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The BEAUFORT SEA (French : mer de Beaufort) is a marginal sea of the Arctic Ocean
Arctic Ocean
, located north of the Northwest Territories
Northwest Territories
, the Yukon , and Alaska
Alaska
, west of Canada\'s Arctic islands . The sea is named after hydrographer Sir Francis Beaufort
Francis Beaufort
. The major Mackenzie River empties into the Canadian part of the sea, west of Tuktoyaktuk , which is one of the few permanent settlements on the sea shores.

The sea, characterized by severe climate, is frozen over most of the year. Historically, only a narrow pass up to 100 km (62 mi) opened in August–September near its shores, but recently due to climate change in the Arctic the ice-free area in late summer has greatly enlarged. Claims that the seacoast was populated about 30,000 years ago have been largely discredited (see below); present population density is very low. The sea contains significant resources of petroleum and natural gas under its shelf, such as the Amauligak field. They were discovered in the period between the 1950s and 1980s, and their exploration became the major human activity in the area since the 1980s. The traditional occupations of fishery and whale and seal hunting are practiced only locally, and have no commercial significance. As a result, the sea hosts one of the largest colonies of beluga whales , and there is no sign of overfishing . To prevent overfishing in its waters, the US adopted precautionary commercial fisheries management plan in August 2009. In April 2011 the Canadian government signed a memorandum of understanding with the Inuvialuit as a first step in developing a larger ocean management plan. The Canadian government announced in October 2014 that no new commercial fisheries in the Beaufort Sea
Sea
will be considered until research has shown sustainable stocks that would be made available to Inuvialuit first.

The Canadian government has set a new block of the Beaufort Sea
Sea
off the Parry Peninsula in the Amundsen as a Marine Protected Area (MPA). The protected area is set to protect species and habits for the Inuvialuit community.

CONTENTS

* 1 Extent * 2 Border dispute * 3 Geography * 4 Hydrology and climate * 5 Flora and fauna * 6 Human activities * 7 Oil and Gas Exploration * 8 In popular culture * 9 See also * 10 References * 11 Bibliography * 12 Further reading * 13 External links

EXTENT

The International Hydrographic Organization
International Hydrographic Organization
defines the limits of the Beaufort Sea
Sea
as follows:

On the North. A line from Point Barrow , Alaska, to Lands End, Prince Patrick Island (76°16′N 124°08′W / 76.267°N 124.133°W / 76.267; -124.133 ).

On the East. From Lands End through the Southwest coast of Prince Patrick Island to Griffiths Point, thence a line to Cape Prince Alfred, the Northwestern extreme of Banks Island
Banks Island
, through its West coast to Cape Kellet, the Southwestern point, and thence a line to Cape Bathurst on the mainland (70°36′N 127°32′W / 70.600°N 127.533°W / 70.600; -127.533 ).

BORDER DISPUTE

The cross-hatched wedge-shaped region in the east is claimed by both Canada
Canada
and the US See also: Territorial claims in the Arctic § Beaufort Sea
Sea

There is an unresolved dispute involving a wedge-shaped slice on the International Boundary in the Beaufort Sea, between the Canadian territory of Yukon
Yukon
and the U.S. state of Alaska. Canada
Canada
claims the maritime boundary to be along the 141st meridian west out to a distance of 200 nmi (370 km; 230 mi), following the Alaska–Yukon land border. The position of the United States is that the boundary line is perpendicular to the coast out to a distance of 200 nmi (370 km; 230 mi), following a line of equidistance from the coast. This difference creates a wedge with an area of about 21,000 km2 (8,100 sq mi) that is claimed by both nations.

Canada's position has its roots in the Treaty of Saint Petersburg (1825) between the United Kingdom and the Russian Empire
Russian Empire
that set the boundary between the two. Canada
Canada
is the successor state to Great Britain in relation to this treaty, which stipulates:

the line of demarcation shall follow the summit of the mountains situated parallel to the Coast, as far as the point of intersection of the 141st degree of West longitude and, finally, from the said point of intersection, the said Meridian Line of the 141st degree, in its prolongation as far as the Frozen Ocean
Ocean
— Article 3, Convention between Great Britain and Russia concerning the Limits of their Respective Possessions on the North-West Coast of America and the Navigation of the Pacific Ocean, 1825-02-16, 75 CTS 95

