Evaporation of iodine from the ocean

Abstract

Enrichment of I relative to Cl and Br in the air, in rain, and in river waters has long been known. To understand this enrichment, experiments were performed to examine the possibility of free evaporation of I from the surface of sea water. The experimental results showed that I can ‘vaporize’ because of the oxidation of iodide ions to free I in sea water under irradiation by solar light of wavelength up to about 560 mμ. On the basis of these results, the rate of I escape can be estimated to be 4×1011 g/yr for the whole ocean surface. This value is in fairly good agreement with the global rate of I deposition in rain.