Featured Research

from universities, journals, and other organizations

Continental Slope Off Alaska 100 Nautical Miles Further Off Coast Than Assumed

Date:
February 12, 2008
Source:
University of New Hampshire
Summary:
New Arctic sea floor data suggests that the foot of the continental slope off Alaska is more than 100 nautical miles farther from the US coast than previously assumed. The data, gathered during a recent mapping expedition north of Alaska, could support US rights to natural resources of the sea floor beyond 200 nautical miles from the coast.

International Bathymetric Chart of the Arctic Ocean. Chukchi Borderland is between 160W and 170W degrees longitude and 75N and 80N degrees latitude.
Credit: UNH/NOAA

New Arctic sea floor data just released by the University of New Hampshire and the National Oceanic and Atmospheric Administration suggests that the foot of the continental slope off Alaska is more than 100 nautical miles farther from the U.S. coast than previously assumed. The data, gathered during a recent mapping expedition to the Chukchi Cap some 600 nautical miles north of Alaska, could support U.S. rights to natural resources of the sea floor beyond 200 nautical miles* from the coast.

Related Articles


"We found evidence that the foot of the slope was much farther out than we thought," said Larry Mayer, expedition chief scientist and co-director of the Joint Hydrographic Center at UNH. "That was the big discovery."

Coastal nations have sovereign rights over the natural resources of their continental shelf, generally recognized to extend 200 nautical miles out from the coast. The Law of the Sea Convention, now under consideration in the U.S. Senate, provides nations an internationally recognized basis to extend their sea floor resource rights beyond the foot of the continental slope if they meet certain geological criteria backed up by scientific data.

The Bush administration supports approval of the convention. The Arctic mapping expedition, conducted between Aug. 17 and Sept. 15, 2007 aboard the U.S. Coast Guard Cutter Healy, employed sophisticated echo sounders to survey this relatively unexplored region, providing much finer-grained data and images than existed previously.

"We now have a better geologic picture of what's happening in that area of the Arctic," said NOAA Office of Coast Survey researcher Andy Armstrong, co-chief scientist on the expedition and NOAA co-director of the Joint Hydrographic Center. "These are valuable data for NOAA and the United States, and I'm pleased that we're making them available for anyone to use."

Mapping more than 5,400 linear nautical miles, the research team also found scours on the Chukchi Cap some 1,300 feet below the surface, likely caused by the scraping of an ice sheet on the sea floor, and deep pockmarks of unknown origin at a depth of 1,600 feet.

"The sea floor is full of mysteries, and beneath the Arctic ice cap those mysteries are even harder to reveal," said Mayer. "The kind of full-coverage, high-resolution mapping we do provides critical insight for meeting the criteria of the Law of the Sea Convention as well as the geologic history of the region."

Prior to this work, the only seafloor mapping data available in the ice-covered Arctic came mostly from ice islands and helicopters. These sparse individual measurements produced low-resolution maps compared to the Joint Hydrographic Center's mapping.

Other mapping expeditions led by the Joint Hydrographic Center, a NOAA-UNH partnership, have explored the Bering Sea (2003), the Atlantic coast of the U.S. (2004 and 2005), the Gulf of Alaska (2005), Mariana Islands (2006 and 2007), and the Gulf of Mexico (2007).

"Understanding the bathymetry and geological history of the Arctic is an important part of understanding global climate change," said Mayer. "The Arctic acts as a global spigot in controlling the flow of deep ocean currents that distribute the Earth's heat and control climate. The Arctic is the canary in the coal mine."

* One nautical miles equals 1.15 statute miles or 1852 meters.


Story Source:

The above story is based on materials provided by University of New Hampshire. Note: Materials may be edited for content and length.


Cite This Page:

University of New Hampshire. "Continental Slope Off Alaska 100 Nautical Miles Further Off Coast Than Assumed." ScienceDaily. ScienceDaily, 12 February 2008. <www.sciencedaily.com/releases/2008/02/080211134449.htm>.
University of New Hampshire. (2008, February 12). Continental Slope Off Alaska 100 Nautical Miles Further Off Coast Than Assumed. ScienceDaily. Retrieved March 29, 2015 from www.sciencedaily.com/releases/2008/02/080211134449.htm
University of New Hampshire. "Continental Slope Off Alaska 100 Nautical Miles Further Off Coast Than Assumed." ScienceDaily. www.sciencedaily.com/releases/2008/02/080211134449.htm (accessed March 29, 2015).

Share This


More From ScienceDaily



More Earth & Climate News

Sunday, March 29, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Antarctic Ice Is Melting Faster Than Ever

Antarctic Ice Is Melting Faster Than Ever

Newsy (Mar. 27, 2015) A new study of nearly two decades of satellite data shows Antarctic ice shelves are losing more mass faster every year. Video provided by Newsy
Powered by NewsLook.com
Raw: Homes Near Landslide in Washington

Raw: Homes Near Landslide in Washington

AP (Mar. 27, 2015) Aerial footage from KOMO shows several homes near a landslide in Washington. KOMO reports that at least one of the homes has been damaged. (March 27) Video provided by AP
Powered by NewsLook.com
Clean-Up Follows Deadly Weather in Okla.

Clean-Up Follows Deadly Weather in Okla.

AP (Mar. 26, 2015) Gov. Mary Fallin has declared a state of emergency for 25 Oklahoma counties after powerful storms rumbled across the state causing one death, numerous injuries and widespread damage. (March 26) Video provided by AP
Powered by NewsLook.com
At Least Four Dead After Floods in Northern Chile

At Least Four Dead After Floods in Northern Chile

Reuters - News Video Online (Mar. 26, 2015) At least four people have been killed by severe flooding in northern Chile after rains battered the Andes mountains and swept into communities below. Rob Muir reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins