August 10, 2009
U.S. Coast Guard icebreaker Healy and the Canadian Coast Guard icebreaker Louis S. St-Laurent side by side.
High resolution (Credit: USGS)
NOAA will join a multi-agency joint expedition that will bring together icebreakers from the U.S. and Canada to collect and share data useful to both countries in defining the full extent of the Arctic continental shelf.
The Arctic survey is part of the multi-year, multi-agency effort undertaken by the U.S. Extended Continental Shelf Project, led by the Department of State, with vice co-chairs from the Department of the Interior and NOAA. NOAA’s Office of Ocean Exploration and Research provided key funding for the U.S. mission. This year, the survey will include a NOAA Teacher at Sea.
Under international law, every coastal nation is entitled to delineate the outer limit of its continental shelf beyond 200 nautical miles from shore. Within this extended continental shelf, the coastal state has sovereign rights over the natural resources.
Larry Mayer, director of the Center for Coastal and Ocean Mapping and co-director of the Joint Hydrographic Center, is the chief scientist for the U.S. mission. NOAA’s Andy Armstrong, a physical scientist and co-director of the Joint Hydrographic Center, is the co-chief scientist. NOAA and the University of New Hampshire jointly operate the Joint Hydrographic Center.
The Healy crew lowers equipment into the ocean.
High resolution (Credit: NOAA)
The 41-day joint mission runs from August 7 to September 16 and will see the U.S. Coast Guard Cutter Healy and the Canadian Coast Guard Ship Louis S. St-Laurent operating together to obtain a variety of data.
“NOAA and the Joint Hydrographic Center will take the lead in collecting bathymetric data from the Healy to map the seafloor, while the Canadian icebreaker collects seismic data to determine sediment thickness,” said Craig McLean, deputy assistant administrator for NOAA’s Office of Oceanic and Atmospheric Research. “This collaboration saves millions of dollars by ensuring data are collected only once in the same area, and by sharing data useful to both nations.”
Christine Hedge, a school teacher from Carmel Middle School in Carmel, Ind., has been selected to be a NOAA Teacher at Sea to serve on board the Healy during the mapping. Sponsored by NOAA’s National Marine Fisheries Service and NOAA’s Office of Marine and Aviation Operations, NOAA Teachers at Sea have the opportunity to interact with scientists on vessels and develop lesson plans and activities to bring back to the classroom. On this mission, Hedge will learn more about hydrography, as well as ecosystems and resources within the North American extended continental shelf.
An aerial view of the Chukchi Borderland from the north, with tracks from 2003, 2004 and 2007 mapping expeditions.
High resolution (Credit: UNH/NOAA)
Deborah Hutchinson, a scientist from the U.S. Geological Survey, will ride the Canadian icebreaker to coordinate seismic data collection with counterparts from the Geological Survey of Canada, a part of the Earth Sciences Sector of Natural Resources Canada. A Canadian scientist will ride the Healy.
The 2009 mission continues the U.S.-Canada partnership begun last year, and plans are in place to continue joint operations in 2010. The mission builds on earlier Arctic mapping efforts funded by NOAA. Data collected this year will emphasize the region of the central to northern Chukchi Borderland – the large undersea plateau that extends into the Arctic Basin north of Alaska – northwards onto Alpha-Mendeleev Ridge and eastwards toward the Canadian Arctic Archipelago. Final locations will depend on ice conditions. When one ship is focused on collecting data, the other ship will sail ahead to break ice for a clear and open path.
A country may use either constraint line to define the outer limits of its continental shelf: either 350 nautical miles seaward of the baseline, or 100 nautical miles seaward of the 2,500-meter depth contour (isobath).
High resolution (Credit: continentalshelf.gov)
“The mission’s primary purpose is to determine the full extent of the continental shelf, but the data collected during this cruise will also help us learn more about seafloor processes, ocean circulation, the geologic origin of the Arctic basin, ecosystems, and navigation,” said Armstrong.
Previous mapping missions have revealed bathymetric “pockmarks” on the Chukchi Borderland thought to be gas seeps. These could host chemosynthetic ecosystems where ocean life is based on energy from chemicals rather than from the sun. In addition, the discovery of an unmapped seamount, since named Healy Seamount, will enable safer submarine navigation.
On this year’s mission, NOAA’s Pablo Clemente-Colón, chief scientist at the U.S. National Ice Center, will coordinate the deployment of buoys to monitor ice, atmospheric and upper ocean thermal conditions in the Arctic Ocean as part of the International Arctic Buoy Program and the Arctic Observing Network efforts.
Members of the U.S. Extended Continental Shelf Task Force are the U.S. Department of State, National Oceanic and Atmospheric Administration, Department of the Interior, Executive Office of the President, U.S. Geological Survey, U.S. Coast Guard, National Science Foundation, Joint Chiefs of Staff, U.S. Navy, Department of Energy, Environmental Protection Agency, Minerals Management Service, and the Arctic Research Commission.NOAA understands and predicts changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.