Canada
Canada
maintains that this treaty is extensible from the land into the Beaufort Sea
Sea
along the meridian. The United States rejects this extension and instead asserts a boundary line based upon equidistance, although its position is somewhat undermined by its acceptance in 1867 of similar treaty wording and a similar interpretation under the treaty whereby it acquired Alaska
Alaska
. Both the U.S. and Canada
Canada
agree that they are bound by the 1958 Convention on the Continental Shelf ; and they both agree that the boundary should be "equitable", as determined by the International Court of Justice
International Court of Justice
. They differ on what should be deemed "equitable". The U.S. contends that "equidistance is an appropriate principle for determining a maritime boundary where there are no special circumstances in the area and when equidistance results in a boundary in accordance with equitable principles". Canada contends that an equidistance principle does not result in an equitable boundary, because distortion would occur. The coast of Yukon is concave, whereas the coast of Alaska
Alaska
is convex; and thus an equidistance principle would result in a significant extension of the U.S. possession. This dispute has taken on increased significance due to the possible presence of natural reserves within the wedge, which according to Canada's National Energy Board may contain 1,700,000,000 m3 (6.0×1010 cu ft) of gas, which would cover the national consumption for 20 years, and more than 1,000,000,000 m3 (3.5×1010 cu ft) of oil. Because of this, Canada
Canada
argues that "special circumstances" apply to this border, a position that the U.S. rejects. This dispute is in this respect a mirror image of the dispute between the U.S. and Canada
Canada
over the Gulf of Maine
Gulf of Maine
, where the U.S. argued for "special circumstances" and Canada
Canada
argued for the equidistance principle. (It is to be noted that in that latter dispute, both of those arguments were rejected, and the border was drawn based upon geometric principles taking into account geographic factors. ) Neither the U.S. nor Canada
Canada
have pressed for a swift resolution for the matter, or arbitration at the International Court of Justice, however; and the two have in the meantime cooperated in several measures aimed at preserving the maritime environment.

Before the end of 2004, the US leased eight plots of land below the water for oil exploration and exploitation, provoking a diplomatic protest from Canada. On 20 August 2009, United States Secretary of Commerce Gary Locke
Gary Locke
announced a moratorium on commercial fishing of the Beaufort Sea
Sea
north of Alaska, including the disputed waters. In July 2010, US– Canada
Canada
negotiations have started in Ottawa with the next meeting planned in 2011. A joint geological survey of the area has been initiated, and the issue was marked as settled by the CIA World Factbook , though no official document has been released by September 2010.

GEOGRAPHY

Topography of the Beaufort Sea
Sea
area.

Several rivers such as the Kongakut River in Alaska
Alaska
and the Firth River in Yukon
Yukon
empty into the Beaufort. The major river to flow into the sea is the Mackenzie, Canada's longest, which empties into the Canadian part of the sea, west of Tuktoyaktuk. The coastal shelf area is rather narrow, especially near and east of Point Barrow in the Alaskan part of the sea, and contains numerous submarine valleys . It becomes wider near the delta of the Mackenzie River
Mackenzie River
but nowhere exceeds 145 km (90 mi). Near the coast, the depths are shallower than 60 m (200 ft) but they rapidly increase northwards up to a few kilometers, transforming into a massive platform which is geologically similar to that of the oceans. There are many small islands in the sea and in the delta of the Mackenzie River. A few larger ones lie west of the Mackenzie River, such as Herschel Island (4 km (2.5 mi) off the shore, area 18 km2 (6.9 sq mi)) and Barter Island (0.3 km (0.19 mi) from the coast, area 13 km2 (5.0 sq mi)). The coasts are low, with the maximum elevations between 250 and 750 m (820 and 2,460 ft). The soil is frozen all year around at the depth below about 1 m (3 ft 3 in) or less, forming permafrost , and only top few tens centimeters thaws in summer. Consequently, buildings have to be elevated above ground on wooden piles that are immersed into the permafrost.

HYDROLOGY AND CLIMATE

Sea
Sea
ice pressure ridges in the Beaufort Sea
Sea
off the northern coast of Alaska
Alaska
(spring 1949).

