Collaborative Research: Dynamics and Transport of the Antarctic Circumpolar Current in Drake Passage (cDrake) Analysis

由巨大的南极绕极洋流(ACC)主导的南大洋正在对气候变化做出显著响应，在过去30年里，受环极风的驱动，在过去50年里，南大洋变暖的程度明显高于全球海洋。从地理上讲，德雷克海峡提供了一个天然的？瓶颈？用于测量ACC分量流的时变传输。反过来，这又为我们提供了一种测量脉搏的方法。对南大洋环流的影响。CDrake野外试验是国际海洋年的一个项目，旨在解决ACC在四年期间的季节变化和年际变化。使用一组(~40)底部系泊电流和压力记录的反向回声测深仪(CPIES)，测量海底压力以及12kHZ声脉冲往返地面的旅行时间，在5年的时间跨度内收集了网格阵列上的速度和温度分布的时间序列。将对CPIE和辅助水文数据集(例如CTD、ADCP和XBT)进行全面分析，以解决ACC的输送变异性，将其垂直结构划分为正压和斜压分量，并将其横向结构划分为组成Drake海峡ACC的许多急流和锋面。

The Southern Ocean, dominated by the huge Antarctic Circumpolar Current (ACC), is responding markedly to climate change, being driven by circumpolar winds that have increased over the past ~30 years, and warming significantly more that the global ocean over the past ~50 years. Geographically, the Drake passage provides a natural ?chokepoint? for measuring the time varying transport of the ACC component flows. In turn this provides us with a means of taking the ?pulse? of the Southern Ocean circulation. The cDrake field experiment is an IPY project to resolve seasonal to interannual variability of the ACC over a four year period. Using an array of (~40) bottom-moored Current and Pressure-recording Inverted Echo Sounders (CPIES) which measure bottom pressure along with the travel time of 12kHZ sound pulses to and from the surface, a time series of velocity and temperature profiles over a grid array has been assembled over a 5 year timespan. A full analysis of the CPIE and ancillary hydrographic data sets (e.g. CTD, ADCP and XBT) will be undertaken to resolve the ACC transport variability, partition its vertical structure between barotropic and baroclinic components, and its lateral structure partitioned between the many jets and fronts that comprise the ACC in the Drake Passage.