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

*9531975米切尔本研究项目是美国联合全球海洋通量研究(JGOFS)南大洋计划的一部分，旨在(1)更好地了解南大洋有机和无机碳的通量，(2)确定调节这些通量的大小和变化的物理、生态和生物地球化学因素和过程，以及(3)将这些通量置于当代全球碳循环的背景下。全球海洋通量联合研究(JGOFS)已在北大西洋、赤道太平洋和阿拉伯海取得了三项成功的实地工作，最后一项主要实地工作将在南大洋。JGOFS的总体目标是确定和了解控制碳和相关生物元素随时间变化的通量的过程，并预测海洋生物地球化学过程对气候变化的反应。根据南大洋的大小和其中发生的物理过程(如深水和中水形成)判断，南大洋在全球碳循环中至关重要，但其目前的定量作用尚不确定。该项目涉及建立海水光学性质与碳基生物参数浓度之间的关系，如浮游植物色素、颗粒有机碳以及海洋上层有机碳的形成和输出。其目标既是研究低稳定性南大洋环境中的生化过程，又是开发用于解释遥感海洋颜色图像的算法。现场数据将从一个仪表化海洋浮标获得，该浮标将在南大洋实验的其他调查人员提供的实际过程数据的背景下，提供关于光谱反射率、光衰减和散射系数的详细信息。通过该项目开发的信息和理解将直接提高我们推断南大洋碳通量系统的时间和空间尺度的能力，并使我们能够开发更准确的系统模型和解释生态系统的长期变化。

*** 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.