Pacific Ocean effect

Pacific Ocean effect into a San Francisco Bay effect — an imperfect barrier that minimizes leakage of protons into the bulk solutions. Such a speculated barrier was realized by the discovery of Teissie and coworkers. > These investigators found that proton conduction is considerably faster on the membrane-water interface than in the bulk water. Subsequently, Alexiev et aL found similar proton conduction on the surface of the purple membrane of Halobacterium salinarum. 

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... 

Comparison with other Studies. How do the results of our investigation compare with similar studies Our results corroborate the data provided in a similar study of the effect of UV-B on primary productivity in the southeastern Pacific Ocean (35). In the latter study, it was noted that enhanced UV-B radiation caused significant decreases in the productivity of surface and deep samples. Compared to ambient, primary productivity decreased with increasing doses of UV-B. In another study in which in situ experiments using natural Antarctic phytoplankton populations, it was noted that incident solar radiation significantly depressed photosynthetic rates in the upper 10-15 meters of the water column (36). It was also found that the spectral region between 305 and 350 nm was responsible for approximately 75 percent of the overall inhibitory effect. 

Fig. 9-4 Photograph of landslides (soil avalanches) that occurred following earthquakes in Panama on July 17,1976, near Jaque. In the background is a bay of the Pacific Ocean. The effects of this earthquake are described by Garwood et al. (1979), who estimated that about 42 km (about 10%) of the region near the epicenter of the earthquake was devegetated. The bedrock is mostly island-arc basalts and andesites. (Photography by N. C. Garwood.)...

This simple two component model for the Fe isotope composition of seawater does not consider the effects of the Fe isotope composition of dissolved Fe from rivers or from rain. Although the dissolved Fe fluxes are small (Fig. 19) the dissolved fluxes may have an important control on the overall Fe isotope composition of the oceans if they represent an Fe source that is preferentially added to the hydrogenous Fe budget that is ultimately sequestered into Fe-Mn nodules. In particular riverine components may be very important in the Pacific Ocean where a significant amount of Fe to the oceans can be delivered from rivers that drain oceanic islands (Sholkovitz et al. 1999). An additional uncertainty lies in how Fe from particulate matter is utilized in seawater. For example, does the solubilization of Fe from aerosol particles result in a significant Fe isotope fractionation, and does Fe speciation lead to Fe isotope fractionation ... 

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. 

The distribution of sediment types in the Pacific Ocean is much different from that of the Atlantic. Except for the coastline of the northwest United States, the Pacific is ringed by deep-sea trenches and, hence, has relatively narrow continental shelves. The trenches effectively trap all the terrigenous particles carried to the sea by river runoff. The Pacific Ocean is much wider than the other oceans thus the flux of wind-borne lithogenous particles is spread over a much greater area and produces a much lower mass flux, on an areal basis, to the seafloor. This makes other particles relatively important in determining the composition of the sediments in the Pacific ocean. 

FIGURE 14.50 Schematic of energy balance in warm pool in western Pacific Ocean used to deduce the net effect of clouds on solar radiation. All numbers are given in W m2 (adapted from Ramanathan et at., 1995). 

Valero, F. P. J., W. D. Collins, P. Pilewskie, A. Bucholtz, and P. J. Flatau, Direct Radiometric Observations of the Water Vapor Greenhouse Effect over the Equatorial Pacific Ocean, Science, 275, 1773-1776 (1997b). 

Climate researchers Palutikof and Holt (2004) say that droughts appear to be linked to the formation of blocking zones of intense high pressure over the Atlantic Ocean that divert rain-bearing wind depressions away from the Mediterranean. This blocking may be related to the cycles of El Nino, the periodic reversal of winds and waves in the tropical Pacific Ocean. Due to the effects of toxic gases, it is assumed that year-round average temperature in southern Europe will reach 18°C by the year 2030 and rainfall will diminish by 19% to 20%. 

For example, a 3 per cent, solution of common salt at 10° C. is much more corrosive than tap water at the same temperature but as the temperature rises the relative corrosivity falls, so much so that at 21° C. the salt solution is the 1 ess corrosive of the two. Since sea water contains some 3 per cent, of sodium chloride, it is of interest to inquire into the effect of temperature upon its corrosive powers. The few laboratory tests that have been carried out on the subject2 indicate that at temperatures below 13° C. sea water is more corrosive than tap water, whilst at all higher temperatures it is less so. Now, in the western part of the tropical Pacific Ocean a temperature of 32° C. is sometimes attained, and in the Red Sea and Persian Gulf temperatures of 34 4° C. and 35 5° C. respectively have been registered. Such waters should therefore prove less corrosive than river waters at the same temperatures. 

Field studies continue to support the conclusion of Dortch (1990), that the effect of NH4+ on NOs uptake is highly variable. For example, NOs uptake rates in natural assemblages dominated by the coccolithophorid Emiliania huxleyi from the subarctic NE Pacific Ocean were reduced by 50% at NH4 concentrations of 0.24 pM with nearly complete inhibition at 2.2 pM (Varela and Harrison, 1999a). Based on the average ambient NH4 concentrations during these blooms, this translates into a 38—70% reduction in NOs uptake rates, the majority of which occurred... 

A similar reduction in the inhibitory effects of NH on NOj uptake rate was determined during the second Subarctic Pacific Iron Experiment for Ecosystem Dynamics Study (SEEDS-11) conducted in July-August 2004 in the western subarctic Pacific Ocean (Cochlan et al, 2005), despite a relatively modest increase in phytoplankton biomass following Fe enrichment. 

Prospero, J. M., and Savoie, D. L. (1989). Effect of continental sources on nitrate concentrations over the Pacific Ocean. Nature 339, 687—689. 

Testing the iron hypothesis in ecosystems of the equatorial Pacific Ocean. Nature 371, 123—126. Mayer, M. S., Schaffner, L., and Kemp, W. M. (1995). Nitrification potentials of benthic macrofaunal tubes and burrow walls Effects of sediment NH4" and animal irrigation behavior. Mar. Ecol. Prog. Ser. 121, 157-169. 

NMR spectroscopy has proven to be the most effective technique for characterizing carbon functional groups in HMW DOM. The i C-NMR spectrum of HMW DOM collected at 15 m in the North Pacific Ocean surface is given in Figure 6(a). Nearly identical spectra have been collected from the Atlantic Ocean, as well as from some lakes and rivers (McKnight et al., 1997 Repeta et al., 2002). All C-NMR spectra display a rather simple pattern of broad resonance from carboxyl (CO-(OH or NH) 175 ppm), alkene/ aromatic (C=C 140 ppm), anomeric (O-C-O 100 ppm), alcoholic (H-C-OH 70 ppm), and... 

---