Kuroshio current

In the 1970s, the Sagami Chemical Research Center in Japan provided nutrient reference material for the Cooperative Study of the Kuroshio Current (the so-called CSK standards). These solutions were not prepared in seawater, which limits their general utility (see below), however they are still distributed and widely used as a common reference. French and British scientists have conducted some studies on nutrient reference material (Aminot and Keroul, 1991, 1996 Zhang et al., 1999) with limited success. 

Ocean. The former is estimated to have a surface area the size of Texas. The focusing effect of the Kuroshio Current on the density of plastics collected in plankton net tows is shown in Figure 28.35. In some locations, particle densities are greater than that of the local zooplankton. High concentrations have also been reported on the seabed near industrialized areas such as the Mediterranean and the North Seas. In 2000, the volume of litter estimated to be residing on the seabed of the North Sea was 600,000 m. ... 

Locations of stations sampied for piastic in 2000-2001. (a) Distribution and abundance (pieces/km ) of totai piastics in the Kuroshio Current area, (b) Sampies were coiiected by a surface tow using a neuston net (mouth opening 50 x 50cm side iength 3m mesh size 330. m). The numericaiiy dominant size class (62%) was 1-3 mm. Broken iine in (b) denotes the Kuroshio flow path during the study period. Source From Yamashita, R., and A. Tanimura (2007). Marine Pollution Bulletin 54, 464-488. 

Chen, Y.-L., Lu, H.-B., Shiah, F.-K., Gong, G. C., Liu, K.-K., andKanda,. (1999). New production and f-ratio on the continental shelf of the East China Sea Comparisons between nitrate inputs from the subsurface Kuroshio Current and the Changjiang River. Estuar. Coast. Shelf Sd. 48, 59—IS. 

Gomez et al. (2005) observed the Chaetoceros-Richelia (note these authors use an alternative nomenclature) symbioses was restricted to the transition zones between the slope waters and the Kuroshio Current in the western Pacific Ocean. They proposed that their distribution was related to local mixing of the Kuroshio Current with the coastal waters, where Chaetoceros is a dominant member of the neritic phytoplankton population. 

Okinawa is Japan s southernmost prefecture, and consists of hundreds of islands known as the Ryukyus, in an island chain over 1000 km long, which extends southwest from Kyusyu (the southwestemmost of Japan s main four islands) to Taiwan. The warm waters of the Kuroshio Current have developed and sustained the coral reefs of Okinawa, which are among biologically the most diverse and the richest coral reefs in the world. 

The maximum displacement from line AB was observed in area C, east of Lutao (Figure lb). This displacement was most likely caused by an eastward component of the Kuroshio Current. The shape of the spill in area C is similar to the shape of feature 4. The interaction of the Kuroshio flow with Lutao and underwater rising around it were responsible for the appearance of both feature 4 and the eastward component of the current. The change in velocity of this component with distance manifested itself as the shape of departure y(x). The maximum displacement was found at a dis-... 

The cyclonic eddy-like structures, similar to eddies 10 and 15 (Figure la) and 9-11 (Figure 4), are typical of the Kuroshio Current area east of Taiwan. They have been detected on many ERS-1/2 SAR images however, their position is variable. These eddies were observed due to their radar contrast against the background and/or the presence of definite structures (narrow spiral lines), resulting from the modulation of surface roughness by variable currents. Filamentary slicks were much less common here to favour their detection. Estimates of the current velocity for two eddies obtained by the analysis of the oil spill displacements were found to be 0.07-0.08 ms"1 and 0.3 ms"1. 

The East China Sea circulation is dominated by the northward flow of two loops of the Kuroshio Current (KC) the Taiwan Warm Water (TWW) in the west and the Yellow Sea Warm Water (YSWW) in the east. Both water masses are characterized by high salinity and warm water temperatures. In contrast, a southward flow in close to sea bottom water occurs from the flow of the Changjiang (CJCW) and Jiangsu Coastal Waters (JCW) along the Chinese coast, the Korean Coastal Waters (KCW) in the east, and the Yellow Sea Cold Waters (YSCW) in the north (Fig. 1.30, Lee and Chao, 2003). The coastal currents in particular appear as seasonally cold and brackish water masses. 

To the east of ECS, the Kuroshio Current, a strong western boundary current, flowing along the Pacific Margin of northeastern Asia, borders the shelf slope of the East China Sea. When passing through the ECS, it has... 

Chen CTA, Liu CT, Pal SC (1994) Transport of oxygen, nutrients and carbonates by the Kuroshio current. Chin J Oceanol Linrnol 12(3) 220-227... 

In the ECS continental shelf surface sediments, carbonate is the most abim-dant in the outer continental shelf sediments (Lin et al., 2002b). The highest content, up to 90%, was found in the area where the Kuroshio Current intruded on the ECS continental shelf. Common carbonate content on the shelf is in the range of 10% to 30%. Values greater than 25% were observed mostly in areas directly under the path of the Kuroshio Current. Most sediments are biogenic carbonate along the southeastern part of the outer shelf (Gao et al., 2006). This resulted in that the carbonate is rich in coarse sediment and poor in fine sediment (Fig. 4.11, Yang et al., 2002). 

Once in the ocean, the tides and currents driven by wind control the circulation of shallow water. Seven major currents, shown in Figure 2.1 [27], move water around the globe the West Wind Drift (or the Antarctic Circumpolar Current), East Wind Drift, the North and South Equatorial currents, the Peru Current, the Kuroshio Current, and the Gulf Stream. These currents can move quickly. The Gulf Stream, for example, usually travels at a speed of 3 or 4 knots, which is equivalent to 5.6 to 7.4 kilometers per hour [27]. As these currents spiral through the ocean they form five major gyres the North Atlantic, South Atlantic, North Pacific, South Pacific, and Indian Ocean gyres. 

Yamashita, R. and Tanimura, A. (2007) Floating Plastic in the Kuroshio Current Area, Western North Pacific Ocean , Marine Pollution Bulletin 54 485-88. 

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