regional atmospheric climate model data to study changes in mass.

Global Warning Climate Change Energy

Melt opens Northwest Passage to science

I'm all for science, but I would have preferred the Northwest Passage frozen.

clipped from news.bbc.co.uk On Monday, the Canadian Coast Guard is preparing to send one its research vessels, the Amundsen, through the Northwest Passage with about 40 scientists on board. Equipped with a remotely operated robot submarine and a sonar system, the ship will undertake a detailed survey of the sea-bed - essential if the waterway is to become more open to commercial shipping. 'Northwest Passage opens' Sailing the passage Researchers on board also hope to study the changing patterns of the ice - not only the ice that grows and retreats with the seasons but also the far thicker multi-year ice which drifts with the Arctic currents and poses the most serious threat to any vessels. A British team on board will study the sediment on the sea-bed to hunt for a chemical record of changes in the ice stretching back for the past thousand years - a vital task to help understand the likely rate of change in the future. BBC News will join the ship for its journey through the Northwest Passage.

Greenland's DNA reveals green past

Erik the Red, who settled in Greenland 1000 years ago, named it to lure more settlers, although a small area not covered by ice would then have been very green.

While an admirable marketing tactic, Erick was half a million years (give or take a thousand), behind the times.

clipped from www.smh.com.au THE oldest DNA found on earth has been collected from under a kilometre of ice in Greenland, revealing that the frozen island really was once green. Half a million years ago Greenland was covered by lush forests filled with butterflies, moths and the ancestors of beetles, flies and spiders. The discovery of ancient DNA from a warm period half a million years ago suggests that ice on top of the ancient forest did not melt as believed during the last warm period, 116,000 to 130,000 years ago, when temperatures were 5 degrees higher than today. If it had, the remains of the ancient trees and insects would have been replaced by new flora and fauna. "If our data is correct, this means that the southern Greenland ice cap is more stable than previously thought," said Professor Willerslev, whose team's findings are published today in the journal Science. Global Warning Climate Change Energy

Manhattan ice island found 50 kms offshore

The first major ice-shelf calving in 25 years, in 2005, from the Ayles Ice Shelf in the Arctic, is slightly thicker than anticipated; Between 42-45m (138-148ft) - the equivalent of the height of a 10-storey building.

That's the good news.

clipped from news.bbc.co.uk Scientists in the Arctic have just carried out the first research on a huge iceberg the size of Manhattan. Some 16km long and 5km wide (10x3 miles), Ayles Ice Island broke away from the Canadian Arctic coast in 2005, but has only recently been identified. Researchers have now landed on the giant berg with a BBC team and planted a tracking beacon on its surface. This will allow the island's progress to be monitored as currents push it around the Arctic Ocean. The team wants to know why this Ice Island formed Tracking the island For 3,000 years, this colossal block of ice was securely fixed to the coast as part of the Ayles Ice Shelf - but now it is drifting free. Its current location is about 600km (400 miles) from the North Pole, in what is one of the fastest warming regions on Earth. Global Warning Climate Change

Computers can't keep up with melting Arctic

Out of an exercise mapping real-world observations to computer climate models comes news that global warming is more accelerated than the scientific consensus holds.

Ted Scambos of the National Snow and Ice Data Center (NSIDC) at the University of Colorado co-authored the latest study of Arctic ice melt, published in the journal Geophysical Research Letters, with other scientists from NSIDC and from the National Center for Atmospheric Research (NCAR), also in Boulder, Colorado.

This is the third piece of recent evidence that the IPCC forecasts err on the conservative side.

clipped from news.bbc.co.uk

Arctic melt faster than forecast

By Richard Black Environment correspondent, BBC News website Arctic summer ice has been shrinking by about 9% per decade Arctic ice is melting faster than computer models of climate calculate, according to a group of US researchers. Since 1979, the Arctic has been losing summer ice at about 9% per decade, but models on average produce a melting rate less than half that figure. The scientists suggest forecasts from the Intergovernmental Panel on Climate Change (IPCC) may be too cautious. The latest observations indicate that Arctic summers could be ice-free by the middle of the century.