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[Chicago Astronomer - Astro Joe]

Arctic Ocean could be ice-free in summer within 100 years, scientists say

The current warming trends in the Arctic may shove the Arctic system into a seasonally ice-free state not seen for more than one million years, according to a new report. The melting is accelerating, and a team of researchers were unable to identify any natural processes that might slow the de-icing of the Arctic.

Such substantial additional melting of Arctic glaciers and ice sheets will raise sea level worldwide, flooding the coastal areas where many of the world's people live.

Melting sea ice has already resulted in dramatic impacts for the indigenous people and animals in the Arctic, which includes parts of Alaska, Canada, Russia, Siberia, Scandinavia and Greenland.

"What really makes the Arctic different from the rest of the non-polar world is the permanent ice in the ground, in the ocean and on land," said lead author University of Arizona geoscientist Jonathan T. Overpeck. "We see all of that ice melting already, and we envision that it will melt back much more dramatically in the future as we move towards this more permanent ice-free state."

The report by Overpeck and his colleagues is published in the Aug. 23 Eos, the weekly newspaper of the American Geophysical Union. A complete list of authors and their affiliations is at the end of this release.

In addition to sea and land ice melting, Overpeck warned that permafrost--the permanently frozen layer of soil that underlies much of the Arctic--will melt and eventually disappear in some areas. Such thawing could release additional greenhouse gases stored in the permafrost for thousands of years, which would amplify human-induced climate change.

More here: www.spaceref.com/news/viewpr.html?pid=17679
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On a recent U.S. Senate trip to Alaska, they came back saying that Alaska is melting. I think we are in for some serious times ahead...

[Chicago Astronomer - Astro Joe]

Satellites Detect Significant Ice Loss In Antarctica

Boulder CO (SPX) March 2, 2006
Antarctica's ice sheet has lost a significant amount of ice in just three years, researchers reported Thursday. A team using data from the joint NASA/German Aerospace Center Gravity Recovery and Climate Experiment were able to conduct the first-ever gravity survey of the entire Antarctic ice sheet. Their study found the ice sheet's mass has decreased significantly from 2002 to 2005.
Researchers Isabella Velicogna and John Wahr of the University of Colorado found that the continent at the South Pole has lost a great deal of ice mass since the twin GRACE spacecraft were launched in 2002. The estimated loss was enough to raise global sea level about 1.2 millimeters (0.05 inches) during the survey period, or about 13 percent of the overall observed sea-level rise for the same period.

Reporting in the March 3 issue of the journal Science, the researchers said they found Antarctica's ice sheet decreased by 152 (plus or minus 80) cubic kilometers of ice annually between April 2002 and August 2005.

That is about how much water the United States consumes in three months (a cubic kilometer is 1 trillion liters, or about 264 billion gallons of water). This represents a change of about 0.4 millimeters (.016 inches) per year to global sea-level rise. Most of the mass loss came from the West Antarctic ice sheet.

"Antarctica is Earth's largest reservoir of fresh water," Velicogna said. "The GRACE mission is unique in its ability to measure mass changes directly for entire ice sheets and can determine how Earth's mass distribution changes over time.

Full story here: www.spacedaily.com/reports/Satellites_Detect_Significant_Ice_Loss_In_Antarctica.html

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Well....at least we will see what the ice was covering. I wonder what mysteries we will find?

[Chicago Astronomer - Astro Joe]

Antarctic Ice Sheet Losing Mass

Boulder CO (SPX) Mar 03, 2006
University of Colorado at Boulder researchers have used data from a pair of NASA satellites orbiting Earth in tandem to determine that the Antarctic ice sheet, which harbors 90 percent of Earth's ice, has lost significant mass in recent years.
The team used measurements taken with the Gravity Recovery and Climate Experiment, or GRACE, to conclude the Antarctic ice sheet is losing up to 36 cubic miles of ice, or 152 cubic kilometers, annually. By comparison, the city of Los Angeles uses about 1 cubic mile of fresh water annually.

"This is the first study to indicate the total mass balance of the Antarctic ice sheet is in significant decline," said Isabella Velicogna of CU-Boulder's Cooperative Institute for Research in Environmental Sciences, chief author of the new study that appears in the March 2 online issue of Science Express. The study was co-authored by CU-Boulder physics Professor John Wahr of CIRES, a joint campus institute of CU-Boulder and the National Oceanic and Atmospheric Administration.

The estimated ice mass in Antarctica is equivalent to 0.4 millimeters of global sea rise annually, with a margin of error of 0.2 millimeters, according to the study. There are about 25 millimeters in an inch.

The most recent Intergovernmental Panel on Climate Change assessment, completed in 2001, predicted the Antarctic ice sheet would gain mass in the 21st century due to increased precipitation in a warming climate. But the new study signals a reduction in the continent's total ice mass, with the bulk of loss occurring in the West Antarctic ice sheet, said Velicogna.

As Earth's fifth largest continent, Antarctica is twice as large as Australia and contains 70 percent of Earth's fresh water resources. The ice sheet, which covers about 98 percent of the continent, has an average thickness of about 6,500 feet. Floating ice shelves constitute about 11 percent of the continent.

The melting of the West Antarctic ice sheet alone - which is about eight times smaller in volume than the East Antarctic ice sheet -- would raise global sea levels by more than 20 feet, according to researchers from the British Antarctic Survey.

Full story here: www.terradaily.com/reports/Antarctic_Ice_Sheet_Losing_Mass.html

[Maddad]

Melt both East and West Antarctic ice sheet and sea levels rise what, 180 feet? Think the New Orleans levies will hold?