Drift ice in the context of "Pressure ridge (ice)"

Peter I Island (Norwegian: Peter I Øy) is an uninhabited volcanic island in the Bellingshausen Sea, 450 kilometres (240 nmi) from continental Antarctica. It is claimed as a dependency of Norway and, along with Bouvet Island and Queen Maud Land, composes one of the three Norwegian dependent territories in the Antarctic and Subantarctic. The island measures approximately 11 by 19 kilometres (7 by 12 mi), with an area of 156 km (60 sq mi); its highest point is the ultra-prominent, 1,640-metre-tall (5,380 ft) Lars Christensen Peak. Nearly all the island is covered by a glacier, and it is surrounded most of the year by pack ice, making it inaccessible during these times. There is little vertebrate animal life on the island, apart from some seabirds and seals.

The island was first sighted by Fabian Gottlieb von Bellingshausen on 21 January 1821 and was named after Peter I of Russia. Not until 2 February 1929 did anyone set foot on the island, when Nils Larsen and Ola Olstad's Second Norvegia Expedition, financed by Lars Christensen, was successful. They claimed it for Norway, which annexed it in 1931 and made it a dependency in 1933. The next landing occurred in 1948, and the island has been subject to some scientific research and a limited amount of tourism. The island became subject to the Antarctic Treaty in 1961. Since 1987, there has been an automated meteorological station on the island. Three amateur radio DX-peditions have visited the island, and there are sporadic landings by tourists.

Antarctic sea ice is the sea ice of the Southern Ocean. It extends from the far north in the winter and retreats to almost the coastline every summer. Sea ice is frozen seawater that is usually less than a few meters thick. This is the opposite of ice shelves, which are formed by glaciers; they float in the sea, and are up to a kilometre thick. There are two subdivisions of sea ice: fast ice, which are attached to land; and ice floes, which are not.

Sea ice that comes from the Southern Ocean melts from the bottom instead of the surface like Arctic ice because it is covered in snow on top. As a result, melt ponds are rarely observed. On average, Antarctic sea ice is younger, thinner, warmer, saltier, and more mobile than Arctic sea ice. Another difference between the two ice packs is that while there is clear Arctic sea ice decline, the trend in Antarctica is roughly flat. Antarctic sea ice is not studied very well in comparison to Arctic ice since it is less accessible.

A drifting ice station is a temporary or semi-permanent facility built on an ice floe. During the Cold War the Soviet Union and the United States maintained a number of stations in the Arctic Ocean on floes such as Fletcher's Ice Island for research and espionage, the latter of which were often little more than quickly constructed shacks. Extracting personnel from these stations proved difficult and in the case of the United States, employed early versions of the Fulton surface-to-air recovery system.

Foxe Basin is a shallow oceanic basin north of Hudson Bay, in Nunavut, Canada, located between Baffin Island and the Melville Peninsula. For most of the year, it is blocked by sea ice (fast ice) and drift ice made up of multiple ice floes.

The nutrient-rich cold waters found in the basin are especially favourable to phytoplankton and the numerous islands within it are important bird habitats, including Sabine's gulls and many types of shorebirds. Bowhead whales migrate to the northern part of the basin each summer.

The fin whale (Balaenoptera physalus), also known as the finback whale or common rorqual, is a species of baleen whale and the second-longest cetacean after the blue whale. The biggest individual reportedly measured 26–27 m (85–89 ft) in length, with a maximum recorded weight of 65.5 to 80 tonnes (72.2 to 88.2 short tons; 64.5 to 78.7 long tons). The fin whale's body is long, slender and brownish-gray in color, with a paler underside to appear less conspicuous from below (countershading).

At least two recognized subspecies exist, one in the North Atlantic and one across the Southern Hemisphere. It is found in all the major oceans, from polar to tropical waters, though it is absent only from waters close to the pack ice at the poles and relatively small areas of water away from the open ocean. The highest population density occurs in temperate and cool waters. Its prey mainly consists of smaller schooling fish, small squid, or crustaceans, including copepods and krill. Mating takes place in temperate, low-latitude seas during the winter. Fin whales are often observed in pods of 6–10 animals, with whom they communicate utilizing frequency-modulated sounds, ranging from 16 to 40 hertz.

Fast ice (also called land-fast ice, landfast ice, and shore-fast ice) is sea ice or lake ice that is "fastened" to the coastline, to the sea floor along shoals, or to grounded icebergs. Fast ice may either grow in place from the sea water or by freezing pieces of drifting ice to the shore or other anchor sites. Unlike drift (or pack) ice, fast ice does not move with currents and winds.

The width (and the presence) of this ice zone is usually seasonal and depends on ice thickness, topography of the sea floor and islands. It ranges from a few meters to several hundred kilometers. Seaward expansion is a function of a number of factors, notably water depth, shoreline protection, time of year and pressure from the pack ice. In Arctic seas the fast ice extends down to depths of 20 m (65.6 ft), while in the Subarctic seas, the zone extends to depths of about 10 m (32.8 ft). In some coastal areas with abrupt shelf and no islands, e.g., in the Sea of Okhotsk off Hokkaidō, tides prevent the formation of any fast ice. Smaller ocean basins may contain only the fast ice zone with no pack ice (e.g. McMurdo Sound in Antarctica).

An ice floe (/floʊ/) is a segment of floating ice defined as a flat piece at least 20 metres (66 ft) across at its widest point, and up to more than 10 kilometres (6.2 miles) across. Drift ice is a floating field of sea ice composed of several ice floes. They may cause ice jams on freshwater rivers, and in the open ocean may damage the hulls of ships.

Ice floes pose significant dangers due to their instability, unpredictability, and susceptibility to environmental forces. Unlike thick, grounded ice, floes are buoyant and mobile, drifting with ocean currents and winds at variable speeds. This movement can rapidly separate a floe from the shoreline or from other floes, trapping individuals or wildlife with no means of return. Structurally, ice floes are often riddled with hidden fractures and varying thickness, making them prone to sudden breakage or collapse under weight. Additionally, temperature fluctuations can weaken their integrity, while tidal shifts and wave action can cause tilting or rolling, creating crushing forces or ejecting occupants into frigid, hypothermia-inducing waters. For vessels, ice floes present navigational hazards as collisions with even modest floes can damage hulls or jam propellers, especially in poorly reinforced ships.