Water Mediterranean

Conventional T-S diagrams for specific locations in the individual oceans are shown in Fig. 10-4. The inflections in the curves reflect the inputs of water from different sources. The linear regions represent mixing intervals between these core sources. For example, in the Atlantic Ocean the curves reflect input from Antarctic Bottom Water (AABW), North Atlantic Deep Water (NADW), Antarctic Intermediate Water (AIW), Mediterranean Water (MW), and Warm Surface Water (WSW). 

To determine whether his Pacific samples were in fact representative of other oceans, Patterson and a Japanese colleague, Mitsunobu Tat-sumoto, began developing profiles of the lead in ocean layers in Atlantic and Mediterranean waters. Patterson hated ocean-going field trips he often became violently seasick, once so seriously that he had to be given oxygen. Because the ships were coated with leaded paints and compounds, sampling was tricky, too. Despite the problems, Patterson could see that, as in the Pacific, lead was concentrated in the upper portions of the Atlantic and Mediterranean. 

M. Tatsumoto and C. C. Patterson. Concentrations of Common Lead in Some Atlantic and Mediterranean Waters and in Snow. Nature. 199 (July 27, 1963) 350-352. Source for extrapolation from sea surface to leaded gasolines and Lassen National Park. 

Focardi, S., C. Leonzio, and C. Fossi. 1988b. Variations in polychlorinated biphenyl congener composition in eggs of Mediterranean water birds in relation to their position in the food chain. Environ. Pollut. 52 243-255. 

Acinas, S. G., J. Anton, and F. Rodriguez-Valera. 1999. Diversity of free-living and attached bacteria in offshore western Mediterranean waters as depicted by analysis of genes encoding 16S rRNA. Applied and Environmental Microbiology 65 514—522. 

Temperature affects food supply in another way also. The Mediterranean sprat, which prefers cold waters, exploits a wider feeding area than fish that inhabit only warm waters, because it takes advantage of a greater water depth and can feed all the year round. It possesses a much greater lipid reserve than the warm-water anchovy, and its range of fatness over the annual cycle is wider (Figure 36). The feeding conditions in the warm Mediterranean waters are therefore more favourable to fish that prefer cooler waters rather than warm. 

Meinesz, A., de Vaugelas, J., Hesse, B., and Mari, X., Spread of the introduced tropical green alga Caulerpa taxifolia in northern Mediterranean waters, J. Appl. Phycol., 5, 141, 1993. 

Simo, R., Grimalt, J.O., and Albaiges, J. (1997) Dissolved dimethylsulfide, dimethyl-sulphonioproprionate and dimethyl-sulphoxide in western Mediterranean waters. Deep-Sea Res. II, 44, 929-950. 

Wahby, S,D., and Bishara, N.F. (1979) The effect of the river Nile on Mediterranean water, before and after the construction of the High Dam at Aswan. In River Inputs to Ocean Systems (Martin, J.M., Burton, J.D., and Eisma, D., eds.), pp. 311-318, U.N. Environ. Prog. Intergov. Oceanogr. Comm. Sci. Comm. Ocean. Res., Rome. 

Fig. 2 Development of anoxic conditions in the Black Sea water column over time, based on modeling results. Solid and dashed lines represent vertical profiles of dissolved oxygen and hydrogen sulfide, respectively. Numbers are x 1000 years since the first appearance of the Mediterranean waters in the Black Sea. Filled circles and horizontal bars represent the average and the range of the observed concentrations in the present Black Sea,...

The average isotope compositions of the sulfate sulfur in the oxic and anoxic zones are + 18.5%o and + 19.5%, respectively. The isotopic composition of sulfate in the Black Sea forms from two distinct sources. The sea receives annually about 2.82 x 106 tons of sulfate with river discharge with the average isotope composition of + 4.6% [71]. The annual input with Mediterranean waters of 540 x 106 tons of sulfates has an isotopic composition of about + 19.8%o [18]. The isotopic composition of dissolved sulfide averaged over all depths is - 39.6 1.3%o and varies between - 42.0%o and - 32.6%o for all stations [65] (Fig. 5). There is no indication that the sulfur isotopic composition of hydrogen sulfide changes spatially and/or seasonally. 

The sulfur budget for the Black Sea has been considered in several papers [23, 24,74-77]. Sulfide sources are sulfide production in sediments, sulfide flux at the sediment/water interface, and sulfide production in the water column. Sulfide sinks are sulfide oxidation at the oxic/anoxic interface and in the basin interior by dissolved oxygen of the modified Mediterranean water and iron sulfide formation in the water column. 

Fig. 7 Sulfur budget for the Black Sea anoxic zone. The width of arrows and dimension of ovals represent the relative magnitudes of respective processes. SMMW stands for shelf modified Mediterranean water. Processes rates are in 1012 gSyear 1 (modified from [75])...

The analysis of Atlantic waters may be regarded as typical of large oceans. The Mediterranean waters are more concentrated,2 partly because of the high rate of evaporation, and partly because few rivers flow into it. Even more concentrated are the waters of the Red Sea,3 for similar reasons. 

Tatsumoto M. T. and Patterson C. C. (1963) The concentration of common lead in some Atlantic and Mediterranean waters and in snow. Nature 199, 350-352. 

AABW, Antarctic Bottom Water NADW, North Atlantic Deep Water MW, Mediterranean Water AAIW, Antarctic Intermediate Water T and S characteristics from Picard and Emery (1982) How rates are in Sverdrups (10 m s ). 

Subsurface eddies are formed also by Mediterranean water flowing around topographic feauires with a small radius of curvature at the shelf off Spain and Portugal. These eddies are denoted as Mediterranean eddies (Meddles). 

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. 3.2 (a) Simplified, schematic representation of oceanic deep water circulation (after Broecker 1997). (b) Water masses in theAtlantic (after Stowe 1979). AABW =Antarctic Bottom Water AAIW =Antarctic Intermediate Water AIW = Atlantic Intermediate Water med = Mediterranean Water NADW = North Atlantic DeepWater. 

Oren, A. (1970) Seasonal changes in the physical and chemical characteristics and the production in the low trophic level of the Mediterranean waters off Israel. PhD thesis, Hebrew University Jerusalem, 238 pp. 

Vaulot, D., LeBot, N., Marie, D. and Fukai, E. (1996) Effect of phosphorus on the Synechococcus cell cycle in surface Mediterranean waters during summer. Applied Environmental Microbiology, 62, 2527-2533. 

Fig. 2. Dimethyl sulphide profiles (A) in Mediterranean waters and the respective density (B) distribution. (After Nguyen et al., 1978.)...

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