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U.S. explores Arctic Ocean sovereignty Five-year team-up with Canada concludes as scientists aboard icebreakers collect huge amounts of seismic and other data in polar sea Wesley Loy For Petroleum News
As global climate change opens the possibility for greater industrial involvement in the Arctic Ocean, the United States is seeking to establish the full reach of its claims at the top of the world.
And it’s making significant progress.
U.S. officials say a summer 2011 mission with Canada wrapped up a five-year collaboration between the two nations to survey the Arctic Ocean.
“The bilateral project collected scientific data to delineate the continental shelf beyond 200 nautical miles from the coastline, also known as the extended continental shelf,” said a Dec. 15 press release from the National Oceanic and Atmospheric Administration.
At the center of the collaboration was a pair of ice-breaking ships — the U.S. Coast Guard cutter Healy, and the Canadian Coast Guard ship Louis S. St-Laurent.
Cost-effective partnership The United States “has an inherent interest in knowing, and declaring to others, the exact extent of its sovereign rights in the ocean as set forth in the Convention on the Law of the Sea,” NOAA said.
For the extended continental shelf, the interest is in energy resources such as oil, natural gas and gas hydrates; marine stocks such as crabs and clams; and mineral resources such as manganese nodules, ferromanganese crusts and polymetallic sulfides, the agency said.
The U.S. and Canadian icebreakers worked together in August and September on an Arctic mission that lasted nearly six weeks.
“This two-ship approach was both productive and necessary in the Arctic’s difficult and varying ice conditions,” said Larry Mayer, U.S. chief scientist on the mission. “With one ship breaking ice for the other, the partnership increased the data either nation could have obtained operating alone, saved millions of dollars by ensuring data were collected only once, provided data useful to both nations for defining the extended continental shelf, and increased scientific and diplomatic cooperation.”
How big is it? The extended continental shelf is that region beyond the U.S. Exclusive Economic Zone, which reaches to 200 nautical miles offshore.
The U.S. extended shelf is not limited to the Arctic. It might include areas in the Bering Sea, the Gulf of Alaska, the Atlantic Ocean and the Gulf of Mexico, as well as in the Pacific Ocean off northern California, northwest of Hawaii and near the Mariana and Line islands.
Preliminary studies indicate the U.S. extended continental shelf totals an area about twice the size of California, NOAA said. Additional data collection and analysis is expected to sharpen the estimate.
Another agency, the U.S. Geological Survey, in 2011 collected seismic data in the Bering Sea and Gulf of Alaska as part of efforts to delineate the extended continental shelf.
Many miles traversed The 2011 Arctic mission was led by the Joint Hydrographic Center, which is a partnership between NOAA and the University of New Hampshire, and the Geological Survey of Canada.
On the U.S. icebreaker Healy, scientists used a multibeam echo sounder to collect bathymetric data to create three-dimensional images of the seafloor.
Scientists aboard the Canadian icebreaker Louis S. St-Laurent collected seismic data to determine the thickness of the sediments beneath the seafloor — an important step under the rules for defining the extended shelf — and to better understand the geology of the Arctic Ocean.
The 2011 mission traversed more than 5,600 total miles over the Beaufort Shelf, Chukchi Borderland, Alpha Ridge and Canada Basin and reached more than 1,230 miles north of the Alaska coast, NOAA said.
“As in previous Arctic missions, we obtained data in areas we were not entirely sure the ice would allow us to proceed, even with a two-ship operation,” said Andy Armstrong, co-chief scientist on the mission and co-director of the Joint Hydrographic Center. “This was especially true in the eastern part of the Canada Basin where some of the thickest Arctic ice is found.”
Reams of seismic data From 2006 to date, scientists onboard the Louis S. St-Laurent have collected 9,320 miles of seismic data, vastly increasing the seismic data holdings in the deep Arctic Ocean.
“Scientists from the United States and Canada are using these seismic data to revise models of the origin and tectonic evolution of this poorly understood portion of the ocean,” NOAA said.
Since the 2003 start of U.S. extended continental shelf work in the Arctic, the Healy alone has mapped some 123,000 square miles of the Arctic seafloor, an area about the size of Arizona.
“These data provided high resolution maps to help determine the outer limits of the U.S. extended continental shelf, while revealing previously undiscovered mountains, known as seamounts, and scours created by past glaciers and icebergs scraping along the ocean bottom 400 meters below the surface,” Mayer said.
The U.S. Extended Continental Shelf Task Force is responsible for the delineation effort. The Department of State chairs the interagency body, with the Interior Department and NOAA serving as vice chairs.
More information is available at www.continentalshelf.gov.
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