Continental Effect

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This simple picture does not explain the gradual increase in 818Omw values north of the Himalayan crest. Mean elevation of sampling sites north of the crest lies almost entirely within 4500 500 m, and even increases slightly northward, the opposite of the expected pattern where elevation is the main determinant of 8lsOmw values. Likewise, the continentality effect—simple rain out of air masses with distance from coastlines—should cause 818Omw values to decrease inland, not decrease. 

Fig. 9.14 Lines of equal <5D values for Europe, based on over 300 samples of groundwater. A trend of lighter isotopic composition is seen as a function of the distance from the ocean, reflecting the continental effect in the precipitation. (After Sonntag et al., 1979.)...

Cuntz M., Ciais P., and Hoffmann G. (2002) Modelling the continental effect of oxygen isotopes over Eurasia. Tellus Ser. B Chem. Phys. Meteorol. 54(5), 895-909. 

Table 10-14 shows a number of data for particulate sulfate over the open ocean under conditions eliminating continental effects as far as possible. As noted earlier, the marine aerosol contains sulfate from seasalt, as well as sulfate arising from the oxidation of sulfur compounds in the gas phase. The latter fraction is called excess sulfate. As described in Section 7.5, the excess can be determined either by a size fractionation of the aerosol or... 

The altitude effecf and the continental effecf (Rozanski et al. 1993) refer to the tendencies for and 5D of precipitation to become progressively lower towards continental interiors and higher elevations. The altitude effect includes important control by temperature. Both may reflect a stochastic tendency for air masses moving away from moisture sources to encounter conditions (frontal/convective) that cause moisture extraction and so isotopic fractionation for °0 and D H it is possible that modeling of and 5D of precipitation could involve stochastic treatments. As reviewed by Rozanski et al. (1993), the continentality depletion for 5 0 of precipitation reaches 8 per mil over 4500 km into Europe from the Atlantic coast. This continental effect is more pronounced in winter than in summer, perhaps because evapotranspiration returns most summertime precipitation to the atmosphere, whereas runoff is more important in wintertime. 

M. J. Cmickshank and C. L. Morgan, Synthesis andMnalysis of Existing Information KegardingEnvironmental Effects of Marine Mining, consulting report to Continental Shelf Associates for U.S. MMS Contract No. 14-35-0001-30588, U.S. Dept, of the Interior, Washington, D.C., 1992. 

For flow tested combinations, see a few typical data in Table 7-12. Note, for example, that using a Continental disk reverse acting knife blade rupture disc with a Crosby JOS/JBS pressure relief valve that the combined effect is to multiply the rated capacity of the Crosby valve by a multiplier of 0.985 for a set pressure in the 60-74 psig range... 

Locomotive diesels As larger volumes of coolant are required in railway locomotives than in road vehicles, the cost of inhibition is proportionally greater. An additional factor is the possibility of cavitation attack of cylinder liners. These considerations place a restriction on the choice of inhibitors. In the past, chromates have been used at concentrations of up to 0-4%, but their use presents handling and disposal problems. Chromates cannot be used with ethanediol antifreeze solutions. A IS I borate-metasilicate at a concentration of 1 % has been used in the UK. Nitrate is added to this to improve inhibition of aluminium alloy corrosion. Tannins and soluble oils are also used, but probably to a lesser extent than in the past. The benzoate-nitrite formulation (formerly BS 3151) is effective and has been used by continental railways . ... 

The movement of Earth s crustal plates and the continents they contain - continental drift -has had enormous effects on climate, sea levels, and the distributions of organisms. Mass extinctions of organisms have usually accompanied major drops in sea levels. The collision of all the continents to form the gigantic landmass called Pangaea about 260 million years ago, triggered massive volcanic eruptions. The volcanoes... 

This chapter examines climatic and tectonic controls on erosion in the tropics and the implications of these observations regarding the composition of erosion products in general. The role of glaciations in continental denudation will then be examined and contrasted with tropical conditions. Finally, we will briefly examine human effects. 

Many important erosion-related phenomena are episodic and infrequent, such as flash floods, landslides, and glaciations, while others such as orogenesis and soil formation involve time scales that exceed those of major climate fluctuations. In either case, the time scale of human existence is too short to make adequate observations. Consequently, it is difficult to directly estimate the rates or characterize the effects of such phenomena on erosion products. The key to understanding weathering and erosion, on a continental scale, is to decipher the relationship between landforms, the processes that produce them, and the chemistry and discharge of river-borne materials. 

The Effects of Transients Continental Ice Sheets and Human Technology... 

It has been argued that phosphorus limits oceanic productivity on the million year time scale (Broecker, 1971). The reason is that essentially all phosphorus in the ocean is introduced by rivers and thus ultimately from the weathering of continental rocks. This flux is, in effect. 

The survey of geographical distribution patterns of secondary plant constitnents starts with examples that come, more or less, from within continents. In many examples, the patterns of variation involve comparatively small areas, a few connties perhaps, and could be referred to as local whereas in others, considerably larger areas are involved, often several states or provinces, or even large pieces of a country. In most cases, however, the regions nnder consideration lie within a single continental land-mass. A few examples come from island systems (e.g., New Zealand) where the existence of major landmasses separated by a small stretch of water does not appear to have had an effect upon the distribution reported, or at least none has been reported. 

Lake Common loon Adult Blood, egg Widespread distribution and easily studied large existing database sensitivity to Hg existing database for continental Hg exposure and lab and field effects... 

Figure 22. U-Th equiline diagram showing U-Th isotopes may be sensitive to the effects of assimilation of pre-existing (>350 kyr) arc basalts or continental crast. This is much more complicated using long-lived isotopic systems (e.g., Sr/ Sr or " Nd/ " " Nd) because in these systems pre-existing arc basalts will be indistinguishable from new magmas and crastal assimilation will be hard to distinguish from subducted sediment addition unless assimilation is coupled to differentiation.

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