Sources and sinks of oceanic hydrogen sulfide – an overview

In recent years hydrogen sulfide (H2S) has played a decreasing role in the global sulfur budget, and is discussed today primarily in terms of local impacts. This discussion focuses on two of the remaining global issues, namely the atmospheric concentration of H2S over the remote ocean and the flux of H2S between the ocean and the atmosphere. Available information on the measurements of H2S in the remote oceanic atmosphere is evaluated through consideration of previous data and analytical methods. Production and loss of H2S in the ocean is discussed, and potential sources and sinks of any H2S over the open ocean briefly reviewed, the issue of the oceanic contribution of H2S to the remote oceanic atmosphere is then addressed. Based on the concentrations reported for H2S in the remote marine atmosphere, consideration of the analytical technique used to measure the H2S, and the potential oceanic sources of H2S, it is concluded that there is little evidence for any H2S in the remote marine atmosphere being of marine origin.