Midnattssol in english is which natural phenomenon that occurs in the summer months in places north of the Arctic Circle or south of the Antarctic Circle?
Midnight sun The midnight sun is a natural phenomenon that occurs in the summer months in places north of the Arctic Circle or south of the Antarctic Circle, when the sun remains visible at the local midnight. Around the summer solstice (approximately 21 June in the Northern Hemisphere and 22 December in the Southern Hemisphere) the sun is visible for the full 24 hours, given fair weather. The number of days per year with potential midnight sun increases the closer towards either pole one goes. Although approximately defined by the polar circles, in practice the midnight sun can be seen as much as 55 miles (90 km) outside the polar circle, as described below, and the exact latitudes of the farthest reaches of midnight sun depend on topography and vary slightly year-to-year.
Ekman transport Ekman transport, part of Ekman motion theory first investigated in 1902 by Vagn Walfrid Ekman, is the term given for the 90° net transport of the surface layer of a fluid (the layer affected by wind) by wind forcing. This phenomenon was first noted by Fridtjof Nansen, who recorded that ice transport appeared to occur at an angle to the wind direction during his Arctic expedition during the 1890s. The direction of transport is dependent on the hemisphere: in the northern hemisphere, transport occurs at 90° clockwise from wind direction, while in the southern hemisphere it occurs at a 90° counterclockwise.