The death of Agulhas rings and the emergence of a modified Brazil Current

西南大西洋环流受环流和西边界流的强烈影响。据推测，汇流区的漂移在很大程度上是由于来自南北交汇处的上游洋流(即巴西洋流和马尔维纳斯洋流)的输送不同所致。该项目调查了阿古拉斯环可能对巴西海流变化的影响。尽管阿古拉斯环在穿越整个南大西洋时失去了大量的力量和能量，但它们从一开始就如此巨大和充满活力，当它们到达巴西洋流并融入其中时，它们对能量平衡仍然非常重要。阿古拉斯环被巴西流上游吸收是一个非线性过程，主要目的是利用分析模型和面向过程的数值模拟相结合的方法来确定阿古拉斯环对巴西流时间变化的影响。这个问题在过去受到的关注很少，主要是因为它是一个非常困难的非线性问题。诺夫博士之前在同一主题上的研究表明，要确定环是会加强还是削弱巴西海流，并不是一件简单的事情。他和他的合作者现在已经开发出了分析和数值技术，这应该是我们第一次能够给出上述问题的答案。广泛的影响：这项研究将通过以下方式造福社会：(I)教育一个新的博士；(Ii)在Live Oak的佛罗里达州警长青年分会为贫困儿童提供持续的一系列讲座和演示。

The western South Atlantic circulation is strongly affected by rings and western boundary currents. It has been surmised that the drift of the Confluence Zone is in large part due to variations in the transports of the upstream currents approaching the confluence from the north and south (i.e., the Brazil and Malvinas currents). The project investigates the influence that Agulhas rings may have on the Brazil Current variability. Although Agulhas rings lose much of their strength and energy as they cross the entire South Atlantic, they are so large and energetic to begin with that they are still very important to the energy balance when they reach the Brazil Current and blend into it. The absorption of Agulhas rings upstream by the Brazil Current is a nonlinear process and the main goal is to determine the influence of Agulhas rings on the temporal variation of the Brazil Current using a combination of analytical models and process-oriented numerical simulations.Intellectual merit: New observations using satellite data vividly illustrate the importance of the above eddy-current interaction problem. The problem received limited attention in the past primarily because it is a very difficult nonlinear problem. Dr. Nof's previous work on the very same subject has shown that it is not a simple matter to determine whether the rings would strengthen or weaken the Brazil Current. He and collaborators have now developed analytical and numerical techniques, which should, for the first time, enable us to give the answer to the above question.Broader impacts: The study would benefit society by (i) the education of a new Ph.D., and (ii) providing a continuous series of lectures and demonstrations to unprivileged kids at the Florida Sheriffs Youth Branch in Live Oak.