1971). Regional rates of exchange, however, have been estimated only 

 from a few calculations, based on local carbon dioxide partial pressure 

 and wind data (Teal and Kanwisher, 1966), from changes inferred in 

 surface-water oxygen content resulting from biological processes, 

 based upon consideration of changes in nutrient distributions (Red- 

 field, 1948), from recent indirect measurements utihzing tracer gases 

 (Broecker and Kaufman, 1970), and from in situ cuvette techniques 

 (Coyne and Kelley 1972). 



Aside from the human input of gases to the atmosphere and the sea, 

 there is the unresolved set of questions about gases produced by natural 

 processes in the sea, their genesis, and transport associated with their 

 distribution and exchange across the ocean-atmosphere interface 

 (Swinnerton et al., 1970; and Hahn, 1972). The processes involved in 

 the interaction of these gases with other chemical constituents of the 

 sea and with the marine biosphere are not well understood. In addition, 

 rivers and streams are an important means of removing such gases as 

 carbon dioxide from the continents and introducing them into the sea 

 (Gordon et al., 1971 : and Kelley and Hood, 1971). 



Gases may be either chemically reactive or nonreactive in seawater. 

 Carbon dioxide, sulfur dioxide, ammonia, nitrogen oxides, etc., are 

 acid or base anhydrides and their air-sea transport mechanisms are 

 more or less afi'ected by their aqueous chemistry (Quinn and Otto, 

 1971). The class of nonreactive gases represented by methane, carbon 

 monoxide, hydrogen, and helium have transport processes unaffected 

 by an aqueous chemistry of this type. However, the nature of their roles 

 as solutes may depend largely upon the formation of hydrates of clathrate 

 structures in seawater, especially in cold and high pressure environments. 



Because the gases whose balances are upset by man include both 

 reactive and unreactive, the air-sea exchange mechanisms and rates 

 of exchange should be examined for both classes. In particular, air- 

 sea transfer coefficients of these gases should be studied. These data 

 could then be used with field observations to calculate regional and 

 mesoscale fluxes on a time-dependent basis. Global-scale fluxes in some 

 cases where human and natural production figures are available are 

 perhaps better approached by calculation (Craig, 1957; Revelle and 

 Suess, 1957; Broecker et al., 1971; and Machta, 1972), but this ap- 

 proach might not be applicable to the question of the partitioning of 

 biologically important gases (e.g. carbon dioxide) between the terrestrial 

 biosphere and the oceans (Machta, 1972). 



It has long been known that the sea surface, in general, is not in 

 equilibrium with the atmosphere with respect to carbon dioxide and 

 oxygen, although the departure is not large for oxygen (Craig, 1957). 

 The greater carbon dioxide disequilibrium is related to its lower rate 

 of exchange with the atmosphere. Of basic importance in any attempt 



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