An acoustic doppler velocimeter to study zooplankton-turbulence interactions

用于研究浮游动物与湍流相互作用的声学多普勒测速仪

• 批准号: 344728-2007
• 负责人: Bourgault, Daniel
• 金额: $ 1.33万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments - Category 1 (<$150,000)
• 财政年份: 2006
• 资助国家: 加拿大
• 起止时间: 2006-01-01 至 2007-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=325745
• 关键词: acoustic; doppler; velocimeter; study; zooplankton

Our long-term research goal is to determine the role of zooplankton in generating ocean turbulence. In 1966, the famous oceanographer Walter Munk concluded, based on order of magnitude calculations, that biologically-driven mixing was negligible compared to physically-driven mixing such as that generated by currents, internal tides and convection. Surprisingly, recent discoveries published in 2006 based on field measurements suggest that swarms or schools of zooplankton may be an important source of ocean turbulence during daily vertical migration. Trying to understand how biologically-driven mixing works is complicated by the fact that zooplankton are small organisms (< 2 cm) that may disturb the flow and cause turbulence at very small scales. Therefore, to obtain quantitative information on zooplankton-turbulence interactions simultaneous observations of zooplankton and small-scale flow are required. Fortunately, instruments exist for measuring such small-scale biological (zooplankton) and physical (smallest turbulent eddies) features. Video Plankton Recorders (VPR) can sample individual zooplankton and Acoustic Doppler Velocimeters (ADV) can measure accurately the three-dimensional currents within a ~ 1 cm^3 sampling volume. Our goal is to configure these two specialized intruments in order to obtain simulataneous, fine-scale measurements of zooplankton and turbulence. We already have access to a VPR that is deployed and operational at the Bonne Bay Observatory. In this proposal we seek support from NSERC to acquire an ADV that we wish to coordinate with the VPR as an instrument package to study naturally-occuring zooplankton-driven turbulence.

我们的长期研究目标是确定浮游动物在产生海洋湍流中的作用。1966年，著名海洋学家沃尔特·蒙克根据数量级计算得出结论，与洋流、内潮和对流等物理驱动的混合相比，生物驱动的混合微不足道。令人惊讶的是，2006年发表的基于现场测量的最新发现表明，在日常垂直迁徙过程中，成群或成群的浮游动物可能是海洋湍流的重要来源。浮游动物是一种小型生物，可能会在很小的尺度上扰乱水流并造成湍流，这一事实让我们很难理解生物驱动的混合是如何起作用的。因此，为了获得浮游动物-湍流相互作用的定量信息，需要对浮游动物和小尺度流动进行同步观测。幸运的是，已经有仪器可以测量这种小规模的生物(浮游动物)和物理(最小的湍流涡流)特征。浮游生物录像机(VPR)可以对浮游动物个体进行采样，声学多普勒测速仪(ADV)可以在1 cm~3的采样量范围内精确测量三维水流。我们的目标是配置这两台专门的仪器，以便同时获得浮游动物和湍流的精细测量。我们已经可以使用Bonne Bay天文台部署和运行的VPR。在这项建议中，我们寻求NSERC的支持，以获得一个我们希望与VPR协调的ADV，作为研究自然发生的浮游动物驱动的湍流的仪器包。