Meanwhile the ice mass in East Antarctica has been roughly stable, with neither loss nor accumulation over the past decade.
Professor Jonathan Bamber at the University of Bristol and colleagues estimated the flux of ice from the ice sheet into the ocean from satellite data that cover 85% of Antarctica's coastline, which they compared with simulations of snow accumulation over the same period, obtained using a regional climate model.
They arrived at a best estimate of a loss of 132 billion tonnes of ice in 2006 from West Antarctica – up from about 83 billion tonnes in 1996 – and a loss of about 60 billion tonnes in 2006 from the Antarctic Peninsula.
Professor Bamber said: “To put these figures into perspective, four billion tons of ice is enough to provide drinking water for the whole of the UK population for one year."
The authors conclude that the Antarctic ice sheet mass budget is more complex than indicated by the evolution of its surface mass balance or climate-driven predictions.
Changes in glacier dynamics are significant and may in fact dominate the ice sheet mass budget. This conclusion is contrary to model simulations of the response of the ice sheet to future climate change, which conclude that it will grow due to increased snowfall.
The ice loss is concentrated at narrow glacier outlets with accelerating ice flow, which suggests that glacier flow has altered the mass balance of the entire ice sheet.
Over the 10 year time period of the survey, the ice sheet as a whole was certainly losing mass, and the mass loss increased by 75% during this time. Most of the mass loss is from the Amundsen Sea sector of West Antarctica and the northern tip of the Peninsula where it is driven by ongoing, pronounced glacier acceleration. In East Antarctica, the mass balance is near zero, but the thinning of its potentially vulnerable marine sectors suggests this may change in the near future.
Source: University of Bristol
Related stories:
An accurate picture of ice loss in Greenland
Researchers from TU Delft joined forces with the Center for Space Research (CSR) in Austin, Texas, USA, to develop a method for creating an accurate picture of Greenland's shrinking ice cap. On the strength of this method, it is now estimated that Greenland is accountable for a half millimetre-rise in the global sea level per year. These findings will be published in the scientific journal
Geophysical Research Letters in early October.
World's glaciers facing huge threat: UN
The United Nations said Monday that swathes of mountain ranges worldwide risk losing their glaciers by the end of the century if global warming continues at its projected rate.
Moon water discovered: Dampens Moon-formation theory
Using new techniques, scientists have discovered for the first time that tiny beads of volcanic glasses collected from two Apollo missions to the Moon contain water. The researchers found that, contrary to previous thought, water was not entirely vaporized in the violent events that formed the Moon. The new study suggests that the water came from the Moon's interior and was delivered to the surface via volcanic eruptions over 3 billion years ago. The finding calls into question some critical aspects of the "giant impact" theory of the Moon's formation and may have implications for the origin of possible water reservoirs at the Moon's poles. The research is published in the July 10, 2008, issue of
Nature.
Greenland's rising air temperatures drive ice loss at surface and beyond
A new NASA study confirms that the surface temperature of Greenland's massive ice sheet has been rising, stoked by warming air temperatures, and fueling loss of the island's ice at the surface and throughout the mass beneath.
Tipping elements in the Earth's climate system
Anthropogenic forcing could push the Earth’s climate system past critical thresholds, so that important components may “tip” into qualitatively different modes of operation. In the renowned magazine
Proceedings of the National Academy of Sciences (PNAS) an international team of researchers describes, where small changes can have large long-term consequences on human and ecological systems.
Antarctic ice loss speeds up, nearly matches Greenland loss
Ice loss in Antarctica increased by 75 percent in the last 10 years due to a speed-up in the flow of its glaciers and is now nearly as great as that observed in Greenland, according to a new, comprehensive study by UC Irvine and NASA scientists.
New Tibetan Ice Cores Missing A-Bomb Blast Markers; Suggest Himalayan Ice Fields Haven't Grown In Last 50 Years
Ice cores drilled last year from the summit of a Himalayan ice field lack the distinctive radioactive signals that mark virtually every other ice core retrieved worldwide.
Greenland melt accelerating, according to CU-Boulder study
The 2007 melt extent on the Greenland ice sheet broke the 2005 summer melt record by 10 percent, making it the largest ever recorded there since satellite measurements began in 1979, according to a University of Colorado at Boulder climate scientist.
