| Methyl iodide (CH3I) is a biogeochemically important trace gas, the origin and fate of which is poorly understood in the oceans. Data from two cruises in the North Atlantic (GASEX98 and Poseidon) and a series of laboratory investigations are presented as an examination of the factors controlling the concentration of methyl iodide in the oceans. The oceanic production rate of methyl iodide was examined using ship-board incubations of natural water samples, collected during the two cruises in the North Atlantic.; The relationships between methyl iodide and a number of photosynthetic pigments, detected and quantified using high-performance liquid chromatography (HPLC), was investigated during a transect of the North Atlantic.; The possibility that marine phytoplankton represent a sink for methyl iodide was examined in six laboratory experiments using two species of marine diatom (Thalassiosira pseudonana and Phaeodactylum tricornutum). These investigations are preliminary studies and provide the basis for future research into the dynamics of methyl iodide in the ocean. (Abstract shortened by UMI.)... |
