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Environmental Monitoring


September 2011 Issue

Study Shows How Much Ice Falls Into Sea After Shelves Collapse
An international team of researchers has combined data from multiple sources to provide a clearer account of how much glacial ice surges into the sea following the collapse of Antarctic ice shelves.

The study, published online in the Journal of Glaciology in July, found ice loss in the study area from 2006 to 2010 averaged 10.2 gigatons per year, and ice loss from 2001 to 2006 averaged at least 11.2 gigatons per year.

Previous research showed the recent collapse of several ice shelves in Antarctica led to acceleration of the glaciers that feed into them. By combining satellite data with measurements collected during aircraft missions, researchers produced ice loss maps from 2001 to 2009 for the main tributary glaciers of the Larsen A and B ice shelves, which collapsed in 1995 and 2002, respectively.

"Not only do you get an initial loss of glacial ice when adjacent ice shelves collapse, but you get continued ice losses for many years—even decades—to come," said Christopher Shuman, lead author of the study and a researcher at the Joint Center for Earth Systems Technology. "This further demonstrates how important ice shelves are to Antarctic glaciers."

According to the study, some glaciers had rapid elevation decreases of more than 500 feet. For more information, visit www.sciencedaily.com.

Arctic Sea Ice Extent at Record Low for July
The Arctic sea ice extent average this July reached the lowest level for the month in the 1979 to 2011 satellite record, according to the National Snow and Ice Data Center (NSIDC).

Average ice extent for July 2011 was 7.92 million square kilometers. This is 210,000 square kilometers below the previous record July low set in 2007, and 2.18 million square kilometers below the 1979 to 2000 average for the month. Sea ice coverage remained below normal everywhere except the East Greenland Sea, the NSIDC said.

In the first half of July, Arctic sea ice extent declined at a relatively fast pace due to above-average temperatures and an early start to melt. But ice loss slowed greatly in the latter half of July as weather cooled and likely pushed the ice apart into a thinner but more extensive ice cover, the NSIDC said.

New data show that ice age is now declining in the central Arctic Ocean and the Canadian Arctic Archipelago. A map of ice age for July's third week, combined with sea ice concentration for July 31, shows that in the eastern Beaufort Sea the ice has essentially melted back to the edge of the multiyear ice cover.

In late July, the sea ice edge had retreated from the shores of Siberia and Eurasia, potentially opening up much of the Northern Sea Route. Higher-resolution data indicate that while some ice remains, particularly in the East Siberian Sea, the reduced ice cover in the region has already made the route feasible this year. The Northwest Passage, however, was still choked with ice, the NSIDC said in July. For more information, visit http://nsidc.org.

$4 Million Awarded to Projects Researching MPAs in California
The California Ocean Protection Council awarded $4 million in July to support various projects' initial monitoring of the newly designated marine protected areas (MPAs) along the Southern California coast.

Funded through the South Coast MPA Baseline Program, teams of researchers, citizen-scientists and fishermen will survey the network of new MPAs, collecting baseline information for up to three years, said the California Sea Grant (CSG), which is administering the program. The projects will target marine life and habitats, as well as commercial and recreational activities, inside and outside the MPAs from Point Conception to the California-Mexico border.

Surveys will include ecologically and economically important species of fishes and invertebrates, as well as a range of human activities, such as commercial and recreational fishing, the CSG said. Some teams will study nonconsumptive recreation such as tide-pooling, bird-watching and scuba diving.

Researchers will combine new and historical data to document key aspects of the region's ecological and socioeconomic characteristics at or near the time of MPA implementation, the CSG said. From this, they will be able to document initial changes in marine habitats, species, fisheries and recreation that may be associated with the MPAs.

The results will assist with future assessments of the MPAs' effectiveness in meeting the goals of the Marine Life Protection Act. For more information, visit www.opc.ca.gov.

Coast Guard Studying Arctic in Seven-Month Deployment
The U.S. Coast Guard cutter Healy crew completed its first research mission in the Arctic and is continuing the next three operations of its seven-month-long Arctic West summer and winter deployment, the Coast Guard announced in July.

Working with NASA researchers, the crew collected and studied water and ice samples to examine the refractive properties of sunlight in the Arctic. Healy then stopped in Seward, Alaska, in July for a week of rest and maintenance before beginning its remaining three missions in the Beaufort Sea and Arctic Ocean.

In August, Healy's crew was collaborating with the Canadian Coast Guard icebreaker Louis S. St. Laurent to map the floor of the Arctic Ocean. The third operation will deploy several types of hydrographic moorings and recover moorings deployed on earlier missions. The final operation will study copepod behavior in the winter. For more information, visit www.uscg.mil.

University of Texas Opens Estuarine Research Center
The University of Texas Marine Science Institute opened its Estuarine Research Center at Port Aransas in July.

The three-floor building has state-of-the-art marine laboratories and is also the headquarters of the Mission-Aransas National Estuarine Research Reserve, an 185,708-acre area of estuarine habitat established by NOAA and managed by the institute.

The center was built as a partnership among the university, NOAA and the Texas General Land Office. For more information, visit www.utmsi.utexas.edu.


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