Estimating and Modeling Air-sea Gas Fluxes in the Southern Ocean

本项目研究的是控制南极绕极流和南大洋中可溶气体——特别是氯氟化碳、二氧化碳和氧气——的海气通量的机制。研究的目标有三个：(1)更好地理解中尺度海洋过程对示踪剂输运的影响，以及如何在粗分辨率模式中表示这些过程；(2)基于我们对海气通量、海洋运输和生物地球化学转化之间关系的理解，开发一种评估海气通量的创新诊断方法；(3)对南大洋生物地球化学循环的明确模型进行测试，并将其应用于观测，以产生独立的海气碳和氧通量估算。现有的全球模型将被用作测试平台。该模型目前代表了理想化参数化的关键生物地球化学过程，但这些足以对该诊断方法的基本假设进行初步测试。全球生物地球化学模型的继续发展将与这项诊断工作同时进行。这种方法在补充目前估算南极环极流海气通量的方法方面具有很大的潜在实用价值。它将提供物理和生物地球化学过程之间联系的明确描述，并将大大提高这种模式的一般预测能力。

This project is a study of the mechanisms controlling the air-sea flux of soluble gases - in particular chlorofluorocarbons (CFC's), carbon dioxide, and oxygen - in the Antarctic Circumpolar Current and the Southern Ocean. There are three objectives to the study: (1) a better understanding of the influence of mesoscale oceanic processes on tracer transport, and how to represent those processes in coarse resolution models; (2) the development of an innovative diagnostic approach to evaluating air-sea gas fluxes rooted in our understanding of the relationship between air-sea fluxes, ocean transports and biogeochemical transformations, and (3) testing this approach against explicit models of southern ocean biogeochemical cyclesand apply it to observations to yield independent estimates air-sea carbon and oxygen flux.An existing global model will be used as a testbed. This model currently represents key biogeochemical processes with idealized parameterizations, however these are sufficient for an initial test of the basic assumptions of this diagnostic approach. The continued development of the global biogeochemical model will occur in parallel with this diagnostic work. This approach has great potential practical utility in supplementing current methods of estimating air-sea gas fluxes in the Antarctic Circumpolar Current. It will provide an explicit description of the connections between physical and biogeochemical processes, and will significantly improve the prognostic capabilities of such models in general.