Kuroshio
The Kuroshio ( Japanese 黒 潮 , dt. Black Current ; also called Japan Current) is a surface ocean current in the western Pacific . It is the extension of the north-flowing Pacific North Equatorial Current between Luzon in the Philippines and the east coast of Japan . The water temperature is very high for this region at around 20 ° C, the salinity is 3.45%. The Kuroshio transports an average volume flow of 25 Sv .
The current passes Taiwan (the former Formosa) and the Ryūkyū Islands before flowing around the coast of Kyushu , where foothills turn west in the summer months and then pass northeast through the Strait of Korea to parallel the coast of Honshū as the Tsushima Current the sea of Japan to cross. The transport volume of the Tsushima is comparatively low at 2 Sv.
The bulk of the Kuroshio flows east to Japan over and meet in the area around 35 ° N on the south flowing Oyashio . Together, the two ocean currents form the North Pacific Current (North Pacific west wind drift). To the west of the Hawaiian Islands this current loses much of its energy and forms the countercurrent to the Kuroshio as a giant vortex, which merges with the Pacific North Equatorial Current further south and thus returns the water to the cycle.
Extensions of the original stream continue eastward and split into the Alaska Stream and the California Stream .
The Kuroshio is subject to seasonal fluctuations in its flow behavior. The current is strongest in the spring months with ~ 30 Sv. In late summer and autumn the current becomes weaker (~ 19 Sv), in January and February it increases again, although a small weakening can be seen in the beginning of spring.
As a sea current, the Kuroshio has a similarly important climate-determining effect for Japan as the Gulf Stream in the Atlantic has for Europe . From the southern tip of the Japanese islands, the warming effect extends north to the Tokyo region .
The Kuroshio has been known to Europeans since around 1650, as a map by Bernhardus Varenius shows. It is also listed in the records of Captain J. King, a member of the James Cook (1776-80) expedition . The name Kuroshio (Black Stream) comes from the color of the water, which contrasts with the surrounding water through its dark to almost black color.