Regulation of O₂, N₂ and CO₂ in the atmosphere; thoughts of a laboratory chemist

Abstract

The real system (air + sea + sediments) is compared with an equilibrium model, an imaginary system containing the same components at equilibrium. In the model, the presence of five aluminosilicate phases (six, if Fe is included) SiO2 and CaCO3 will fix the concentrations of the major ions, pH, and p(CO2), if temperature and [Cl-] are given. It is suggested that the real system behaves similarly to the model. The T-dependence of p(CO2) may be a more important factor than industrial activity. The behavior of the equilibrium model system on reduction is described; it may resemble earlier states of our real system. The present p(O2) is probably regulated by a steady state, even if some data might seem to indicate the equilibrium (3) to be nearly fulfilled. Nitrogen exists as N2 instead of the equilibrium form, NO3?. There is a nitrate sink close to the surface of the ocean, but the explanation still seems to be unknown.DOI: 10.1111/j.2153-3490.1966.tb00226.x 1966 Blackwell Munksgaard