Pacific Ocean, salinity, temperature

Deep Ocean— The deep ocean environment is very different from the ocean at the surface. At sites in the North Atlantic and North Pacific Oceans, oxygen, temperature, and salinity vary with depth. At the ocean surface, the oxygen concentration in the North Pacific is 1.4 times the oxygen content in the North Atlantic. In addition, both the surface temperature and surface salinity are lower in the North Pacific than in the North Atlantic. Below about 1500 m, however, temperature and salinity levels are approximately the same at these two ocean sites [1,6. ... 

Variability of Seawater Vertical sections through seawater showing the distribution of temperature, salinity, and oxygen for the Pacific Ocean and Western Atlantic Ocean are shown in Figures 21.3 and 21.4. The global variability of natural seawater and its effects on corrosion have been reviewed in particular with respect to seasonal variation of temperature, salinity, oxygen and pH in the Pacific surface water. Data is also given on... 

Fig. 21.3 Vertical sections showing distribution of temperature, salinity, and oxygen in the Pacific Ocean, approximately along the meridian of I70°W. (After Sverdrup, H. U., Oceanography for Meteorologists, Allen and Unwin (1945))...

Fig. 10-4 Average temperature/salinity diagrams for Pacific Oceans. (Reproduced with permission from G. L. Oceanography," pp. 138-139, Pergamon Press.)...

Vertical concentration profiles of (a) temperature, (b) potential density, (c) salinity, (d) O2, (e) % saturation of O2, (f) bicarbonate and TDIC, (g) carbonate alkalinity and total alkalinity, (h) pH, (i) carbonate, ( ) carbon dioxide and carbonic acid concentrations, and (k) carbonate-to-bicarbonate ion concentration ratio. Curves labeled f,p have been corrected for the effects of in-situ temperature and pressure on equilibrium speciation. Curves labeled t, 1 atm have been corrected for the in-situ temperature effect, but not for that caused by pressure. Data from 50°27.5 N, 176°13.8 W in the North Pacific Ocean on June 1966. Source From Culberson, C., and R. M. Pytkowicz (1968). Limnology and Oceanography, 13, 403-417. 

Reid J. L. (1969) Sea surface temperature, salinity, and density of the Pacific Ocean in summer and in winter. Deep-Sea Res. 116(suppL), 215-224. 

A useful apphcation of preformed nutrient concentrations is that they are intrinsic to different water masses and sometimes can be used as conservative tracers. For example, the main sources of deep water in the Pacific Ocean are North Atlantic Deep Water (NADW), Antarctic Intermediate Water (AAIW) and Antarctic Bottom Water (AABW), all of which are at least partly homogenized in the Antarctic Circumpolar Water (AACW). It is not possible to determine how much of each of these sources contributes to Pacific deep water by using end member mixing of the conservative properties temperature and salinity because salinities of the end members are not sufficiently different. Since concentrations of DIP are well above detection limits in... 

Fig. 9-5 Average temperature/salinity diagrams for the main water masses of the Atlantic, Indian, and Pacific Oceans. Reproduced from Pickard and Emery (1982) with the permission of Pergamon Press.

Superimposed on the general depth-dependent decrease of carbonate accumulation observed everywhere in the deep sea are preservation patterns that differ between the major ocean basins. Today, carbonate-rich sediments tend to accumulate in the Atlantic Ocean, while more carbonate-poor sediments are generally found at comparable water depths in the Indian and Pacific Oceans. This modern pattern is largely the product of the ocean s thermohaline circulation and has been termed basin-to-basin fractionation . In the Atlantic, deep and bottom waters tend to be produced at high latitudes because cold temperatures and high sea surface salinities lead to the formation of dense water... 

Fig. 21.3 Distribution of temperature, salinity and oxygen in the Pacific Ocean...

Circulation in the Columbia River estuary is primarily driven by tides, river discharges, and salinity- and temperature-induced density differences between freshwater and ocean water. In addition, wind and Eastern North Pacific Ocean currents are important factors in the dynamics of the Columbia River plume, and ocean-water heat exchange regulates temperatures inlateralbays in the estuary and at ocean scales. Arguably, current-wave interaction is also a significant factor at the entrance of the estuary. 

Figure 2.23 Variations in seawater with depth at a Pacific Ocean test site. The units have to be estimated with the following conversion temperature, scale X 1 (°C) oxygen, scale X 0.333 (ppm) pH, 6.4 + scale X 0.1 (pH unit) salinity, 33.0 + scale X 0.1 %o).

Certain physicochemical characteristics of seawater such as salinity, temperature and oxygen concentration vary as a function of the immersion depth. This has been shown by measurements taken in the Pacific Ocean off California between the surface and a depth of 2000 m (Figure D.3.1). 

Because temperature (T) and salinity (S) are the main factors controlling density, oceanographers use T-S diagrams to describe the features of the different water masses. The average temperature and salinity of the world ocean and various parts of the ocean are given in Fig. 10-3 and Table 10-3. The North Atlantic contains the warmest and saltiest water of the major oceans. The Southern Ocean (the region around Antarctica) is the coldest and the North Pacific has the lowest average salinity. 

Fig. 9. Dissolved inorganic carbon, salinity, phosphate, nitrate, and temperature in surface ocean waters, during the 1982-83 El Nino, at the same longitude as in Fig. 7. Note that the high values for CO2 and nutrients south from the equator have disappeared while the water temperature has become warmer as warm waters from the Western Pacific flooded over the region. Measurements by C. D. Keeling, R. F. Weiss and others.

Latitudinal cross section of the potential temperature and salinity of the Atlantic (A) and Pacific (B) oceans. Different water masses are definable by their characteristic temperature and salinity (Table 1.3). (Plotted by using Ocean Data View and WOCE hydrographic data (Schlitzer, 2001).)... 

Figure 1. Maps of mixed layer depth in the global ocean as monthly averages for January (upper panel) and July (middle panel). The lower panel shows typical profiles of sigma-t (a measure of density) for a polar (Southern Ocean) versus tropical (Pacific) area of the ocean. The maps use global ocean temperature and salinity data sets compiled by the U.S. National Oceanic Atmospheric Administration as processed by Kara et al. [94].

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