Territorial claims in Antarctica south of the Straits of Magellan (Terra Australis, and Tierra del Fuego and by extension the entire continent of Antarctica). This grant established, according to Argentina and Chile, that an "animus occupandi" existed on the part of Spain in Antarctica. Spain's sovereignty claim over parts of Antarctica was, according to Chile and Argentina, internationally recognized with the "Inter caetera" bull of 1493 and the Treaty of Tordesillas of 1494. Argentina and Chile treat these treaties as legal international treaties mediated by the Catholic Church that was at that time a recognized arbiter in such matters. Each country currently has claim
West Antarctica Year (1957–1958) and explorations which disclosed that the Transantarctic Mountains provide a useful regional border between West Antarctica and East Antarctica. Advisory Committee on Antarctic Names (US-ACAN) approved the name in 1962. West Antarctica is mostly covered by a massive ice sheet referred to as the West Antarctic Ice Sheet (WAIS). In recent decades this ice sheet has shown signs of decreasing mass. Unlike East Antarctica, West Antarctica has shown some effects of global warming. The parts of West Antarctica not covered with ice (Antarctic oasis), which are the coasts of the Antarctic Peninsula, constitute a biodiversity region known as