Project MIZPAC (Marginal Ice Zone Pacific) was initiated in 1971 by the Arctic Submarine Laboratory, San Diego, California, to further the US Navy's understanding of problems associated with operating submarines under ice-covered oceans. Oceanographers from the Naval Postgraduate School took part in six summer cruises to the marginal sea ice zone (MIZ) of the shallow Chukchi Sea between 1971 and 1978 (Fig 1), providing the first detailed observations of the temperature-salinity structure within this dynamically active zone. Strong horizontal gradients of temperature and salinity marking boundaries between water masses (fronts), are widespread and well developed (Paquette and Bourke 1981). Where water masses intrude upon each other large-scale temperature inversions (anomalous increases in temperature with depth) often appear. Termed fine structure, these temperature anomalies include some of the largest observed anywhere in the world's oceans, sometimes exceeding 2°C over vertical distances of 5–10 m (Paquette and Bourke 1979). This article describes some of the fronts and fine structures observed in the Chukchi Sea, and shows how they develop within the general patterns of sea ice and circulation.

In the present era of instantaneous telecommunications it is scarcely conceivable that two major exploring or scientific expeditions could be planning simultaneously to operate in a particular area of the Arctic (or indeed anywhere on earth) in complete ignorance of each other's intentions until each arrived in the field. At the turn of the century, however, this was indeed possible, and did in fact happen in the case of a little-known expedition to Ellesmere Island, led by Dr Robert Stein, which found itself completely eclipsed by the much better equipped and funded expedition of Otto Sverdrup in Fram.

The hunt for Bowhead Whales Balaena mysticetus has for centuries been a tradition in the culture of coastal Alaskan Eskimos. Commercial hunting began in 1848, when the first American whaling vessel, under Captain Thomas Roys, worked northward through the Bering Strait and started pelagic whaling in the Arctic Ocean. This fishery ended about 1914, because of severe depletion of the stock. However, Eskimos continued to hunt the remaining whales, using traditional boats and skills augmented by methods and equipment acquired from Yankee whalers. They still carry on the hunt today, using essentially the same methods; the right of native Alaskans to hunt in this way is permitted by US domestic legislation relating to marine mammals and endangered species (Mitchell and Reeves 1980).

The six men of Captain Robert Falcon Scott's Northern Party were stranded on Inexpressible Island (Fig 1) from late February to September 1912. During that period their lives were profoundly influenced by prevailing surface wind and sea ice conditions in Terra Nova Bay. Members of the party lived under the most primitive conditions, enduring more than seven months of strong, persistent winds. The western part of Terra Nova Bay remained largely free of ice in 1912, thus preventing the group from leaving until there was sufficient daylight to cross the Drygalski Ice Tongue. This open water, however, may also have assured their survival for it attracted enough seals and penguins to provide them with a continual though limited supply of food. Despite these adverse conditions some of the men, Raymond Priestley in particular, kept detailed journals which provide the only in situwintertime observations for this area. Analysis of Priestley's wind and ice record provides strong confirmation of our model for the wintertime persistence of open water (a polynya) in Terra Nova Bay.

On the afternoon of 13 March 1931 a massively-built icebreaker could be seen smashing her way through the ice in the shipping channel off Pointe-aux-Trembles at the east end of Montreal Island. The name on her bows was Mikula (Montreal Gazette, 1931a, p 23). The following afternoon, accompanied by the smaller icebreaker Saurel, she pulled alongside at the Imperial Oil Company's wharf in Montreal East, to be met by a large crowd, led by the Minister of Marine and Fisheries, the Honourable Albert Duranleau (Montreal Gazette, 1931b, p 21). Captain John Hearn welcomed the minister on board, then took him and his party out among the river ice to show off Mikula's paces. The cause of all the excitement was that Mikula had reached Montreal 15 days earlier than the previous record, set by the icebreaker Lady Grey in 1921. Hence Montreal had come a significant step closer to her present situation of being a year-round port.

Few wars have a more misleading name than the Crimean War. Far from being a local conflict, fought in the Black Sea peninsula from which the name derives, hostilities took place in many different areas of the globe. Major military operations, largely between Turks (siding with Britain and France) and Russians, occurred in the Balkans and the Caucasus, and a considerable naval effort was made by the British and French to prosecute the war against Russia in the Baltic and Black seas, and also in the Far East and the Pacific (Stephan 1969). The war even reached North America; elements of the Royal Navy reconnoitred Russian settlements in Alaska in 1855 (Tyrrell 1856, 2: 355).