The Beaufort Sea
Sea
is frozen over through the year, except for August and September when the ice breaks near the coast and opens what was once a 50–100 km (31–62 mi) wide strip of open water. During the 2000s, due to climate change in the Arctic , the ice-free area in late summer greatly enlarged. During the record minimum extent of Arctic sea ice in September, 2012, the sea ice boundary had retreated northward much farther than normal from the coast.

The channels of the Mackenzie River
Mackenzie River
thaw earlier, in late May–early June. This thawing increases the average water discharge from about 150,000 to 250,000 m3/s (5,300,000 to 8,800,000 cu ft/s).

Hidden changes in the ice cover of the Beaufort Sea
Sea
were discovered in 2009. Whereas the ice area remain stable, as detected by the observation satellites, so as the associated water temperature and salinity , the ice structure has changed recently. The new ice, called rotten ice , is thinner and much weaker structurally.

The sea water has a stable temperature and is separated into four distinct layers as follows. The top 100 m (330 ft) are surface water which has a temperature of −1.4 °C (29.5 °F) in summer and −1.8 °C (28.8 °F) in winter. The next layer is formed by the inflows from the Pacific Ocean
Pacific Ocean
and Bering Sea
Sea
coming through the Bering Strait
Bering Strait
; it extends up to the North Pole
North Pole
. The warmest, deep Atlantic layer has the temperatures between 0 and 1 °C (32 to 34 °F), and water at the bottom is a bit colder at −0.4 to −0.8 °C (31.3 to 30.6 °F). The average salinity varies between 28‰ and 32‰ (parts per thousand) from south to north. Typical air temperatures (at Tuktoyaktuk) are −27 °C (−17 °F) in January and 11 °C (52 °F) in July. Northstar Island , an artificial island northwest of Prudhoe Bay, is a site of oil and gas drilling

The water currents form the clockwise-directed Beaufort Gyre , that results in south-westerly and westerly currents near the shores. The Mackenzie River
Mackenzie River
partly affects this circulation inducing minor eastwards streams near its mouth. The river annually brings about 15 million tonnes of sediments which are rich in dolomite and calcium carbonate . Those deposits are spread over the sea and mixed with mud and gravel.

FLORA AND FAUNA

The shoreline of the Beaufort Sea
Sea
is covered with tundra and the northern limit of the terrestrial range of the polar bear in North America . The Mackenzie River
Mackenzie River
is an important habitat for whales and seabirds and is still relatively untouched by commercial traffic. The delta of Mackenzie River
Mackenzie River
contains numerous lakes and ponds which are inhabited by muskrat .

The sea hosts about 80 species of zooplankton , more than 70 species of phytoplankton , and nearly 700 species of polychaetes , bryozoans , crustaceans and mollusks , but their total volume is relatively small owing to the cold climate. Major fish species include polar cod (Boreogadus saida), Arctic cod (Arctogadus glacialis), saffron cod (Eleginus gracilis), Arctic char
Arctic char
(Salvelinus alpinus), chum salmon (Oncorhynchus keta), Arctic cisco (Coregonus autumnalis), least cisco (Coregonus sardinella), lake whitefish (Coregonus clupeaformis), broad whitefish (Coregonus nasus), Pacific herring (Clupea pallasii), fourhorn sculpin (Myoxocephalus quadricornis), inconnu (Stenodus leucichthys) and flatfish . Endicott Island

The eastern part of the sea is a major habitat of beluga whales with an estimated population of 39,000. This population is stable and might even be increasing; it is not affected by the offshore oil exploration in the area. Belugas spend summer in the coastal area and Mackenzie River delta, which are free of ice then, and in winter migrate log distances to the polynyas of the deep sea. Genetic analyses have confirmed that belugas of the Beaufort Sea
Sea
are clearly distinct from those of other Canadian and Alaskan waters, despite they often share a common wintering habitat.

The food chain of the Beaufort Sea
Sea
is relatively simple: It starts with phytoplankton and epontic algae (single-cell algae associated with the lower interface of sea ice ), which provide energy to zooplankton, and epontic and coastal amphipods. The latter serve as a food for seabirds and fish, primarily as polar cod and Arctic char. Polar cod is a major food of Arctic char, beluga, narwhal , seabirds and seals, which are dominated by the bearded seal (Erignatus barbatus) and ringed seal (Pusa hispida). Bearded seal and walrus also feed on benthic invertebrates. On top of the food pyramid stands polar bear, which feeds primarily on seals, but also on any large marine mammals when it has a chance, such as carcasses and whales trapped in ice fields.

