Hydrography and biogeochemistry during S.A. Agulhas II cruise Agu011, in the SW Indian Ocean, April 2014

Several open-ocean mesoscale features, a "young" warm-core (or anti-cyclonic) eddy at 52°S, an "older" warm-core eddy at 57.5°S, as well as an adjacent cold-core (or cyclonic) eddy at 56°S, were surveyed during a R/V S.A. Agulhas II cruise in April 2014. The main aim of the survey was to obtain hydrographical and biogeochemical profile data for contrasting open-ocean eddies in the Southern Ocean, that will be suitable for comparison and modelling of their heat, salt and nutrient characteristics, and the changes that occur in these properties as warm-core eddies migrate from the polar front southwards into the Southern Ocean. A total of 18 CTD stations were occupied in a sector south of the South-West Indian Ridge, along three transects crossing several mesoscale features identified from satellite altimetry data prior to the cruise.

2014年4月，科研团队依托R/V S.A. Agulhas II号科考航次，对多个开阔大洋中尺度涡旋特征开展了实地调查，涵盖位于52°S的“年轻”暖核（反气旋）涡旋（warm-core (anti-cyclonic) eddy）、位于57.5°S的“发育较久”暖核涡旋，以及毗邻的56°S处冷核（气旋）涡旋（cold-core (cyclonic) eddy）。本次调查的核心目标为获取南大洋不同类型开阔大洋涡旋的水文与生物地球化学剖面数据，以支撑其热量、盐度与营养盐特征的对比研究与数值模拟，同时揭示暖核涡旋自极锋向南迁移进入南大洋过程中上述属性的演变规律。本次航次共在西南印度洋中脊以南海域布设了18个温盐深仪（CTD，Conductivity-Temperature-Depth）测站，沿三条断面开展观测，这些断面覆盖了航前通过卫星高度计数据识别出的多个中尺度涡旋特征。