Bear Island (Norway) - Hydrography, Geography and Climate

Hydrography, Geography and Climate

Agencies of the Norwegian government have conducted Hydrographic surveys of the waters of Svalbard throughout the 20th century, namely "Norges Svalbard- og Ishavsundersøkelser" since 1928, its successor, the Norwegian Polar Institute since 1948, and the Norwegian Hydrographic Service since 1984. Land surveying and mapping are the responsibilities of the Polar Institute.

Bear Island lies 235 kilometres (146 mi) south of mainland Spitsbergen and 397 kilometres (247 mi) NNW of Ingøy in mainland Norway. In the westernmost part of the Barents Sea on Spitsbergen Bank, which extends southward from Spitsbergen and Edgeøya, forming a part of the continental shelf. Water depths near the island and to the north and east do not much exceed 100 metres (328 ft), but become much greater to the south, and especially some thirty nautical miles to the west, where the continental shelf slopes into the deep water of the Norwegian Sea and Greenland Sea.

The island's outline is an irregular triangle pointing south with a greatest north-south extension of 20 kilometres (12 mi) and a greatest east-west extension of 15.5 kilometres (9.6 mi); its surface area is 178 square kilometres (69 sq mi). The southern part of Bjørnøya is mountainous, the highest top being Miseryfjellet on the southeast coast at about 536 metres (1,759 ft) above sea level. Other notable mountains are Antarcticfjellet in the southeast, and Fuglefjellet, Hambergfjellet, and Alfredfjellet in the southwest. The northern part of the island forms a lowland plain that comprises some two thirds of the surface area. The lowland is strewn with shallow freshwater lakes which cover some 19 square kilometres (7.3 sq mi) in all. Several streams flow into the sea, often as waterfalls in the steeper parts of the coast. There are no glaciers on Bear Island.

Apart from a few sandy beaches, the coast is mostly steep, with high cliffs and notable signs of erosion such as caverns and isolated rock pillars. A number of anchorages and landing points exist, as well as a small harbor at Herwighamna on the north coast. However, none of these are safe in all weather conditions and a ship mooring anywhere on Bear Island must therefore be prepared to weigh anchor at any time.

A branch of the North Atlantic current carries warm water to Svalbard, creating a climate much warmer than that of other regions at similar latitude. Bear Island's climate is maritime-polar with relatively mild temperatures during the winter. January is the coldest month, with a mean temperature of −8.1°C (17.4°F) (base period 1961–1990). July and August are the warmest months, with mean temperatures of 4.4 °C (39.9 °F). Temperatures have tended to be warmer the latest decades. There is not much precipitation, with an average of 371 mm (14.6 in) per year in the northern lowland area. The weather can be quite stable during the summer months, although foggy conditions are common, occurring during 20% of all days in July. Fog develops when warm air of Atlantic origin passes over cold water.

Because Bear Island lies on a boundary between cold water of polar origin and warmer Atlantic water, water temperatures within a few dozen nautical miles of the island are quite variable, sometimes reaching 10 °C (50 °F) in summer. During the winter fast ice develops on the coast, but it is rare on the open sea around Bear Island. The Barents Sea carries pack ice to Bjørnøya every winter, sometimes as early as October, but a significant amount of ice is not common before February.

The polar night lasts from November 8, to February 3, and the period of midnight sun from May 2, until August 11,.