Antarctic circumpolar current

Smetacek, V., de Baar, H. J. W., Bathmann, U. V. et al. (eds) (1997). Ecology and biogeochemistry of the Antarctic Circumpolar current during austral spring Southern Ocean JGOFS Cruise ANT X/6 of R.V. Polarstem. Deep-Sea Res. II44,1-519. 

Fig. 6 Geographic origin of the four P. antarctica strains (Table 2). To indicate the position of the Antarctic circumpolar current (ACC) encircling the Antarctic a schematic presentation was chosen (Lange et al. 2002 Olbers et al. 1962). [1 SK21, 2 SK22,3 D5, 4 Al-3]...

Coale KH, Wang X, Tanner SJ, Johnson KS (2003) Phytoplankton growth and biological response to iron and zinc addition in the Ross Sea and Antarctic Circumpolar Current along 170°W. Deep Sea Res II 50 635-653... 

Vaillancourt RD, Marra J, Barber RT, Smith WO Jr (2003) Primary productivity and in situ quantum yields in the Ross Sea and Pacific Sector of the Antarctic Circumpolar Current. Deep-Sea Res II 50 559-578 van Leeuwe MA, Stefels J (1998) Effects of iron and light stress on the biochemical composition of Antarctic Phaeocystis sp. (Prymnesiophycea). II. Pigment composition. J Phycol 34 496-503... 

Law, C. S., and Ling, R. D. (2001). Nitrous oxide flux and response to increased iron avadabdity in the Antarctic Circumpolar Current. Deep-Sea Res. 7/48, 2509—2527. 

The NO3 content of upweUing water is strongly influenced by the location of a system (Codispoti et al., 1982) in the global oceanic conveyer belt that transports deep water through the ocean basins (Broecker and Peng, 1982, their Fig. 1.12). From the North Atlantic to the Pacific and Indian Oceans through the Antarctic Circumpolar Current, there are increasing nutrients, from the faUout of surface productivity. 

Paleoproductivity studies in the Southern Ocean, where the deep-reaching Antarctic circumpolar current causes substantial sediment redistribution, have been especially dependent on the °Th-profiling method to obtain accumulation rates of opal, excess barium, organic carbon, and other paleoproductivity proxies (Anderson et al., 2002, 1998 Chase et al., 2003a Francois et al., 1997, 1993 Frank, 1996 Frank et al., 2000 Kumar et al., 1995). Studies of the Atlantic and Indian sectors of the Southern Ocean concluded that productivity in regions south of the Antarctic polar front was lower... 

Frank M. (1996) Reconstructions of Late Quaternary environmental conditions applying the natural radionucUdes Th, e, Pa and a study of deep-sea sediments from the eastern sector of the Antarctic Circumpolar Current System. Rep. Polar Res. 186, 1—136. 

Friedrich J. and Rutgers van der Loeff M. M. (2002) A two-tracer ( Po- Th) approach to distinguish organic carbon and biogenic silica export flux in the Antarctic Circumpolar Current. Deep-Sea Res. I Oceanogr. Res. Pap. 49(1), 101-120. 

Figure 5.1. Approximate circumpolar paths of the principal fronts within the Antarctic Circumpolar Current based on historical data compilation. Adapted from Whitworth (2).

As the Antarctic Bottom Water flows north, it gradually mixes with the southward flowing North Atlantic Deep Water, which lies immediately above. As the North Atlantic Deep Water flows to the south, it incorporates not only the Antarctic Bottom Water but also the Mediterranean Water and the Antarctic Intermediate Water which lie above. The North Atlantic Deep Water is eventually entrained into the Antarctic Circumpolar Current and flows unimpeded into the Indian and Pacific Oceans. 

Fig. 1.19 Distribution of major sediment facies across the frontal system of the Antarctic Circumpolar Current (ACC) between Africa and Antarctica. Numbers are typical sedimentation rates in mm kyh PF = Polar Front, SAF = Sub Antarctic Front, STF = Subtropical Front.

The deep-water temperature cooling across the Eocene/Oligocene boundary (Figure 7B) was not accompanied by tropical cooling, and resulted from the first step in the thermal isolation of Antarctica. In modern ocean, the Antarctic Circumpolar Current is a vigorous surface-to-bottom current that provides... 

Stable carbon isotopes data—As shown in Table 2 and Fig. 3, the extracted sediment residue exhibits value (—24.24%o) which is lower than the SMB sediment (—22.41%o) and Southern Ocean site in the South Pacific sector in the Antarctic Circumpolar Current region (Wang and Druffel, 2001) but falls within the range of values, —23.90 to —26.50%o, obtained from the unextracted sediments earlier from the same region (Venkatesan, 1988) and from the Ross Ice Shelf (Sackett, 1986). The lower values are characteristic of mixed inputs from the cold water plankton, especially the diatom-ooze and older recycled kerogen from the shale fragments (Sackett, 1986). With the exception of ketone and aliphatic fractions, all other lipid fractions have a lower value in the... 

In remote regions of the open ocean that receive little atmospheric input, the vertical transport of iron-rich deep waters is particularly important [73,156]. The primary source of iron to the Fe-limited Southern Ocean is entrainment of Fe-enriched water during deep winter mixing, augmented by the summer upwelling of circumpolar deep water at the Polar Front and the southern front of the Antarctic Circumpolar Current [119,155,157]. 

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