A New Method for the Estimation of Profiles of Diffusivity in the Stratified Marine Environment

分层海洋环境中扩散率剖面估计的新方法

基本信息

批准号：
NE/F019467/1
负责人：
Tom Rippeth
金额：
$ 25.99万
依托单位：
Bangor University
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2009
资助国家：
英国
起止时间：
2009 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FF019467%2F1
关键词：
New Method Estimation Profiles Diffusivity

项目摘要

Much of the ocean is stably stratified with lighter water overlying heavier water, with the vertical movement of nutrients, salt, heat, and pollutants across stratification driven by turbulent mixing. The nature and strength of the processes which are responsible for these vertical fluxes therefore play a major role in shaping the marine system. For example, vertical fluxes of nutrients link the dark, nutrient-rich, deep waters with the upper, sunlit, part of the water column promoting the primary productivity which supports the marine ecosystem. Vertical mixing is also one of the main mechanisms behind the large scale ocean circulation, and therefore of immense importance for the climate of our planet. A number of techniques have been developed for the estimation of vertical mixing rates in the marine environment. These include direct measurements of the turbulence using a freefalling profiler, which is a very time consuming and labour intensive technique requiring teams of specialist scientists. Other methods use acoustic current meters, which can be deployed in the marine environment and then left for a period of time. However, this method has a limited vertical range, and up until now has not worked well in environments with vertical stratification or when deployed from moving platforms. Our proposal here is to extend an acoustic technique, which we have developed, for measuring marine turbulence, using relatively cheap, off-the-shelf instruments, to the stratified marine environment. Our aim is to develop a simple to operate and effective add-on system that can be used on conventional profiling platforms (i.e. CTDs), for the measurement of profiles turbulence in a stratified marine environment. Such a system would significantly simplify measuring oceanic turbulence, facilitating more turbulence measurements and enabling an improved understanding of this important process.

大部分海洋都稳定地分层，较轻的水，较重的水，养分，盐，热和污染物的垂直移动在湍流混合驱动的分层之间。因此，负责这些垂直通量的过程的性质和强度在塑造海洋系统中起着重要作用。例如，养分的垂直通量将深色，营养丰富的深水与水柱的上部，阳光，促进支持海洋生态系统的主要生产力的一部分联系起来。垂直混合也是大型海洋循环背后的主要机制之一，因此对于我们地球的气候非常重要。已经开发了许多用于估计海洋环境中垂直混合速率的技术。其中包括使用自由降落的分析师直接测量湍流，这是一项非常耗时且劳动密集型的技术，需要专家科学家团队。其他方法使用声流仪表，可以在海洋环境中部署，然后离开一段时间。但是，该方法的垂直范围有限，到目前为止，在垂直分层或从移动平台中部署时的环境中效果不佳。我们在这里的建议是将一种声学技术扩展到我们已经开发的，用于测量海洋湍流，使用相对便宜的现成的仪器到分层的海洋环境。我们的目的是开发一种易于操作和有效的附加系统，该系统可用于常规分析平台（即CTD），以测量分层的海洋环境中的概况湍流。这样的系统将大大简化测量海洋湍流，促进更多的湍流测量结果，并能够提高人们对这一重要过程的了解。