Ocean Mediterranean

Lithology Arctic Ocean Atlantic Ocean Indian Ocean Pacific Ocean Mediterranean + Black Sea Endorheic (Internal) Global... 

Volcanic sources of the free element are also widespread they have been of great economic importance until thi.s century but are now little used. They occur throughout the mountain ranges bordering the Pacific Ocean, and also in Iceland and the Mediterranean region, notably in T irkey, Italy and formerly also in Sicily and Spain. 

Local conditions may modify this profoundly in special areas. In the Arctic and Antarctic, and where there is dilution by large rivers, the salinity may be considerably less, and it may vary greatly according to season. Salinity is well below normal in the Baltic, and may fall nearly to zero at the head of the Gulf of Bothnia. In enclosed seas like the Mediterranean, Black Sea and Red Sea, on the other hand, where there is rapid evaporation, salinity may reach 40 parts per thousand. The total salt content of the inland Dead Sea is 260 g/kg compared to 37 g/kg for the Atlantic Ocean. 

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... 

A circumnavigation of the world s oceans between 1978-1980 (18), further indicated that broad expanses of the Atlantic, Pacific, and Indian Oceans away from major tanker lanes and shipping routes contained little or no tar, whereas tar pollution was prevalent in the Mediterranean, Java Sea and Red Sea, and in western European and Northwest African coastal areas. 

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). 

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). 

Evaporite deposition is a much more episodic process and thus difficult to quantify. Because seawater is significantly undersaturated with respect to common evaporitic minerals, like gypsum and halite, evaporites are only formed when restricted circulation develops in an ocean basin in which evaporation exceeds precipitation. A geologically recent example is the Mediterranean Sea of 5-6 Myr ago. At this time excess evaporation exceeded the supply of ocean water through shallow inlet(s) from the Atlantic Ocean. As salinity increased, first CaS04, then NaCl precipitated. Over time, salt deposits 2-3 km thick formed. This thickness represents about 40 desiccations of the entire... 

Ocean prevents eutrophication. Much more water flows into the Mediterranean Sea than is required to replace evaporation from it. The excess, high salinity water exits Gibraltar below the water flowing in af fhe surface. Nufrients that enter the Mediterranean Sea from pollution sources are utilized by marine phytoplankton that sinks and exits with the outflow. Another example is that estuaries often have lower salinity or even freshwater at the surface with a denser saline layer at the bottom. An estuarine circulation occurs with nutrients being trapped in the saline bottom water. 

Among the 14 PCB congeners found at die highest concentration in eggs from die Mediterranean Sea and die Atlantic Ocean (Renzoni et al. 1986). These audiors also found numbers 156, 172, and 183. Numbers 172 and 183 were also reported in Borlakoglu et al. (1988). 

Heussner S, Cherry RD, Heyraud M (1990) Po-210 and Pb-210 in sediment trap particles on a Mediterranean continental margin. Cont. Shelf Res 10 989-100 Heyraud M, Cherry RD (1983) Correlation of Po-210 and Pb-210 enrichments in the sea-surface microlayer with neuston biomass. Cont Shelf Res 1 283-293 Honeyman BD, Santschi PH (1989)The role of particles and colloids in the transport of radionuclides and trace metals in the oceans. In Environmental particles. Buffle J, van Leewen HP (eds) Lewis Publishers, Boca Raton, p 379-423... 

Kharkar DP, Thomson J, Turekian KK, Forster WO (1976) Uranium and thorium series nuclides in plankton from the Caribbean. Limnol Oceanogr 21 294-299 Krishnaswami S, Lai D, Somayajulu BLK, Weiss R, Craig H (1976) Large-volume in situ filtration of deep Pacific waters mineralogical and radioisotope studies. Earth Planet Sci Lett 32 420-429 Livingston HD, Cochran JK (1987) Determination of transuranic and thorium isotopes in ocean water in solution and in filterable particles. J Radioanal Nucl Chem 115 299-308 Masque P, Sanchez-Cabeza JA, Braach JM, Palacios E, Canals M (2002) Balance and residence times of °Pb and 4 o in surface waters of the northwestern Mediterranean Sea. Cont Shelf Res 22 2127-2146 Matsumoto E (1975) Th-234-U-238 radioactive disequilibrium in the surface layer of the oceans. Geochim Cosmochim Acta 39 205-212... 

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. 

The oceanic burden in December 2004 shows the contamination of the ocean after 50 years of PFOA emissions (Figure 3.14). Highest PFOA burden is located in the northern Atlantic, Mediterranean, and the Arctic ocean. Contaminations of the Atlantic, Mediterranean and Pacific can be related to the vicinity to the oceanic source. PFOA in remote regions, however, such as in the Arctic must have been transported via atmosphere or ocean. MPI-MTCM does not simulate degradation of PFOA from volatile, highly mobile precursor substances, that contribute to the ocean burden in the Arctic by deposition. Then annual dry and wet deposition rates of PFOA in the model are small compared to the mass emitted directly to the ocean. This implies that the burden in the Arctic is results mainly from oceanic long-range transport. 

Statham C, Murray CN (1976) Report of the International Committee of the Mediterranean Ocean 23 163... 

The topography of the Ebro River basin determines a Mediterranean climate with continental characteristics in most of the river basin as well as a semi-arid climate in the center of the depression. At the western extreme of the basin (Pyrenees and Iberian mountains), there is an oceanic climate. The central part of the basin is isolated from the oceanic influence because of the surrounding mountains. This results in the increase of the continentality of the climate and the drastic decrease of the rainfall. In the central part of the river basin (Zaragoza, Alcaniz, and Lleida urban areas), aridity is the main climatic characteristic. 

During this time, global cooling led to an intense ice age that caused sea level to drop below the level of the Gibraltar Sill, isolating the Mediterranean Sea from the Atlantic Ocean. Arid conditions promoted evaporation, transforming the Mediterranean into a series of large inland lakes. As these lakes dried up, an enormous volume (1 x lo km ) of evaporites was deposited. 

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