North Atlantic concentrations

An appreciation of the extent to which invertebrate species may be exposed to such chemicals comes from considering the effects of complex mixtures. In the North Atlantic ecosystem alone, hundreds of pollutant chemicals have been identified. These include metals, synthetic and chlorinated organics and polycyclic aromatic hydrocarbons. Over 300 aromatic hydrocarbons have been detected in some regions of the Chesapeake Bay, and high concentrations of PCBs have been... 

Fig. 2-4. Average CO2 concentration North Atlantic Region O, Pacific Region A. (The dashed line is the nineteenth-century base value 290 ppm.) Source Combination of data from Callender, G. C., Tellus, 10, 243 (1958), and Council on Environmental Quality, "Global Energy Futures and the Carbon Ehoxide Problem." Superintendent of Documents, Lf.S. Government Printing Office, Washington, DC, 1981. (See also Fig. 11-1.)...

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

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.)... 

Adkins JF, Boyle EA, Keigwin LD, Cortijo E (1997) Variability of the North Atlantic thermohaline circulation during the last interglacial period. Nature 390 154-156 Anderson RF (1982) Concentration, vertical flux and remineralization of particulate uranium in seawater. Geochim Cosmochim Acta 46 1293-1299... 

For DDE predicted surface ocean concentrations are overestimated in the Gulf of Alaska, the Bering Sea, the Chukchi Sea, and the North Atlantic. In all of these regions also the atmospheric concentration was overestimated. This indicates that the strong overestimation in these regions is caused by enhanced deposition from the atmosphere, and amplified by low volatilisation due to low mean surface temperatures. Also in the East China Sea and in the Gulf of Mexico modelled surface... 

Reported mercury values in the oceans determined since 1971 span three orders of magnitude, due at least in part to errors induced by incorrect sampling [62-64]. Olasfsson [65] has attempted to establish reliable data on mercury concentrations obtained in cruises in North Atlantic water. 

Elderfield and Greaves [629] have described a method for the mass spectromet-ric isotope dilution analysis of rare earth elements in seawater. In this method, the rare earth elements are concentrated from seawater by coprecipitation with ferric hydroxide and separated from other elements and into groups for analysis by anion exchange [630-635] using mixed solvents. Results for synthetic mixtures and standards show that the method is accurate and precise to 1% and blanks are low (e.g., 1() 12 moles La and 10 14 moles Eu). The method has been applied to the determination of nine rare earth elements in a variety of oceanographic samples. Results for North Atlantic Ocean water below the mixed layer are (in 10 12 mol/kg) 13.0 La, 16.8 Ce, 12.8 Nd, 2.67 Sm, 0.644 Eu, 3.41 Gd, 4.78 Dy, 407 Er, and 3.55 Yb, with enrichment of rare earth elements in deep ocean water by a factor of 2 for the light rare earth elements, and a factor of 1.3 for the heavy rare earth elements. 

In general, silver concentrations in surface waters of the United States decreased between 1970-74 and 1975-79, although concentrations increased in the north Atlantic, Southeast, and lower Mississippi basins (USPHS 1990). About 30 to 70% of the silver in surface waters may be ascribed to suspended particles (Smith and Carson 1977), depending on water hardness or salinity. For example, sediments added to solutions containing 2 pg Ag/L had 74.9 mg Ag/kg DW sediment after 24 h in freshwater, 14.2 mg/kg DW at 1.5% salinity and 6.9 mg/kg DW at 2.3% salinity (Sanders and Abbe 1987). Riverine transport of silver to the ocean is considerable suspended materials in the Susquehanna River, Pennsylvania — that contained as much as 25 mg silver/kg — resulted in an estimated transport of 4.5 metric tons of silver to the ocean each year (USEPA 1980). The most recent measurements of silver in rivers, lakes, and estuaries using clean techniques show levels of about 0.01 pg/L for pristine, nonpolluted areas and 0.01 to 0.1 pg/L in urban and industrialized areas (Ratte 1999). 

Concentration profiles from the North Atlantic and North Pacific (a) phosphorus, (b) silicon, (c) iron, (d) nickel, (e) manganese, (f) cadmium, (g) zinc, and (h) copper. Source From Morel, F. M. M., and J. G. Hering (1993) Principles and Applications of Aquatic Chemistry. John Wiley Sons, p. 406. Data sources Bruland, K. W., and R. P. Franks (1983). Trace Metals in Seawater pp. 395-414, C. S., Wong, et al. Plenum Press and Bruland, K. W. (1980). Earth and Planetary Sciences Letters, 47, 176-198. 

The aluminum profile shown in Figure 11.18 is an example of a mid-depth minimmn created by two inputs, one at the surfece and one from the sediments. The high simfece-water concentrations are due to a large atmospheric dust flux in the North Atlantic. As... 

North Atlantic Treaty Organization. Committee on the Challenges of Modem Society. Atmospheric concentrations, pp. 2-1-2-52. In Air Quality Criteria for Photochemical Oxidants and Related Hydrocarbons. N.29. 1974. 

Prospero, J. M and R. T. Nees, Dust Concentration in the Atmosphere of the Equatorial North Atlantic Possible Relationship to the Sahelian Drought, Science, 196, 1196-1198(1977). 

Van Dingenen, R., F. Raes, and N. R. Jensen, Evidence for Anthropogenic Impact on Number Concentration and Sulfate Content of Cloud-Processed Aerosol Particles over the North Atlantic, J. Geophys. Res., 100, 21057-21067 (1995). 

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