Atlantic, opening

Figure 13-13 Nitrogen budget for the North Atlantic, modified from Galloway et al. (1996), demonstrating the m or fluxes (xlO mol year ) across the boundaries of the hasin as well as sinks (denitrification) and new sources (nitrogen fixation nitrogen deposition (N dep.)) of reactive N. Fluxes into the m or physical realms of the North Atlantic (open ocean, shelf waters, and estuaries) are highlighted hy diagonal-line fills loss terms and exchange fluxes between realms are indicated by open arrows.

Figure 4 Depth profiles of (A) dissolved gallium in the central North Pacific (solid symbols 28°N 155°W Orians and Bruland, 1988) and in the western North Atlantic (open symbols 32°N 64°W Shiller, 1998), and (B) dissolved indium in the western North Pacific (solid symbols 34°N 142°E Amakawa eta ., 1996) and in the eastern North Atlantic (open symbols 26° N, 37°W Alibo etat., 1999).

Figure 6 Depth profiles of (A) zirconium, (B) hafnium, and (C) the Zr/Hf atom ratio, in the North Pacific (solid symbols 50°N 145°W McKelvey and Orians, 1998) and in the North Atlantic (open symbols 48°N 15°W Godfrey et a ., 1996).

Figure 8 Depth profiles of dissolved Iron In (A) the North Pacific (solid symbols 50°N 145°W Martin et ai, 1989) and the North Atlantic (open symbols 47°N 20°W Martin et al., 1993), and (B) the central North Pacific (28°N, 155°W Bruland eta ., 1994).

Recent data and an assessment (1993-94) of the flux of PCBs to the North Atlantic open ocean have estimated, as an example, that 14 000 mol year of a tetrachlorobiphenyl congener was sequestered in the north-western Atlantic Ocean with 75% of the flux... 

Wave size is determined by wind speed and fetch, the distance over the oceans surface which the wind travels. Favorable wind energy sites are generally western coastlines facing the open ocean such as the Pacific Coast of North America and the Atlantic Coast of Northern Europe. Norway, Denmark, Japan, and the United Kingdom are the world leaders in wave energy technologies. 

There were many examples of early interconnected electric transmission systems extending across state territories and beyond state boundaries. Statements from a speech by Samuel Insull at Purdue University in 1924 indicated that Minneapolis, St. Paul, St. Louis, Louisville, and Cincinnati soon would be interconnected and that extension of these systems to Pittsburgh and across the Allegheny Mountains to the Atlantic Seaboard could be easily conceivable in a few years. This was but one example across the United States. To quote Insull, It makes electric service available in new places for new pui poses, so that aggregate demand for service is spread over more hours of day and night, and thus opens the way to utmost economy in production and distribution. ... 

Over the past decade, plastic debris has become a common feature of beaches and coastal waters adjoining populated areas of Europe (36-38), the Mediterranean (39-41), North and Central America (42-44) and New Zealand (45). Plastics are also present in the open ocean both near the major shipping lanes and in the most remote regions of the world (the Arctic (46), the Benguela Current (47), the Cape Basin area of the South Atlantic (48), the Humboldt Current in the South Pacific (49), and the Antarctic (50, 51). 

The concentration of trichloroethylene in the open oceans may be an indication of the environmental background levels in water. Levels in open waters of the Gulf of Mexico were below the detection level of 1 ppt (Sauer 1981). Average levels of 7 ng/L (7 ppt) and 0.3 ppt were found in the northeastern Atlantic (Murray and Riley 1973) and in Liverpool Bay (Pearson and McConnell 1975), respectively. 

Fig. 2.39. Na /K+ atomic ratios of well discharges plotted at measured downhole temperatures. Curve A is the least squares fit of the data points above 80°C. Curve B is another emperical curve (from Truesdell, 1976). Curves C and D show the approximate locations of the low albite-microcline and high albite-sanidine lines derived from thermodynamic data (from Fournier, 1981). Small solid subaerial geothermal water Solid square Okinawa Jade Open square South Mariana Through Solid circle East Pacific Rise 11°N Open circle Mid Atlantic Ridge, TAG.

Fitzgerald et al. [477 ] showed that the most significant quantities of mercury occurred in the waters of the Atlantic Ocean s continental shelf and slope (21 -78 ng/1), compared with open ocean samples (2 -11 ng/1). 

Figure 16. Depth profiles from three ODP Sites, showing Li isotopic composition variations in pore waters (open symbols) and associated sediments (filled symbols), (a) Site 918, Irminger Basin, north Atlantic (Zhang et al. 1998) (b) Site 1038, Escanaba Trough, northeastern Pacific (James et al. 1999) (c) site 1039, Middle American Trench off of Costa Rica (Chan and Kastner 2000). The average composition of seawater is noted on each profile with dashed line (note different scales). Whereas sediments have relatively monotonous compositions, pore waters have compositions reflecting different origins and processes in each site. Interpretations of the data are summarized in the text under, Marine pore fluid-mineral processes. ...

Vapor and brine from the Brandon vent of the East Pacific Rise have identical Fe isotope compositions, implying that phase separation does not produce an isotopic fractionation (Beard et al. 2003a). The role that sulfide precipitation plays in controlling the Fe isotope composition of the fluid remains unknown. The precision of the two sulfide analyses reported by Sharma et al. (2001) was not sufficient to resolve if sulfide precipitation would produce Fe isotope fractionation in the vent fluid. In a detailed study of sulfldes from the Lucky Strike hydrothermal field from the mid Atlantic Ridge, however, Rouxel et al. (2004) found that sulfldes span a range in 5 Fe values from -2.0 to +0.2%o, and that pyrite/marcasite has lower 5 Fe values ( l%o) as compared to chalcopyrite. The variations in mineralogy and isotope composition are inferred to represent open-system equilibrium fractionation of Fe whereby... 

Natural production was speculated to be the source of 1,2-dibromoethane found in ambient air samples collected from open areas of the North and South Atlantic Ocean by Class and Ballschmitter (1988) concentration levels were reported to be less than 0.001-0.003 ppt. 

The sediment oxygen penetration depth as a function of water coiumn depth in the Atlantic Ocean (open symbols) and Pacific Ocean (closed symbols). Source-. From Martin, W. R., and F. L. Sayles (2003). Treatise on Geochemistry, Elsevier. 

I860 and the mid-1990s, areal deposition rates in the coastal waters increased by more than a fector of 10 and in open ocean regions by at least a factor of 2, particularly in the North Atlantic. The aeolian deposition pattern now reflects transport via the Westerlies from North America to Europe and via the Trade Winds from Africa to South America. 

Schmidt, D., and W. Gerwinski, (1992). A baseline study for trace metals in the open Atlantic Ocean. International Council for the Exploration of the Sea. ICES CM 1992/E18, 15pp. 

A new era of European supremacy will open up in the domain of nuclear gamma astronomy, for no large-scale project has been proposed across the Atlantic to take up where the CGRO observatory left off. Let us hope that European science will make the most of this boon. ... 

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