North Pole Since 2002, the Russians have also annually established a base, Barneo, close to the Pole. This operates for a few weeks during early spring. Studies in the 2000s predicted that the North Pole may become seasonally ice-free because of Arctic ice shrinkage, with timescales varying from 2016 to the late 21st century or later. The sea depth at the North Pole has been measured at by the Russian Mir submersible in 2007 and at 4,087 m (13,410 ft) by USS "Nautilus" in 1958. The nearest land is usually said to be Kaffeklubben Island, off the northern coast of Greenland about
Pole to Pole flying there on a small aeroplane fitted with skis. The North Pole scene was filmed in May 1992, after the rest of the series had been shot, as weather conditions were more suitable then as the ice was too fragile the previous year. From there, he heads to Greenland, then the Norwegian island of Spitsbergen, where the towns of Ny Ålesund and Longyearbyen are located. From there he sails across the Barents Sea on a supply ship to the Norwegian port city of Tromsø, where he visits a statue of Roald Amundsen, the first man to reach the South Pole.