The Agulhas Undercurrent Experiment

[01:18318]最近对一个强烈的、明显持续存在的阿古拉斯暗流（AUC）的观测提出了许多具有挑衅性的问题。本研究解决的主要问题是：AUC的纬向范围及其在温盐环流中的作用是什么？沿AUC路径的速度、位涡度和水团结构的演化和强迫是什么？如何量化与西部边界水流的混合/夹带，并确定AUC内的绝对热量和质量通量？AUC输送的平均和时间变率是什么？提出了一次水文巡航，在此期间将测量AUC的4个电导率-温度-深度和低声多普勒电流剖面。沿着32S部署一个短系泊阵列。三个系泊将每个包含3米的间隔，以捕获AUC运输。它们将被限制在水柱下方1000米的地方，设计用于监测长达2年的时间，但可能会提前回收。预计主要波动周期为30 - 40天。南安普顿海洋学中心将免费向NSF提供系泊、仪表和相关技术人员。一条间隔50公里的测量站线将连接部分闭合盒的海上末端，以便进行财产平衡估算。在南纬26度至37度，沿1800米方向，每隔100公里设一组监测站，以估计暗流的纬度范围。每个测量站将包括电导率-温度-深度、溶解氧和低声多普勒电流剖面仪数据，由ODF人员校准到WOCE标准。这次航行大约需要28天。

0118318BealRecent observations of a strong, apparently persistent, Agulhas Undercurrent (AUC) raise a multitude of provocative questions. The big questions addressed by this study are What are the latitudinal extent of the AUC and its role in the thermohaline circulation?What are the evolution and forcing of the velocity, potential vorticity, and water mass structure along the AUC path?How does one quantify the mixing/entrainment with western boundary current waters and determine the absolute fluxes of heat and mass within the AUC?What are the mean and temporal variability of the transport of the AUC?A hydrographic cruise is proposed during which 4 conductivity-temperature-depth and lowered acoustic Doppler current profiler sections of the AUC will be measured. A short mooring array along 32S will be deployed, as well. Three moorings will each contain 3 meters spaced to capture the AUC transport. They will be confined to the lower 1000 m of the water column and be designed to monitor for up to 2 years, but may be retrieved earlier. The dominant fluctuations are expected to have periods of 30 - 40 days. The moorings, meters, and associated technicians will be provided at no cost to NSF by Southampton Oceanography Centre. A line of stations at 50 km spacing will connect the offshore ends of the sections closing boxes to allow property balance estimation to be done. A line of stations at 100 km spacing will be made along 1800 m from 26S to 37S to estimate the latitudinal extent of the undercurrent. Each station will include conductivity-temperature-depth, dissolved oxygen, and lowered acoustic Doppler current profiler data with 24 bottles for calibration to WOCE standards by ODF personnel. The cruise should require about 28 days.