Collaborative Research: Transport, Transformation and Utilization of Dissolved Organic Matter in the NE Atlantic Ocean

College Of William & Mary Virginia Institute Of Marine Science, Gloucester Point VA

Investigators

Abstract

ABSTRACT OCE-0095223 and OCE-0095090 The process of dissolved organic matter (DOM) transport toward export regions has been inferred mostly from a few sections showing surface accumulation of enhanced dissolved organic carbon (DOC) concentration and penetration to depth. Decomposition during flow from source regions to export sites has not been studied, nor has the accompanying transport of dissolved organic nitrogen and phosphorus (DON and DOP). In this project, researchers at the Virginia Institute of Marine Science and the Rosenstiel School of Marine and Atmospheric Sciences will observe the transport of accumulated DOC, DON and DOP during the spring phytoplankton bloom in the NE Atlantic Ocean, the region previously studied in the JGOFS North Atlantic Bloom Experiment. They will track the transport and simultaneous decomposition of both the overwintering and newly-produced DOM as it flows through the NE Atlantic toward a site of bottom water formation to the northeast of the U.K. in the Norwegian Sea. This project will take advantage of an opportunity to participate on a detailed hydrographic survey of the NE Atlantic in spring 2001 aboard the U.K. research vessel RRS CHARLES DARWIN with colleagues from the George Deacon Division of the Southampton Oceanography Centre (SOC), U.K. A principal cruise objective is to calculate volume transports, from which mass transport of DOM can be estimated. While the broad outlines of these processes have now been sketched in, there have been no detailed studies in which DOM transport has been explicitly studied in the relevant hydrographic framework, and none in which simultaneous estimates of underway decomposition have been determined. This study, a collaboration among biogeochemists, microbial ecologists, and physical oceanographers would be the first to provide synoptic data on DOC, DON and DOP concentrations, volume transports and decomposition rates, from which mass transport of DOM components can be assessed.