Arctic Ocean – The Cold War for the Cold Region
Canada, Russia, the US, Denmark [via Greenland] and Norway are staking claims in the Arctic Ocean, which may contain a quarter of the world's untapped petroleum reserves, and is becoming more accessible due to global warming. Under the Convention on the Law of the Sea, they could acquire rights to Arctic seafloor territory if the areas are linked to their continental shelves. Russia made its claim in 2001, though it will make a resubmission. Canada ratified the Law on the Sea in 2003, so it has to file its claim by 2013. The United States had not ratified the Law of the Sea Convention.
In recent decades, it has been well recognized that published portrayals of the sea floor north of the Arctic Circle, particularly in the deep central basin of the Arctic Ocean, are not totally accurate, and that in certain areas, there are significant discrepancies between observed and charted depths. The principal cause of this situation has been the lack of sounding information needed to construct reliable and detailed charts: certain regions remain inadequately mapped on account of difficult operating conditions, or because critical data sets have not been made available for widespread public use.
The severe climatic and ice conditions in the Arctic Ocean make it difficult to apply some of the existing methods and technologies that are generally easy to use in other oceans, in order to obtain the information that is necessary for establishing the outer limits of the Continental Shelf.
The floor of the Arctic Ocean is characterized by the existence of at least four large submarine elevations that could be considered to be submerged prolongations of the continental margins beyond 200 nautical miles: Chukchi Plateau, Mendeleyev Ridge, Lomonosov Ridge, and Alpha Ridge. Adequate sets of geological and geophysical data, together with bathymetric and morphological information, are seen as critical to establishing that such elevations are indeed natural components of the continental margin.
The U.N. Convention on the Law of the Sea, or UNCLOS, stipulates that any coastal state can claim territory 200 nautical miles from their shoreline and exploit the natural resources within that zone. Nations can also extend that limit to up to 350 nautical miles from their coast if they can provide scientific proof that the undersea continental plate is a natural extension of their territory.
Continental shelf claims beyond 200 nautical miles are made according to the provisions of Article 76 of the Law of the Sea. The implementation of Article 76 rests fundamentally upon the analysis and interpretation of bathymetric and geological information. A 1996 Workshop assembled specialists from the five coastal states that border the Arctic Ocean (Canada, Denmark, Norway, Russia, and the United States of America) to discuss scientific and technical issues relating to the preparation of continental shelf claims beyond 200 nautical miles. During the course of the 1996 Workshop, it was recognized that all five coastal states have valid grounds for developing continental shelf claims beyond their 200 nautical mile limits, and that the possibility, if not the likelihood, existed of overlapping claims between neighbouring states.
Article 76 of UNCLOS specifies a mechanism for extending the limits of the continental shelf beyond the 200 nautical mile exclusive economic zone (EEZ). After ratification of UNCLOS a country has ten years to collect the appropriate information and submit a claim for an extended continental shelf to the United Nations Commission on the Limits of the Continental Shelf (CLCS).
Much of the argument revolves around the underwater Lomonosov Ridge. Mikhail Vasil'evich Lomonosov was the first Russian natural scientist of world importance. His major scientific accomplishment was in the field of physical chemistry, with other notable discoveries in astronomy, geophysics, geology and mineralogy. He founded what became Moscow State University, in 1755. This university, officially named after Lomonosov, is at the apex of the Russian system of higher education.
The Lomonosov Ridge is an undersea chain of mountains rising some 2500 meters above the Arctic floor. Measuring about 1700 km in length, the Lomonosov Ridge is considered to be of continental origin, a sliver that was separated from the Kara and Barents shelves and transported to its present position by sea-floor spreading.
The General Bathymetric Chart of the Oceans (GEBCO, Canadian Hydrographic Service, 1979) served as an authoritative portrayal of the seafloor north of 64°N. The International Bathymetric Chart of the Arctic Ocean (IBCAO) was developed from an accumulation of bathymetric measurements collected during past and modern expeditions. Striking discrepancies between the GEBCO and IBCAO portrayals of the Lomonosov Ridge occur between the North Pole and the Siberian continental shelf. The new model shows a far more complex morphology, with a ridge that is broken into several smaller segments.
Countries have the possibility of claiming the Lomonosov Ridge, a submarine mountain range, as a natural prolongation of their land territory. Bathymetry, seismic and gravity data are needed to substantiate the claim. Out to a distance of 350 nautical miles or further, if coastal states can claim the Lomonosov Ridge as a natural prolongation of land territory, coastal states can exercise specified sovereign rights. These rights include the right to explore and exploit mineral and biological resources on and below the seabed and jurisdiction in matters related to environment and conservation.
