Optical Measurements and Modeling to Estimate Concentrations and Fluxes of Organic Matter in the Southern Ocean

点击翻译按钮获取中文摘要

*** 9531975 Mitchell This research project is part of the US Joint Global Ocean Flux Study (JGOFS) Southern Ocean Program aimed at (1) a better understanding of the fluxes of carbon, both organic and inorganic, in the Southern Ocean, (2) identifying the physical, ecological, and biogeochemical factors and processes which regulate the magnitude and variability of these fluxes, and (3) placing these fluxes into the context of the contemporary global carbon cycle. The Joint Global Ocean Flux Study (JGOFS) has had three successful field efforts (in the North Atlantic, equatorial Pacific, and the Arabian Sea), and the last major field effort will be in the Southern Ocean. The overall objectives of JGOFS are to determine and understand processes controlling the time-varying fluxes of carbon and associated biogenic elements, and to predict the response of marine biogeochemical processes to climatic change. The Southern Ocean is critical in the global carbon cycle, as judged by its size and the physical processes which occur in it (e.g. deep and intermediate water formation), but its present quantitative role is uncertain. This project concerns the development of relationships between the optical properties of sea water and the concentrations of carbon-based biological parameters such as phytoplankton pigments, particulate organic carbon, and the formation and export of organic carbon from the upper layers of the ocean. The objectives are both to investigate biochemical processes in the low stability Southern Ocean environment, and to develop algorithms for the interpretation of remotely sensed ocean color images. The in situ data will be obtained from an instrumented ocean buoy that will provide detailed information on the spectral reflectance, light attenuation, and scattering coefficients in the context of actual process data provided by other investigators in the Southern Ocean Experiment. The information and understanding developed through this project will directly improve our abil ity to extrapolate the time and space scales of the Southern Ocean carbon flux system, and allow the development of more accurate system models and the interpretation of long-term changes in the ecosystem.