Physical oceanography during ROV dive PS118_9-10

During a seabed observation dive (depth 400 m) in the western Weddell Sea near the tip of the Antarctic Peninsula, underwater video recordings of the benthos and oceanographic CTD data of the surrounding area were recorded. A modified Ocean Module V8Sii ROV (Remotely Operated Vehicle) was launched from RV Polarstern and surveyed a portion of the seabed with a maximum extent of 110 by 35 m. The device was equipped with two cameras of different resolutions: an HD camera (Kongsberg oe14-502, 720p50) and a 4k camera (SubC Imaging Mk6, 2160p25). Environmental data was recorded with a CTD (SeaBird 19plusV2), which included sensors for chlorophyll a (Wetlabs FLRT), oxygen (SEB 43), pH (SEB 18) and PAR (Biospherical), in addition to standard instruments for conductivity, temperature and pressure. The ROV's position was recorded using iXblue's GAPS USBL (Ultra-Short Baseline). In addition, the ROV's path across the seabed was recorded using a DVL from RD instruments (see metadata). The global orientation with respect to magnetic north was determined with an internal IMU device.
The video footage gives a comprehensive impression of the unique local cold-water ecology of the seafloor. To determine the true image scale on the high-resolution footage, a series of reference lasers were used to indicate 10 cm on the recorded objects. An additional altimeter (Tritech) provided acoustically measured distances to the HD camera (see metadata).

在南极半岛尖端附近的威德尔海西部开展400米水深海底观测潜次期间，采集了底栖生物（benthos）的水下视频录像与周边海域的海洋学温盐深仪（CTD）数据。改装版Ocean Module V8Sii型遥控水下机器人（ROV）从极星号（RV Polarstern）科考船布放，对一片最大范围为110×35米的海底区域开展了探测作业。该机器人搭载两台不同分辨率的摄像机：一台高清（HD）摄像机（Kongsberg oe14-502，720p50）与一台4K摄像机（SubC Imaging Mk6，2160p25）。环境数据由SeaBird 19plusV2型温盐深仪采集，除配备电导率、温度与压力的标准传感器外，还搭载了叶绿素a（chlorophyll a）传感器（Wetlabs FLRT）、溶解氧传感器（SEB 43）、pH传感器（SEB 18）以及光合有效辐射（PAR）传感器（Biospherical）。该ROV的位置通过iXblue公司的GAPS超短基线定位系统（USBL）进行记录。此外，该ROV的海底航行轨迹通过RD Instruments公司的多普勒测速仪（DVL）记录（详见元数据）。通过内置的惯性测量单元（IMU）确定其相对于磁北的全局方位。本次采集的视频素材全面展现了该海域海底独特的冷水生态系统风貌。为确定高分辨率视频画面的真实比例尺，研究团队通过一系列参考激光在录制对象上标注出10厘米的长度基准。另外搭载的Tritech高度计可通过声学方式测量与高清摄像机之间的距离（详见元数据）。