The contribution of rainwater to variability in surface ocean hydrogen peroxide

Hydrogen peroxide concentrations have been determined in marine rain from the Gulf of Mexico , the western Atlantic Ocean , and one rain event off the Florida Keys . In several cases, simultaneous measurements of the concentration of H 2 O 2 in the surface ocean were also determined. These measurements were made with the ship under way using a continuous flow sampling system with the intake at the bow. In shallow stratified layers, rain events can increase the existing hydrogen peroxide concentration by a factor greater than 10 and dramatically increase the mean H 2 O 2 concentration of mixed depth layers of 50 m or more. Rain is a significant transient source of H 2 O 2 in the surface ocean.