ABSTRACT Understanding the mechanisms and rates of carbon removal from surface waters remains an important goal of the Joint Global Oceanographic Flux Study (JGOFS). Particle formation and sinking is an important process for such removal. Much of the particulate fraction in surface waters is in the form of small cells having slow sinking rates. For these cells to sink more rapidly, they need to be packaged into larger particles. Fecal pellet production by animals provides one way of doing this; aggregate formation another. Because aggregates are the dominant form of sedimenting particles, understanding the processes that form and destroy aggregates is crucial for JGOS to achieve its goal. This proposal will develop models to increase our understanding of the processes affecting organic matter export from the surface mixed layer. To this end, the models will combine particle aggregation models with plankton food web models. Data sets from the JGOFS process and time-series studies will be used to determine and refine the ability of the models to predict carbon export. Data collected during the JGOFS field programs will be used to refine the models. Combining the simulation results with JGOFS field data will increase our understanding of the processes affecting vertical export fluxes and improve the accuracy of flux predictions made using the models. The results of this work will increase significantly our ability to accurately describe the movement of organic material from the surface to the deeper parts of the ocean.