The Lomonosov Ridge, which Russia claims is part of their continental shelf, is clearly a separate oceanic seafloor volcanic ridge and thus not part of Russia's continental shelf. The Russian UNCLOS claim over the Arctic Commons Abyssal area adjacent to the edge of their continental shelf was rejected in 2001 by the Commission for the Continental Shelf, as the geological facts proved that the claim had no basis under UNCLOS rules. The geology of the area in question has not changed since the Russian claim was rejected.
Russia's Oceanology research institute has undertaken two Arctic expeditions - to the Mendeleyev underwater chain in 2005 and to the Lomonosov ridge in August 2007 - on orders from the ministry to back Russian claims to the region, believed to contain vast oil and gas reserves and other mineral riches, likely to become accessible in future decades due to man-made global warming. The Natural Resources Ministry said in September 2007 that preliminary results of research carried out by Russian scientists will allow the country to claim 1.2 million sq km (460,000 sq miles) of potentially energy-rich Arctic territory. On 04 October 2007 Russia's natural resources minister said the development of the Lomonosov underwater mountain chain in the Arctic could bring Russia up to 5 billion metric tons of equivalent fuel. "Reaching the Lomonosov ridge means for Russia potentially up to 5 billion tons of equivalent fuel," Yury Trutnev said
In August 2008 Canadian researchers teamed with Danish scientists to offer proof that the Lomonosov Ridge is a natural extension of the North American continent. Their landmark findings, the initial result of years of sea floor mapping and millions of dollars in research investments by the Canadian and Danish governments, were presented at the 2008 International Geological Congress in Oslo under the innocuous title "Crustal Structure from the Lincoln Sea to the Lomonosov Ridge, Arctic Ocean."
Denmark hopes to collect evidence that will support a claim that the continental shelf of Greenland-a province of Denmark-extends to the North Pole. Norway is the only other country (besides Russia) that has filed a legal claim to extend its continental shelf into a portion of the Arctic Ocean.
Arctic sea ice during the 2007 melt season plummeted to the lowest levels since satellite measurements began in 1979. The average sea ice extent for the month of September was 4.28 million square kilometers (1.65 million square miles), the lowest September on record, shattering the previous record for the month, set in 2005, by 23 percent.
Arctic sea ice receded so much that the fabled Northwest Passage completely opened for the first time in human memory during 2007. Explorers and other seafarers had long recognized that this passage, through the straits of the Canadian Arctic Archipelago, represented a potential shortcut from the Pacific to the Atlantic. Roald Amundsen began the first successful navigation of the route starting in 1903. It took his group two-and-a-half years to leapfrog through narrow passages of open water, with their ship locked in the frozen ice through two cold, dark winters. More recently, icebreakers and ice-strengthened ships have on occasion traversed the normally ice-choked route. However, by the end of the 2007 melt season, a standard ocean-going vessel could have sailed smoothly through. On the other hand, the Northern Sea Route, a shortcut along the Eurasian coast that is often at least partially open, was completely blocked by a band of ice in 2007.
In 2007 National Snow and Ice Data Center (NSIDC) Senior Scientist Mark Serreze said, “The sea ice cover is in a downward spiral and may have passed the point of no return. As the years go by, we are losing more and more ice in summer, and growing back less and less ice in winter. We may well see an ice-free Arctic Ocean in summer within our lifetimes.” The scientists agree that this could occur by 2030.
Discovery of oil fields and natural gas in the artic has led to an increased interest in the development of ice-breaking cargo vessels and/or tankers for use in transporting these resources to refineries and consumers at remotely situated markets. The cargo and/or tanker ships must operate efficiently during the transportation of their cargo. In order to operate efficiently, they must maintain a satisfactory speed with a relatively low fuel consumption. In order to meet these efficiency requirements, conventional ship designs have been developed. Such conventional designs have a low value of ship-ice resistance per unit cargo capacity. Such conventional designs are generally characterized by a relatively large length-to-beam ratio, fine bow forms and long parallel middle-body sections. Such hull designs allow the ship to perform efficiently during normal travel through non-ice-covered waters, and to perform well during straight travel through ice-covered waters. However, due to their relatively long parallel middle body sections, these conventional ships have poor maneuverability in ice-covered waters. The poor maneuverability of the conventional design has presented serious problems when attempting to turn these ships in order to change course in ice-covered waters to avoid objects, such as a major ice ridge or for maneuvering the ship into a docking facility. Accordingly, the poor maneuverability of such conventional designs within ice-covered waters deterimentally affects the safe operation and time required to effectively dock and position the vessel.
