The Ross Dependency is New Zealand’s wedge shaped territorial claim of an area of Antarctica including the Ross Sea, Ross Ice Shelf, Ross Island, and the Transantarctic Mountains, extending to the South Pole. It was officially claimed by the United Kingdom in 1923 based on discoveries made by early explorers including Ross, Scott and Shackleton; and in the same year had its administration handed over to New Zealand.
Beginning at the latitude 60° South, the Ross Dependency’s boundaries follow the 160° East and 150° West Longitudes as far as the South Pole. While this area makes up a large part of the entire Realm of New Zealand (which also includes New Zealand, Cook Islands, Niue and Tokelau), most of the Ross Dependency is Ocean and the Ross Ice Shelf. Although New Zealand maintains is right of sovereignty over the area, as an original signatory of the Antarctic Treaty, New Zealand maintains a relationship of cooperation with all other nations, setting aside claim disputes.
The Ross Dependency takes its name from Sir James Clarke Ross who originally discovered a way through the Ross Sea to the Ross Ice Shelf in 1841, claiming the area for Britain at the same time. During the heroic era of exploration, famous explorers including Roald Amundsen, Robert Flacon Scott and Ernest Shackleton explored areas of the Ross Dependency, Amundsen and Scott traversing from the Ross Ice Shelf south to reach the South Pole. Sir Edmund Hillary’s party of 1958, laying depots for the first successful continental crossing, was the first to reach the pole over land since Amundsen in 1911 and Scott in 1912, also being the first to use motorised vehicles to do so.
Scott Base and McMurdo Station are the only permanently occupied bases in the Dependency, although Italy uses Zucchelli Station and Germany, Gondwana Station in the summer, and until 1995 New Zealand also had a Dry Valley base, Vanda Station, in the Wright Valley. Cooperation between these bases and the sharing of resources and logistics for scientists of any nationality using these bases ensures the continuation of scientific discovery in Antarctica. Combined, Scott Base and McMurdo station can support over 1300 people in the summer, McMurdo Station providing logistical support for a large area of the continent.
Many unique and important environmental features are found in the Ross Dependency. The Transantarctic Mountains create a 4000km long chain in the Ross Dependency from Oates Land in the north, through the Dry Valleys and Queen Maud Mountains to the south of the Ross Ice Shelf and continuing on across the continent to the Filchner Ice Shelf. The Ross Ice Shelf is itself the largest ice shelf in the world being over 530,000km², ranging from less than 100m thick at its northern end to up to a kilometre thick further south. Mount Erebus on Ross Island is the world’s most southerly active volcano and at 3,795m high, one of the world’s largest. Mount Melbourne, also in the Ross Dependency, is one of the few active volcanoes on the continent. Approximately half of the ice-free areas of Antarctica are in the Ross Dependency. It is in these areas, where water is available to biology for short periods of the year that terrestrial biology grows. Antarctica’s largest expanse of ice-free ground is found in the Dry Valleys, situated in the Ross Dependency.