Turbulence Measurements from Compliant Moorings. Part I: Motion Characterization

Levi Kilcher, Samuel Harding, Jim Thomson

Research output: Contribution to journalArticlepeer-review

12 Scopus Citations


High-fidelity measurements of turbulence in the ocean have long been challenging to collect, in particular in the middle of the water column. In response, a measurement technique has been developed to deploy an acoustic Doppler velocimeter (ADV) to midwater locations on a compliant mooring. A variety of instrumentation platforms have been deployed as part of this work with a range of dynamic motion characteristics. The platforms discussed herein include the streamlined StableMoor buoy (SMB), the Tidal Turbulence Mooring (TTM) system based on a conventional 0.9-m spherical buoy, and a 100-lb sounding weight suspended from the stern of a research vessel. The ADV head motion is computed from inertial motion sensors integrated into an ADV, and the spectra of these signals are investigated to quantify the motion of each platform. The SMB with a single ADV head mounted on the nose provided the most stable platform for the measurement of tidal turbulence in the inertial subrange for flow speeds exceeding 1.0 m s-1. The modification of the SMB with a transverse wing configuration for multiple ADVs showed a similar frequency response to the nose configuration in the horizontal plane but with large contamination in the vertical direction as a result of platform roll. While the ADV motion on the TTM was significant in the horizontal directions, the vertical motion of this configuration was the most stable of all configurations tested. The sounding weight measurements showed the greatest motion at the ADV head but are likely to be influenced by both prop-wash and vessel motion.

Original languageAmerican English
Pages (from-to)1235-1247
Number of pages13
JournalJournal of Atmospheric and Oceanic Technology
Issue number6
StatePublished - 1 Jun 2017

Bibliographical note

Publisher Copyright:
© 2017 American Meteorological Society.

NREL Publication Number

  • NREL/JA-5000-68974


  • Buoy observations
  • In situ oceanic observations
  • Instrumentation/sensors


Dive into the research topics of 'Turbulence Measurements from Compliant Moorings. Part I: Motion Characterization'. Together they form a unique fingerprint.

Cite this