Seawater sources temperature

Gong Y, Radachowsky S, Wolf M, Nielsen M, Girguis P, Reimers CE. Benthic microbial fuel cell as direct power source for an acoustic modem and seawater oxygen/temperature sensor system. Environ Sci Technol 2011 45 5047-5053. 

The mineral/salt content of the water is usually measured by the water quality parameter total dissolved solids (TDS), in milligrams per liter (mg/L) or parts per thousand (ppt). Natural water sources such as sea, bay, and ocean waters usually have TDS concentration higher than 15,000 mg/L. Seawater TDS and temperature are the two key source water quality parameters that have the most significant influence on the cost of seawater desalination. Table 3.2 presents typical TDS concentration and temperature for various seawater sources. 

TABLE 3.2 Salinity and Temperature of Various Seawater Sources"... 

Seawater Source Total Dissolved Solids Concentration (mg/L) Temperature (°C)... 

Because seawater signatures of temperature and salinity are acquired by processes occurring at the air-sea interface we can also state that the density characteristics of a parcel of seawater are determined when it is at the sea surface. This density signature is locked into the water when it sinks. The density will be modified by mixing with other parcels of water but if the density signatures of all the end member water masses are known, this mixing can be unraveled and the proportions of the different source waters to a given parcel can be determined. 

At present the Earth s temperature is not in thermal equilibrium, i.e., the net OLR is still not as high as generated net heat. Natural cold sinks in water, ground, and atmosphere slow down the effect of thermal pollution. The main sources of natural cold are in water and ice. The total volume of global water is 1.4 x 1018 m3, of which 94% is seawater while 3 x 1016 m3 (2%) of the water is ice in the form of glaciers and ice fields (Singh and Singh, 2001). 

Figure 5.5. Zeeman profiles of a seawater sample (Sandy Cove N.9) and Sb profiles. The first pair of profiles represents a single 12 xl aliquot, the second pair, two aliquots, and the third pair, three aliquots. The modifier was 200 xg (NH4)2HP04,8% HN03, and 5 ng Mg(N03)2. The char temperature was 550 °C, and the atomisation temperature 1600 °C. Source [135]...

To experimentally validate the Gitterman model, we prepared an artificial seawater sample that had the composition of seawater s liquid partially frozen down to — 23 °C (Marion et al. 1999). To this sample we added an excess of mirabilite crystals to ensure an adequate sulfate source. The sample was then placed in a — 26 °C temperature-controlled bath and allowed to equilibrate with periodic sampling and analyses over a 12-week period. The precipitation of hydrohalite between — 23 °C and — 26 °C (Fig. 3.16) led to an initial decrease in the sodium molality. Magnesium, on the other hand, was conserved in the solution phase, as ice formed and hydrohalite precipi-... 

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