North Pacific

M. C. Bek, Fisheries Handbook of Engineering Fequirements and Biological Criteria, U.S. Army Corps of Engineers, North Pacific Division, Portiand, Ore., 1991. 

Although the relationship of sediment adsorption to water concentration appears to be a controlling feature of shallow water systems such as lakes and coastal shelf water, the open ocean is more likely to contain soluble plutonium which seems to be unaffected by particulate matter. This is particularly evident in two oceanographic studies. Bowen et al have discovered a stratum of plutonium in the North Pacific at about 500m that has not changed depth appreciably from 1973 to 1980. How it arrived at this depth is subject to conjecture but it appears to be soluble plutonium which is not settling(17). Fukai et al have delineated plutonium maxima in the Mediterranean Sea which seem to be due to soluble species(18). Comparison of americium to plutonium ratios in this... 

Fig. 1. Major oceanographic features 1. Canary Current, 2. Gulf Stream, 3. North Atlantic Current, 4. Sargasso Sea, 5. North Atlantic Gyre, 6. Labrador Current, 7. Loop Current, 8. North Pacific Gyre, 9. South Equatorial Current, 10. Benguela Current, 11. Humboldt Current, 12. Antilles Current, 13. Florida Current, 14. Brazil Current, 15. Kuroshio, 16. Antarctic West Wind Drift.

Because temperature (T) and salinity (S) are the main factors controlling density, oceanographers use T-S diagrams to describe the features of the different water masses. The average temperature and salinity of the world ocean and various parts of the ocean are given in Fig. 10-3 and Table 10-3. The North Atlantic contains the warmest and saltiest water of the major oceans. The Southern Ocean (the region around Antarctica) is the coldest and the North Pacific has the lowest average salinity. 

As shown in Fig. 10-13, there is also a flux of O2 produced during net photosynthesis from the ocean to the atmosphere and an export flux of particulate and dissolved organic matter out of the euphotic zone. For a steady-state system, new production should equal the flux of O2 to the atmosphere and the export of organic carbon (Eppley and Peterson, 1979) (when all are expressed in the same units, e.g., moles of carbon). Such an ideal state probably rarely exists because the euphotic zone is a dynamic place. Unfortunately, there have been no studies where all three fluxes were measured at the same time. Part of the difficulty is that each flux needs to be integrated over different time scales. The oxygen flux approach has been applied in the subarctic north Pacific (Emerson et al, 1991) and subtropical Pacific (Emerson et al, 1995, 1997) and Atlantic (Jenkins and Goldman, 1985). The organic carbon export approach has... 

Over 20% of the world s open ocean surface waters are replete in light and major nutrients (nitrate, phosphate, and silicate), yet chlorophyll and productivity values remain low. These so-called "high-nitrate low-chlorophyll" or HNLC regimes (Chisholm and Morel, 1991) include the sub-arctic North Pacific (Martin and Fitzwater, 1988 Martin et al, 1989 Miller et al, 1991), the equatorial Pacific (Murray et al, 1994 Fitzwater et al, 1996) and the southern Ocean (Martin et al.,... 

DOC in the deep ocean gradually decreases from 48 /iM in the North Atlantic to 34 /rM in the North Pacific (Hansell and Carlson, 1998). 

Deep ocean concentrations increase progressively as the abyssal water flows (ages) from the North Atlantic, through the Indian Ocean to the North Pacific. 

Karl, D. M., Letelier, R., Hebei, D. et al. (1995). Ecosystem changes in the North Pacific subtropical gyre attributed to the 1991-92 El Nino. Nature 373, 230-234. 

Karl, D., Letelier, R., Tupas, L. et al. (1997). The role of nitrogen fixation in biogeochemical cycling in the subtropical North Pacific Ocean. Nature 388, 533-538. 

Perry, M. J. (1976). Phosphate utilization by an oceanic diatom in phosphorus-limited chemostat culture and in the oligotrophic waters of the central North Pacific. Limnol. Oceanogr. 21,88-107. 

Rue E. L. and Bruland, K. W. (1995). Complexation of iron (111) by natural organic ligands in the Central North Pacific as determined by a new competitive ligand equilibration/adsorptive cathodic stripping voltammetric method. Mar. Chem. 50,117-138. 

Fig. 11-9 (a) The vertical distributions of alkalinity (Aik) and dissolved inorganic carbon (DIC) in the world oceans. Ocean regions shown are the North Atlantic (NA), South Atlantic (SA), Antarctic (AA), South Indian (SI), North Indian (NI), South Pacific (SP), and North Pacific (NP) oceans. (Modified with permission from T. Takahashi et ah, The alkalinity and total carbon dioxide concentration in the world oceans, in B. Bolin (1981). Carbon Cycle Modelling," pp. 276-277, John Wiley, Chichester.)... 

Nakazawa, T., Murayama, S., Miyashita, K., Aoki, S. and Tanaka, M. (1992). Longitudinally different variations of lower tropospheric carbon dioxide concentrations over the North Pacific Ocean, Tellus, Ser. B, 44,161-172. 

Karl, D. M. and Yanagi, K. (1997). Partial characterization of the dissolved organic phosphorus pool in the oligotrophic North Pacific Ocean. Limnol. Oceanogr. 42,1398-1405. 

Smith, S. V., Kimmerer, W. J., and Walsh, T. W. (1986). Vertical flux and biogeochemical turnover regulate nutrient limitation of net organic production in the North Pacific Gyre. Limnol. Oceanogr. 31, 161-167. 

Settle, D. M. and Patterson, C. C. (1982). Magnetites and sources of precipitation and dry deposition fluxes of industrial and natural leads to the North Pacific at Enewetak. /. Geophys. Res. 87, 8857-8869. 

Burger J, Shukla T, Dixon C, Shukla S, McMahon MJ, Ramos R, Gochfeld M. 2001. Metals in feathers of sooty tern, white tern, gray-backed tern, and brown noddy from islands in the North Pacific. Environ Monit Assess 71 71-89. 

Douglas, G. and Savin, S.M. (1973) Oxygen and carbon isotope analyses of Cretaceous and Tertiary foraminifera from the central North Pacific. Washington, D.C. U.S. Govt. Printing Office, Initial Reports of the Deep Sea Drilling Project, 17, 591-605. 

Benitez-Nelson C, Buesseler KO, Karl D, Andrews J (2001b) A time-series study of particulate matter export in the North Pacific Subtropical Gyre based upon " Th U disequilibrium. Deep-Sea Res I 48 2595-2611... 

Nozaki Y, Tsunogai S (1976) Ra-226, Pb-210 and Po-210 disequilibria in western North-Pacific. Earth Planet Sci Lett 32 (2) 313-321... 

Nozaki Y, Horibe Y, Tsubota H (1981) The water column distributions of thorium isotopes in the western North Pacific. Earth Planet Sci Lett 54 (2) 203-216... 

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