thumbnail

Aquatic Habitat Mapping with an Acoustic Doppler Current Profiler: Considerations for Data Quality

Open-File Report 2005-1163
By:  and 
https://doi.org/10.3133/ofr20051163

Links

Abstract

When mounted on a boat or other moving platform, acoustic Doppler current profilers (ADCPs) can be used to map a wide range of ecologically significant phenomena, including measures of fluid shear, turbulence, vorticity, and near-bed sediment transport. However, the instrument movement necessary for mapping applications can generate significant errors, many of which have not been inadequately described. This report focuses on the mechanisms by which moving-platform errors are generated, and quantifies their magnitudes under typical habitat-mapping conditions. The potential for velocity errors caused by mis-alignment of the instrument?s internal compass are widely recognized, but has not previously been quantified for moving instruments. Numerical analyses show that even relatively minor compass mis-alignments can produce significant velocity errors, depending on the ratio of absolute instrument velocity to the target velocity and on the relative directions of instrument and target motion. A maximum absolute instrument velocity of about 1 m/s is recommended for most mapping applications. Lower velocities are appropriate when making bed velocity measurements, an emerging application that makes use of ADCP bottom-tracking to measure the velocity of sediment particles at the bed. The mechanisms by which heterogeneities in the flow velocity field generate horizontal velocities errors are also quantified, and some basic limitations in the effectiveness of standard error-detection criteria for identifying these errors are described. Bed velocity measurements may be particularly vulnerable to errors caused by spatial variability in the sediment transport field.

Suggested Citation

Gaeuman, D., and Jacobson, R.B., 2005, Aquatic habitat mapping with an acoustic doppler current profiler: Considerations for data quality: U.S. Geological Survey Open-File Report 2005—1163, 20 p., https://doi.org/10.3133/ofr20051163.

ISSN: 2331-1258 (online)

ISSN: 0196-1497 (print)

Table of Contents

  • Abstract
  • Introduction
  • Purpose and Scope
  • General Methods for ADCP Habitat Assessment
  • General Aspects of ADCP Data Quality
  • Compass Errors
  • Errors Caused by Heterogeneous Velocity Field
  • Conclusions
  • Acknowledgments
  • Literature Cited
Publication type Report
Publication Subtype USGS Numbered Series
Title Aquatic habitat mapping with an acoustic doppler current profiler: Considerations for data quality
Series title Open-File Report
Series number 2005-1163
DOI 10.3133/ofr20051163
Edition Revised and reprinted 2005
Year Published 2005
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Columbia Environmental Research Center
Description iv, 20 p.
Online Only (Y/N) N
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
Additional publication details