Collaborative Research: Exploring the Role of Internal Wave Generation in Gravity Currents

由于密集海洋重力流的夹带对海洋翻转环流的重要性，过去人们对其进行了深入的研究。这些研究只对产生夹带的实际过程进行了很少的检查，并且历史上没有将内部重力波（igw）的产生与重力流联系起来。这与许多关于大气下坡风流动的大气研究形成了对比，在这些研究中，IGW的产生已经被发现是一个重要的过程，并负责大量的动量转移。在海洋溢流中，很少有历史观测能捕捉到探测内波产生所必需的尺度。然而，基于对有限的现有数据的重新分析，至少一些溢出具有有利于IGW产生的垂直结构和时间尺度范围。我们假设IGW的产生代表了地中海外流（Med Outflow）的动量汇。该项目将与西班牙科学家合作，研究地中海外流中igw的存在、特征和动态作用。计划进行两次短期系泊和密集的船上LADCP/CTD调查，以探索IGW结构，并检查它是否可能对重力流动力学和夹带很重要。这项研究提供了一个战略机会，以启动国际，欧美合作。

Entrainment in dense oceanic gravity currents has been studied intensively in the past owing to its importance for the oceanic overturning circulation. These studies contain only little examination of the actual processes that produce the entrainment, and have historically not been linked the generation of internal gravity waves (IGWs) with gravity current flows. This contrasts many atmospheric studies of atmospheric down slope wind flows in which IGW generation has been found to be an essential process and responsible for a significant amount of momentum transfer. In oceanic overflows, few historical observations capture the scales necessary to detect internal wave generation. However, based on a reanalysis of the limited available data, at least some overflows have a vertical structure and range of temporal scales conducive to IGW generation. We hypothesize that IGW generation represents a momentum sink in the Mediterranean Outflow (Med Outflow). The project will examine the presence, characteristics, and dynamic role of IGWs in the Med Outflow in collaboration with Spanish scientists. Two short-term moorings and intensive shipboard LADCP/CTD surveys are planed to explore the IGW structure and to examine if it is likely to be important for gravity current dynamics and entrainment. This study offers a strategic opportunity to initiate an international, European-American collaboration.