New Problems for Chemical Oceanographers

Abstract

WILLIAM DITTMAR PUBLISHED HIS RESULTS FROM THE FIRST 2 years of the H.M.S. Challenger expedition almost 100 years ago (I). His results demonstrated that, to a very good first approximation, seawater could be considered a two-component system (water and sea salt). Consequently, 99.5% (by weight) of all the chemical components of seawater became relatively uninteresting to water-column chemists. However, 80 of the elements of the periodic table could be found in the remaining 0.5%. Consequently, marine chemists have tended to concentrate on the minor and trace components of seawater because the interesting variations occur in them; that is, they reveal information about the processes and mechanisms that influence the chemistry of seawater. Chemical oceanographers, as all scientists do when their field of study matures, naturally progress from the survey mode to process-oriented investigations, from correlations of observations to hypotheses of mechanisms, and from the general understanding of the chemistry of seawater to highly specialized and focused interests. Evolution of Chemical OceanographyChemical oceanography has evolved from the study of the major elements to the investigation of minor components-the nutrients, silica, and dissolved oxygen-then on to radiotracers, trace metals, organics, and bio-