On 28 November 1979 an Air New Zealand DC 10 aircraft on sight-seeing flight TE901 crashed into Mount Erebus, Ross Island in the Ross Dependency, Antarctica, killing all 257 people on board. The disaster and its subsequent investigation are of considerable concern not only for the New Zealand legal system, but also for the nascent discipline of Antarctic law (Auburn 1982).

Karl Weyprecht has left an unforgettable record of polar exploration, but has himself tended to be forgotten. His fame rests not so much with his work in the Arctic, which included the discovery of Zemlya Frantsa-Iosifa, but on the series of international scientific programmes which he initiated in 1875 with the first International Polar Year (IPY), 1882–83. International scientific programmes can be traced back to 1751, when observations of the parallaxes of the Moon, Mars and Venus were made at six stations in the Northern Hemisphere and at one in the Southern. The most recent, the World Climate Research Programme, organized jointly by the World Meteorological Organization (WMO) and the International Council of Scientific Unions (ICSU), began in 1980.

The most ambitious field project of the 1979–80 austral summer season in Antarctica was conducted in the Ellsworth Mountains (Fig 1), when 42 scientists and technicians studied a variety of geological problems in an area which included both the Sentinel Range to the north and the Heritage Range to the south (Fig 2), from about 77°15'S to 80°30'S and 80°W to 87°30'W.

World War I has often been said to mark the end of the ‘Age of Imperialism’—the close of ‘that final surge of land hunger’ (Landes 1969) from 1880 to 1914 when much of the world's land surface, especially in Africa and the Pacific, was acquired by the major powers. Britain's large share was demonstrated by the predominance of red on pre-1914 maps, though in fact the British Empire achieved its greatest area after 1918; ‘… including India’, reported the 1920 Colonial Office List, ‘the Empire now extends over 11 million of square miles, or 91 times the area of the Mother Country’ (Mercer 1920). This study examines one specific part of British imperial policy in the immediate post-war years—one which, had it been fully implemented, would have increased the area by a further 40 per cent. In the view of L. S. Amery, Under-Secretary of State at the Colonial Office and one of Britain's leading politicians of the time, it was desirable that:

… the whole of the Antarctic should ultimately be included within the British Empire, and that, while the time has not yet arrived that a claim to all the continental territories should be put forward publicly, a definite and consistent policy should be followed of extending and asserting British control with the object of ultimately making it complete.

In May 1982, with the successful conclusion of FRAM IV, the Office of Naval Research (ONR) completed the FRAM series of observations from ice floe stations in the eastern Arctic (Fig 1)—expeditions initiated each spring from 1979 to 1982. The programme developed from an unsuccessful attempt by the Arctic Programme of the ONR to duplicate Fridtjof Nansen's drift of the FRAM across the Arctic. This was to have involved freezing the icebreaker USCGC Burton Island in the pack ice of the Laptev Sea, but the programme was cancelled due to lack of support. Arctic scientists meeting at the Third Symposium on Antarctic Geology and Geophysics at Madison, Wisconsin, decided on an alternative programme involving ice floe stations. Named FRAM in honour of Nansen's vessel (Hunkins and others 1979a; Kristoffersen 1979), this was eventually organized by the Arctic Programme of ONR to provide basic environmental data from the eastern Arctic north of Greenland. From its inception FRAM emphasized multi-disciplinary research by scientists of several nations. The stations were under US management, with logistics coordinated by the Polar Research Center, University of Washington, under ONR contract. Danish scientists were involved through the Commission for Scientific Research in Greenland, Norwegians through the Norsk Polarinstitutt, British scientists through the Scott Polar Research Institute, and Canadians through the Bedford Institute of Oceanography. Each expedition emphasized a particular scientific discipline with supporting programmes: below are listed the dates, major studies (priority discipline first), chief scientists and key data reports of each.

The United States and Canada, like other northern industrial nations, are under considerable economic pressures to develop their indigenous resources of oil and natural gas. Incentives for exploration and development are provided by increases in the price of fuels on world markets and political instability in the Middle East, the major alternative source of supply. The Arab oil embargo of 1973–74 quadrupled prices per barrel from US$3.00 to US$12.00 in less than a year; since then the price on world markets has trebled and remains unstable. Searches for new sources of energy in the far north have led firstly to the discovery of major shore-based fields (for example those centred on Prudhoe Bay), and the extension of old ones (Norman Wells), and more recently to important developments off-shore. Many new sites are now being explored, and to date over two billion dollars have been spent by the US and Canada, to find and develop Arctic offshore wells. As yet not a cent has been earned in return, largely because there are at present no means of delivering the petroleum from offshore sites—no safe and reliable system of transportation equivalent to the pipelines from shore-based sites. Industry and government are considering alternatives, but no full-scale construction or procurement programmes have yet been launched.