The Development and Testing of a New Technique for the Estimation of Profiles of Epsilon using an Acoustic Doppler Current Profiler (ADCP)

尽管大陆架海只占世界海洋表面的一小部分(~7%)，但它们被认为对开放海洋的二氧化碳储存做出了重大贡献(占总数的20%至50%)。从大气中吸收二氧化碳是由生物泵驱动的，生物泵只在陆架海季节性分层的区域有效。这种泵的一个限制部件是垂直混合，它通过季节性温跃层向真光层提供营养物质，从而支持新的初级生产。虽然剖面仪技术已成功地用于通过测量epsilon剖面(湍流动能耗散率)来估计垂直混合速率，但这些技术昂贵且耗时，因此测量仅限于短时间段(12-24小时)。我们的建议是在雷达气象学已经使用的技术的基础上发展一种新的技术，该技术使用现成的常规ADCP来测量温跃层中epsilon垂直结构的长时间序列。这项技术最初将应用于我们已经收集的数据，结果将与同时收集的epsilon剖面仪测量结果进行验证。我们还建议在更基本的层面上测试这项技术--使用光谱技术--在我们建议在梅奈海峡收集的数据上。

Although Continental shelf seas make up a relatively small fraction (~7%) of the world ocean's surface they are thought to make a major contribution (accounting for between 20 and 50% of the total) to the open ocean storage of CO2. The drawdown of CO2 from the atmosphere is driven by a biological pump which is only effective in seasonally stratified zones of the shelf seas. A limiting component of this pump is the vertical mixing which supplies nutrients across the seasonal thermocline to the euphotic zone, thus supporting new primary production. Whilst profiler techniques have been successfully used to estimate the vertical mixing rate through measurement of profiles of epsilon (the rate of dissipation of turbulent kinetic energy) these techniques are costly and time consuming and so measurements limited to short (12-24 hours) periods of time. Our proposal is to develop a new technique, based on a technique already used in Radar Meteorology, which uses a convensional off the shelf ADCP, to measure long time series of the vertical structure of epsilon in the thermocline. The technique will initially be applied to data we have already collected, and the results will be validated against simultaneously collected profiler measurements of epsilon. We also propose to test the technique at a more fundamental level - using spectral techniques - on data which we propose to collect in the Menai Strait.