The Agulhas Undercurrent Experiment

Beal最近观察到一股强烈的、明显持续的奥古拉斯暗流(AUC)，这引发了一系列挑衅性的问题。这项研究的主要问题是AUC的纬度范围是什么及其在温盐环流中的作用？AUC路径上的速度、位涡和水团结构的演变和强迫是什么？如何量化AUC与西部边界流水的混合/夹带并确定AUC内热量和质量的绝对通量？AUC输送的平均和时间变异性是什么？提出了一种水文巡航，在此期间将测量AUC的4个电导率-温度-深度和降低的声学多普勒流速剖面仪断面。沿32S方向的短系泊阵列也将部署。三个系泊平台将每个包含3米的间隔，以捕获AUC运输。它们将被限制在水柱较低的1000米处，并被设计为监测长达2年，但可能会更早被找回。主要的波动周期预计为30-40天。系泊设备、仪表和相关技术人员将由南安普顿海洋中心免费提供给NSF。一条间距为50公里的站点线将连接路段封闭箱的近海末端，以便进行财产平衡评估。将在南纬26度至南纬37度的1800米沿线铺设一条间距100公里的测站线，以估算潜流的纬度范围。每个测站将包括24个瓶子的电导率-温度-深度、溶解氧和降低的声学多普勒海流剖面仪数据，以供ODF人员校准到WOCE标准。邮轮大约需要28天。

0244769BealRecent 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.