HUMAN ACTIVITIES

A map showing the Trans- Alaska
Alaska
Pipeline colored in red.

"There is only one proposed Early-Entry site in eastern Beringia that still has proponents, Bluefish Caves in the Porcupine River Basin, Yukon
Yukon
Territory, Canada. Claims of great antiquity in the area have a convoluted history. A caribou tibia flesher, the most diagnostic human implement from the Old Crow basin, had been dated at near 28 kya. When redated using accelerator mass spectrometry (AMS) of small amounts of remnant collagen the bone produced a 1.8 kya date (Yesner 1996b:255)". There is no evidence for anomalous occupation of Beaufort coasts in the context of Arctic cultures generally, including the arrival about 4,000 years ago by Paleo-Eskimos such as the Dorset culture
Dorset culture
, around 1,000 years ago by the Thule and finally by the modern Inuit
Inuit
. From early ages, they practised fishing – bones of Arctic char
Arctic char
were found at the 4,000 years old settlements. While originally they lived nomadic life, later, they started to form permanent settlements. Modern Inuit
Inuit
are mostly concentrated near the Mackenzie River
Mackenzie River
delta. Their population is increasing, but the unemployment rate is relatively high.

Bowhead whales were hunted in the sea between 1888 and 1914. This practice stopped, first because of the decline in whale population and then because of government regulations, but resumed in the 1990s.

The major settlements along the Beaufort Sea
Sea
are Tuktoyaktuk (population 930 in 2009 ) in Canada
Canada
and Prudhoe Bay, Alaska
Alaska
. Although Prudhoe Bay is permanently populated by only a few people, there are thousands of contract workers in the area employed on petroleum production at the Prudhoe Bay Oil Field
Prudhoe Bay Oil Field
, which is on the coastal lowland known as the North Slope . Artificial islands , such as Endicott and Northstar , have been raised near the shores in 1987 and 2001, respectively. The crude oil is transported through the Trans- Alaska
Alaska
Pipeline System to the southern port of Valdez .

Fishing and sea hunting are practised by the local inhabitants and have no commercial value, especially after a US moratorium on commercial fishing of the Beaufort Sea, adopted in 2009. Trapping of muskrat at the Mackenzie River
Mackenzie River
delta was the main source of income for the Athabaskan First Nations peoples and Inuit
Inuit
during 1920–1960, but has since declined.

OIL AND GAS EXPLORATION

The Beaufort Sea
Sea
contains major gas and petroleum reserves beneath the seabed, a continuation of proven reserves in the nearby Mackenzie River and North Slope. The Beaufort Sea
Sea
was first explored for sub-shelf hydrocarbons in the 1950s and estimated to contain about 250 km3 (60 cu mi) of oil and 300,000 km3 (72,000 cu mi) of natural gas under its coastal shelf. Offshore drilling began in 1972; about 70 wells were set up by the 1980s and 200 wells by 2000. These activities resulted in dredging of about 46.5 million m3 of sea bottom soil, as well as discharge of drilling muds which contained barite , clay, caustic soda , and heavy metals zinc, copper, lead, chromium, cobalt, nickel, cadmium and mercury. About 50,400 m3 (1,780,000 cu ft) of oil was produced in 1986.

A major gas field, named TAGLU GAS FIELD, was discovered in the Mackenzie River
Mackenzie River
delta in 1971, followed by the Parson Lake field and Niglintgak field. The estimated gas reserves of these fields are 58,600 km3 (14,100 cu mi), 35,400 km3 (8,500 cu mi) and 13,600 km3 (3,300 cu mi), respectively. Moreover, further into the sea from the Mackenzie delta lies the Amauligak field. This, the largest known oil deposit of the Beaufort Sea, was discovered in 1984, and is estimated to contain 37.3 km3 (8.9 cu mi) of oil and 38,500 km3 (9,200 cu mi) of gas. The development of these fields is hindered by their remote location. This problem was alleviated for Prudhoe Bay by constructing the Trans- Alaska
Alaska
Pipeline, but is limiting regular commercial production at Mackenzie River
Mackenzie River
deposits. For example, the AMAULIGAK PROJECT was started soon after the discovery of the field. In September 1985, the tanker Gulf Beaufort has transported 50,300,000 l (316,377 bbl) of crude oil to Japan, which was the first shipment of oil from the Arctic deposits. However, the project has stalled after that.