The progress of a conventional vessel through ice is dependent mainly on the thickness and type of ice; the thrust of the propeller or propellers; the shape of the hull, with particular emphasis on the forward section; and friction between the hull of the vessel and the ice. Should any of the above factors change or be changed then the vessel's performance would change. The ability of a vessel to steer, when operating in ice, is dependent principally on the thickness and characteristics of the ice; the shape of the bow section; the shape of the stern section; the thrust of the propeller and size of the rudder; and possibly of greatest influence, the length of parallel body (straight ship sides). So, although most vessels, other than ice breakers, have trouble in navigating in ice covered waterways, some have a lot more trouble than others, and this difficulty is proportionately increased with ship length.
In order to avoid safety hazards and attempt to minimize the transit time required to specifically maneuver the vessel, some ships have been designed to serve as the primary ice-breaking vessels. Such vessels escort the conventional cargo ships, clearing the path in front of the cargo ship. Such ice-breaking ships must have both a high maneuverability in the ice and cut a wide channel for the cargo vessel in which to follow. The necessary maneuverability, and ability to form a wide channel are made possible by providing such ice-breaking vessels with a stocky, rounded hull with a relatively low length-to-beam ratio, typically in the range of 4.0 to 5.5. The water plane-shape of this type of hull enables a certain degree of turning within the confines of the channel cut by the ship's beam. However, such a high beam-to-displacement ratio makes such a vessel configuration unsuitable as a cargo vessel. The high beam-to-displacement ratio results in a relatively high power requirement per unit cargo capacity which is moved. Furthermore, this high beam-to-displacement ratio results in an increased open water resistance per unit displacement. Therefore, such vessels do not travel efficiently through ice-covered or non-ice-covered waters.
Another design which has been developed in order to increase the maneuverability of a cargo ship in ice-covered waters includes a wide beam forward configuration. The object of the wide beam forward design is to cause the ship's bow to cut a sufficiently wide channel through the ice to allow a relatively narrow middle body and stern to swing outward to either side during a turning maneuver. This concept was embodied in a converted tanker SS Manhattan. While the wide beam forward design does provide a certain degree of improved turning capability in ice-covered waters, it suffers to some extent from the same effects as the stocky, rounded hull escort vessel discussed above. The wide beam forward configuration requires greater propulsion power per unit displacement in order to break through the ice than is required by an equivalent sized ship having a relatively high length-to-beam ratio. Therefore, although the wide beam forward configuration allows for greater maneuverability during turns in ice-covered waters, the design is inefficient for straight forward travel through ice-covered or non-ice-covered waters. The conventional fine hull shape with a long, parallel middle body section is a fuel efficient design. The fuel efficiency of this design is sacrificed to achieve improved maneuverability when the wide beam forward design is utilized.
When the ship is moving straight ahead, the ice is broken by its bow and the unbroken ice tends to hug the sides and develop considerable friction, impeding forward movement. The condition is complicated by the fact that the ice is often "uneven", as a result of channels having been broken and rebroken, with the pieces of ice thrown up into uneven mounds and refreezing in that form. This uneven structure increases the friction and resistance to movement. If straightline movement is difficult, the problem is compounded when the ship tries to turn. In making a turn, under the action of the rudder, the ship pivots about a point about a third of the way from the bow to the stern (this will vary somewhat depending on the design of the vessel and its draft forward as against its draft aft). Bow thrusters are sometimes used to move the bow laterally, but these tend to become fouled in ice and so are not usually employed for winter navigation.
The US Navy has not recently designed surface ships, other than ice breakers, to operate in the Arctic. The problems of ice damage and topside icing when surface ships were operated in high latitudes were handled on an ad hoc basis. From time to time during the design of a new class of surface ships, the issue of ice hardening has arisen. One example was during the design of the Perry (DDG-7) class guided missile frigates. While high latitude operations were envisioned, these ships were heavily cost constrained and the ice hardening characteristic was dropped from consideration during cost tradeoffs.
The Navy and Coast Guard, however, have designed icebreakers, as have commercial interests. Other commercial ships have been designed for ice hardening. Most major classification societies who govern the details of commercial ship hull design have established rules for the design of ship hulls for operations in ice. The American Bureau of Shipping (ABS) would be the relevant classification society for US ship design. ABS Rules require strengthening of the bow and stern areas. Bow mounted sonar domes and arrays in particular would require careful attention. Propellers, rudders, fin stabilizers, and sea chests are also affected by ice operation. The effect of topside icing and a provision to de-ice must also be considered.
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