Norman H. Cutshall Oak Ridge National Laboratory Oak Ridge. Tennessee 37830
A Chemist's View of Oceanography
Oceanography, although not a new scientific field, has recently grown so much in popular interest that it seems t o be new tomany people. ~ h k o m a n t i appeal c of aphysical frontier, together with the intense environmental concern among younger people, has made oceanography a glamour field during the 1960's and early 1970's. My goal here is to discuss this field from the aspect of a chemist. I t is important to emphasize that other aspects are available and that the perception of oceanoera~hv on the backeround of the - - - denends . viewer. I must also confess at the outset to a ~ t o l e m a i view c of the oceanographicuniverse with chemistry a t the center and the other sciences orbiting in the periphery. The reader is, therefore, warned that a different scene would be found by another eye applied to Steinbeck's "peep hole which looks out a t the world".' The Structure of Oceanogradv - . .
I t has been said that oceanographers are individuals from the basic sciences who conduct their practice in a marine context. Most oceanographers do indeed have academic backgrounds which resemble backgrounds of chemists, physicists, biologists or geologists. Correspondingly, in most US. educational institutions that offer oceanography majors, the programs are a t graduate level and require a baccalaureate in chemistry, physics, biology or geology. Formal graduate education in oceanography generally involves specialization in chemical, physical, biological or geological oceanography. These attributes are held in common with the other composite "earth sciences," geophysics and meterology. Even thoueh it is nossible to identifv the central nronerties of the constiiuent sEiences within oc&nography, doundaries between them are both arbitram and unnatural in actual research situations.'l'he primary reason for maintaining identification with a hasic field is to recoeni7e the context within which such a conclusion is drawn. An example may illustrate what I mean: At a National meeting of the American Association for the Advancement of Science a physical oceanogmpher proclaimed "The sun shines on the ocean and photosynthesis occurs." In the context of energetics the statement was appropriate and accurate. A biologist, however, would certainly have mentioned plants or even a more specific taxon in any statement on photosynthesis. A chemist, on the other hand, would have referred to the conversion of carbon dioxide and water to molecular oxveen ... and oreanic matter. A eeoloaist - .. would be likely to mention sedimentation of diatom frustules that followsa oeriod of hirh oceanic nroductivitv. Each view would be correct despite iheir apparent divergenee. It is only bv combinine all such views, however, that a more comprehensive, eco&cal insight ii developid. The coalescen~eof different views to brine-a smcific problem or process into f m . is one of the most stimulating characterist& of oceanography. Chemists in Oceanography . . . Chemists in oceanography think ahout theocean firstly in terms of the elemental composition of the solution and particulate phases. Secondly, they seek to know the mechanisms and kinetics of interaction among the constituent elements. All of the well known chemical 5pecialties are adaptable to ~
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162 1 Journal of Chemical Education
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marine studies. Inorganic and physical chemists deal with ionic and heterogeneous equilibria, chemical speciation, and the thermodynamic activities of the species. Organic chemists study the multitude of organic compounds found in seawater and esneciallv in marine sediments. Biochemists work cloaelv with tLe organic chemists to study the production, degradation and bioloeical effects of these com~ounds.While each of the specializa%ons of chemistry h a i a place in chemical oceanoera~hv.the most needed chemist in oceanography . -~ is the anaiytica"chemist. Most of the effort in chemical oceanoeranhv is expended in analvsis: all of the progress depends . . on good analises and many of the errors are based on faulty analyses. Many factors combine to make the analyst's task in oceanography exceedingly formidible. Although the solute concentration of seawater is 3.5% and while all the natural elements are found or presumed to be nresent in seawater, only a few of the elemekal concentrations exceed 1mgn