IN POPULAR CULTURE

Stan Rogers references the Beaufort Sea
Sea
in his popular Canadian Folk Song Northwest Passage (song) .

SEE ALSO

* Arctic portal

* Arctic policy of the United States * Canadian Internal Waters * List of areas disputed by Canada
Canada
and the United States * List of seas * Northwest Passage
Northwest Passage
* Petroleum exploration in the Arctic

REFERENCES

* ^ R. Stein, Arctic Ocean
Arctic Ocean
Sediments: Processes, Proxies, and Paleoenvironment, p. 37 * ^ A B C Beaufort Sea, Great Soviet Encyclopedia
Great Soviet Encyclopedia
(in Russian) * ^ A B C D E F G Beaufort Sea, Encyclopædia Britannica on-line * ^ John Wright (30 November 2001). The New York Times Almanac 2002. Psychology Press. p. 459. ISBN 978-1-57958-348-4 . Retrieved 29 November 2010. * ^ Arctic Fishery Management Plan. * ^ Beaufort Sea
Sea
Commercial Fishing Banned (CBC News 15 April 2011). * ^ No new fisheries in the Arctic following federal ban * ^ " Canada
Canada
Designates Its Second And Largest Arctic Marine Protected Area". * ^ "Limits of Oceans and Seas, 3rd edition" (PDF). International Hydrographic Organization. 1953. Retrieved 6 February 2010. * ^ The Law of the Sea
Sea
Convention (BP-322E) Archived 28 February 2007 at the Wayback Machine
Wayback Machine
.. Dsp-psd.communication.gc.ca. Retrieved on 2013-03-21. * ^ A B C D E F G H Donald Rothwell (1996). The Polar Regions and the Development of International Law. Cambridge studies in international and comparative law. 3. Cambridge University Press. pp. 174, 176. ISBN 978-0-521-56182-2 . * ^ Summary of claims, Department of Defense, p. 10 * ^ A B US- Canada
Canada
Arctic border dispute key to maritime riches, BBC News, 2 August 2010 * ^ A B C D E Douglas M. Johnston & Phillip M. Saunders (1988). Ocean
Ocean
Boundary Making: Regional Issues and Developments. Taylor & Francis. pp. 48–49. ISBN 978-0-7099-1495-2 . * ^ Northern interests and Canadian foreign policy Archived 16 August 2010 at the Wayback Machine
Wayback Machine
., Associate Director Centre for Military and Strategic Studies, University of Calgary * ^ Beaufort Sea
Sea
Areawide 2006, Tract Map No.8, State of Alaska Department of Natural Resources, Division of oil and gas * ^ A B Sea
Sea
Changes, Institute of the North * ^ "Secretary of Commerce approves fisheries plan for ArcticSecretary of Commerce approves fisheries plan for Arctic". World of fishing. 20 August 2009. Archived from the original on 15 September 2009. * ^ Randy Boswell (4 September 2009). " Canada
Canada
protests U.S. Arctic fishing ban". Canada.com . Archived from the original on 15 September 2009. * ^ Disputes – international: CIA – The World Factbook. Cia.gov. Retrieved on 2013-03-21. * ^ A B C D Mackenzie River, Encyclopædia Britannica on-line * ^ "Poles apart: A record-breaking summer and winter". National Snow and Ice Data Center . 2 October 2012. Archived from the original on 4 February 2013. Arctic sea ice extent averaged for September 2012 was 3.61 million square kilometers (1.39 million square miles). This was 3.43 million square kilometers (1.32 million square miles) below the 1979 to 2000 average extent. September 2012 ice extent was 690,000 square kilometers (266,000 square miles) less than the previous record low for the month that occurred in 2007. * ^ Anderson, Ben (23 September 2012). "Rotting whale meat lures record 80 polar bears to Kaktovik". Alaska
Alaska
Dispatch. Archived from the original on 4 February 2013. While the whale carcass is one reason for the polar bear bonanza, scientists wonder if there isn’t another reason. Namely, the record retreat of Arctic sea ice from the northeast coast of Alaska
Alaska
into the Beaufort Sea. * ^ Jay, By Chadwick V.; Fischbach, Anthony S. (9 January 2013). "Pacific Walrus
Walrus
Response to Arctic Sea
Sea
Ice Losses". United States Geological Survey. Archived from the original on 4 February 2013. The extent of Arctic summer sea ice has decreased sharply over the past several decades (Stroeve and others, 2007). * ^ "Arctic Sea
Sea
Ice Hits Smallest Extent In Satellite Era". National Aeronautics and Space Administration. 19 September 2012. Archived from the original on 4 February 2013. The new record minimum measures almost 300,000 square miles less than the previous lowest extent in the satellite record, set in mid-September 2007, of 1.61 million square miles (4.17 million square kilometers). For comparison, the state of Texas measures around 268,600 square miles. * ^ Ice Is \'Rotten\' in the Beaufort Sea, ScienceDaily, 23 January 2010 * ^ Canadian Climate Normals 1971–2000. climate.weatheroffice.gc.ca * ^ Parsons, pp. 213–214 * ^ C. Michael Hogan (2008) Polar Bear: Ursus maritimus, Globaltwitcher.com, ed. N. Stromberg Archived 24 December 2008 at the Wayback Machine
Wayback Machine
. * ^ Parsons, pp. 214–215 * ^ Parsons, pp. 218, 221 * ^ COSEWIC Assessment and Update Status Report on the Beluga Whale. Dsp-psd.pwgsc.gc.ca (31 July 2012). Retrieved on 2013-03-21. * ^ Cota, Glenn F. (1985). "Photoadaptation of high Arctic ice algae". Nature. 315 (6016): 219. Bibcode :1985Natur.315..219C. doi :10.1038/315219a0 . * ^ A B Parsons, pp. 215–217 * ^ http://www.jqjacobs.net/anthro/paleoamericans.html * ^ Parsons, p. 222 * ^ Tuktoyaktuk – Statistical Profile. stats.gov.nt.ca * ^ A B Parsons, p. 233 * ^ A B Marlan W. Downey, William Andrew Morgan, Jack C. Threet, American Association of Petroleum Geologists Petroleum provinces of the twenty-first century, AAPG, 2001 ISBN 0-89181-355-1 , p. 125 * ^ Hawkings, T.J.; Hatfield, W.G.; Bowerman, J.N.; Coffman, R.C. (1976). Braunstein, Jules, ed. Taglu Gas Field, Beaufort Basin, Northwest Territories, in North American Oil and Gas Fields. Tulsa: The American Association of Petroleum Geologists. pp. 51–71. ISBN 0891813004 . * ^ David L. VanderZwaag, Cynthia Lamson The Challenge of arctic shipping: science, environmental assessment, and human values, McGill-Queen's Press – MQUP, 1990 ISBN 0-7735-0700-0 , p. 61

