Polar front

Walter HJ, Rutgers van der Loeff MM, Hoeltzen H (1997) Etrhanced scavenging of Pa relative to h in the South Atlantic south of the Polar front Implicatiotts for the use of the Pa/ h ratio as a paleoproductivity proxy. Earth Planet Sci Lett 149 85-100 Wheatcroft RA (1992) Experimental tests for particle size-dependant biotirrbidation in the deep oceans. Linmol Oceanogr 37(1) 90-104... 

Kirchman, D. L., B. Meon, H. W. Ducklow, C. A. Carlson, D. A. Hansell, and G. Steward. 2001. Glucose fluxes and concentrations of dissolved combined sugars (polysaccharides) in the Ross Sea and Polar Front Zone, Antarctica. Deep-Sea Research II, 48 4179 1197. 

Van Oijen T, Van Leeuwe MA, Gieskes WWC (2003) Variation of particulate carbohydrate pools over time and depth in a diatom-dominated plankton community at the Antarctic Polar Front. Polar Biol 26 195-201... 

Landry MR, Hassett RP (1982) Estimating the grazing impact of marine micro-zooplankton. Mar Biol 67 283-288 Landry MR, Selph KE, Brown SL, et al (2002) Seasonal dynamics of phytoplankton in the Antarctic Polar Front region at 170 W Deep Sea Res Part II Top Stud Oceanogr 49 1843-1865... 

Fig. 1 Vertical pattern of Phaeocystis pouchetii export (mg C m 2 d-1) in different water masses in the central Barents Sea (a) Arctic Water, (b) Polar Front and (c) Atlantic water measured by sediment traps at 30, 40,...

Balsfjord 1996, Ullsfjord 1997, Balsfjord, Malangen and Ullsfjord 2001, Barents Sea 1998 and Amundsen Basin, Arctic Ocean 2001 (n = 19) (for further details, see Table 1). A ratio >1 reflects Phaeocystis dominance, while a ratio <1 reflects diatom dominance. Open circles indicate stations were mixing exceeded 90 m at the Barents Sea Polar front and Atlantic water (BS-AW) region in May 1998 (for BS-AW P/D cells C ratio = 43)... 

Antarctic Polar Front" Summer-Dec avg Euphotic zone ww 2.5-9 18.3-29.1 0-6.9 Sambrotto and Mace, 2000... 

Sambrotto, R. N., and Mace, B. J. (2000). Coupling of biological and physical regimes across the Antarctic Polar Front as reflected by nitrogen production and recycling. Deep Sea Res. II 47, 3339-3367. 

The biogeochemical provinces of the Southern Ocean, as defined by Treguer andjacques (1992), are the Polar Front Zone, the Permanently Open Ocean Zone, the Marginal and Seasonal Ice Zones, and the Coastal and Continental Shelf Zone (Fig. 12.1). Note that the Marginal Ice Zone is a seaward subzone of the Seasonal Ice Zone delimited by the recent melting of ice, a seasonally migrating band of recendy exposed surface waters within the Seasonal Ice Zone (Moore et ah, 2000). The... 

Figure 12.1 The sectors of the Southern Ocean and the four biogeochemical provinces the Polar Front Zone, the Permanently Open Ocean Zone, the Marginal and Seasonal Ice Zones, and the Coastal and Continental Shelf Zones.

Front), remained unaltered by Fe additions. In the ACC/Polar Front Zone/Wed-dell Sea regions, modest (0—1.3-fold) increases are reported by van Leeuwe et al. (1997) for specific uptake rates conducted at the beginning of their experi-... 

Figure 12.2 SOFeX depth profiles of biomass (PN)-specific NO/ uptake rates, determined during 24-h incubations in Plexiglas acrylic incubators under simulated in-situ light and temperature conditions. Ultra-clean trace-metal techniques were used for sample collection within and outside (control waters) of the Fe-enriched patch north and south of the Antarctic Polar Front zone. The/-values [f = Fn03/(1 n03 + 1 nH4 + F n02 + F Urea)] were determined at the isolume depths of 47 and 16% surface irradiance, using tracer-level isotopic enrichments, and are not corrected for the effects of isotopic dilution. Error bars represent the range of duplicate samples (n = 2). Corrected from Coale et al. (2004).

Figure 13-9 Schematic views of (A) meridional and vertical transport of nitrate in the upper Atlantic basin and (B) associated horizontal transport pathways. Nitrate-rich Circumpolar Deep Water (CDW) upwells in the Southern Hemisphere and the residual mean flow transports some of this upwelled water across the polar front into the regions of intermediate and mode water formation. Nitrate-rich Sub-Antarctic Mode Water (SAMW) and Antarctic Intermediate Water move northward in the thermocline, ultimately outcropping in the subpolar North Atlantic. Ekman transfer provides a source of nitrate to the subtropical gyre along with lateral and vertical eddy transport processes.

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