Ocean surface range

Many hydrologic reservoirs can be further subdivided into smaller reservoirs, each with a characteristic turnover time. For example, water resides in the Pacific Ocean longer than in the Atlantic, and the oceans surface waters cycle much more quickly than the deep ocean. Similarly, groundwater near the surface is much more active than deep reservoirs, which may cycle over thousands or millions of years, and water frozen in the soil as permafrost. Typical range in turnover times for hydrospheric reservoirs on a hillslope scale (10-10 m) are shown in Table 6-4 (estimates from Falkenmark and Chapman, 1989). Depths are estimated as typical volume averaged over the watershed area. 

Fig. 10-15 Organic carbon fluxes with depth in the water column normalized to mean annual primary production rates at the sites of sediment trap deployment. The undulating line indicates the base of the euphotic zone the horizontal error bars reflect variations in mean annual productivity as well as replicate flux measurements during the same season or over several seasons vertical error bars are depth ranges of several sediment trap deployments and uncertainities in the exact depth location. (Reproduced with permission from E. Suess (1980). Particulate organic carbon flux in the oceans - surface productivity and oxygen utilization, Nature 288 260-263, Macmillan Magazines.)...

Fig. 11-24 Carbon-14 in the troposphere and the ocean surface water 1962-1981. values for ocean surface water during this period range from 0-15% with no trend over time. (Modified with permission from R. Nydal and K. Lovseth (1983). Tracing bomb in the atmosphere. /. Geophys. Res. 88, 3621-3642, American Geophysical Union.)...

The predicted pH is 8.34, a value lying within but toward the alkaline end of the range 7.8 to 8.5 observed in seawater (Fig. 6.1). The dissolved oxygen content predicted by the calculation is 215 qrnol kg-1, or 6.6 mg kg-1. This value compares well with values measured near the ocean surface (Fig. 6.2). 

Table E8.7.1 Transfer enhancement ratio for a range of liquid film coefficients common on the ocean surface...

Because the mean pH of the today s ocean surface layer is about 8.08 (with a range from 7.9-8.25) (Raven et al, 2005), oceanic NH3 can exist as a dissolved, non-protonated gas and, thus, it is available for gas exchange across the ocean/ atmosphere interface. For example, for a pH of 8.1, a water temperature of 25°C, and a salinity of 35, about 6% is available as dissolved NH3, [NH3], (Fig. 2.8). The NH3/NH4 equilibrium is very sensitive to changes of the pH and water temperature. Changes in salinity and pressure are comparably less important (Fig. 2.8). 

Iron is the only nutrient element for which particulate concentrations are typically higher than dissolved levels (de Baar and de Jong, 2001). Despite this, considerably more research attention has focused on measuring dissolved pools than on the particulate fraction. The literature on total dissolved Fe concentrations is now far too extensive to comprehensively review here, but most analysts report oceanic surface concentrations of <0.1—0.5 nM (de Baar and de Jong, 2001 Johnson et al., 1997), and deep-water levels ranging from 0.3 to 0.7 nM (Parekh etal., 2005). Some differences in reported dissolved Fe levels could be due to analytical artifacts, since various methods used by different groups may measure different fractions of dissolved and/or colloidal and particulate pools. Methods intercomparisons are currently underway that could help to clarify these issues. 

In our previous investigations of the amounts and distribution of mercury in the surface waters of the northwest Atlantic Ocean, we found a mean total mercury concentration of 7 ng/1. and a range of 6-11 ng/1. (26). Also, we found in open ocean surface waters no significant difference between the mercury concentrations measured directly in pre-acidified seawater ( reactive mercury) and the total mercury determination in the organic free samples. In the work shown in Table II, we also found no significant difference between the reactive mercury determination and the total mercury measurement, which was carried out in approximately one third of the samples. The total mercury measurements appear in the square brackets for the results tabulated in Table II. 

From Mc2Hg data in surface sea water samples and in the corresponding marine atmosphere, a first estimation of the transfer of this compound from the Southern Ocean, the Arctic Ocean and the Atlantic Ocean was carried out by equation (1) (see Table 7.7) (45). This estimate was calculated under the questionable assumptions that the measured data were representative for the whole area and that no seasonal variation occurs. The great uncertainty in such calculations can also be inferred by the great variability in the data for the total biogenic Hg emission from all oceans, which range from 0.6 10 to 7700 10 g yr (66, 67). However, the calculated input of more than 0.2 10 g yr of Hg as Mc2Hg from each of the polar oceans is more than 10% of the total emission of this heavy metal species from the Atlantic Ocean. In addition, more recent data from Lindqvist et al. and... 

This paper discusses studies of sea surface films observed and collected in the southern California Bight and the U. S. Middle Atlantic Bight. The goals of these studies were to understand the relationship between chemical composition and surface elasticity in these complex natural films and to determine the range of surface elasticity typical of the ocean surface. Mass spectrometry was the principal analytical tool because of its capacity to characterise and identify chemical structures for many compound classes and to provide a quick assessment of compounds enriched in sea surface films. We present typical variations in SAOM chemical composition as reflected in mass spectral patterns and show the effect of these compositional variations on the film elasticity. 

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