BIBLIOGRAPHY

* L. S. Parsons, William Henry Lear, National Research Council of Canada
Canada
Perspectives on Canadian marine fisheries management, NRC Research Press, 1993 ISBN 0-660-15003-4

FURTHER READING

* David G. Barber; Ryan Galley; Matthew G. Asplin; Roger De Abreu; Kerri-Ann Warner; Monika Pu?ko; Mukesh Gupta; Simon Prinsenberg & Stéphane Julien (2009). "Perennial pack ice in the southern Beaufort Sea
Sea
was not as it appeared in the summer of 2009". Geophysical Research Letters. 36 (24): L24501. Bibcode :2009GeoRL..3624501B. doi :10.1029/2009GL041434 . * Dawn Russell (1992). "International Ocean
Ocean
Boundary Issues and Management Arrangements". In David VanderZwaag. Canadian Ocean
Ocean
Law and Policy. Toronto: Butterworths. pp. 463–505. * Donat Pharand (Autumn 1984). "The Legal Regime of the Arctic: Some Outstanding Issues". International Journal. 39: 742–799. doi :10.2307/40202296 . * Karin L. Lawson (1981). "Delimiting Continental Shelf Boundaries in the Arctic: The United States— Canada
Canada
Beaufort Sea
Sea
Boundary". Virginia International Law Journal. 22: 221–246.

EXTERNAL LINKS

* Sea
Sea
Ice in the Beaufort Sea
Sea
from NASA Earth Observatory * CAC (Civil Applications

.