1 / 14

Moorings and Current Meters

Moorings and Current Meters. Ellen Martinsek EPS 131 December 14, 2005. Outline. Moorings Purpose Deployment & Recovery Specific Projects Current Meters Different Methods of Measuring Current Acoustic Doppler Measurements Applications. Moorings.

chesmu
Download Presentation

Moorings and Current Meters

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Moorings and Current Meters Ellen Martinsek EPS 131 December 14, 2005

  2. Outline • Moorings • Purpose • Deployment & Recovery • Specific Projects • Current Meters • Different Methods of Measuring Current • Acoustic Doppler Measurements • Applications

  3. Moorings Connection between water surface and instrumentation in the ocean below the surface

  4. Deployment & Recovery • Difficult since the mooring cable breaks if moved too quickly • Need to keep instruments and data safe

  5. Back to WHOI Sub-Surface Mooring Operations Group: over 90% instrument and data recovery

  6. North Pole Environmental Observatory • First year-round mooring at the North Pole retrieved in April 2002 • Purpose: to see how the Arctic Ocean influences global climate Retrieving a mooring that has been collecting oceanographic data from the Arctic Ocean for a year at the NSF’s North Pole Environmental Observatory Photo Credit: Peter West/National Science Foundation

  7. Monterey Ocean Observing System (MOOS) test mooring

  8. Power source (on float) float “S” bend instruments MOOS test mooring • Biggest engineering problem: creating a cable that can stay intact! • 11 days after the first deployment (December 3, 2002) the cable snapped  had to redesign it before finally redeploying on April 23, 2004.

  9. Measuring Current … • Mechanical current meters • Electromagnetic current meters • Acoustic Travel Time current meters • Acoustic Doppler measurements

  10. Acoustic Doppler measurements • Why sound is good to use • The Doppler Effect • Back Scatter Sonar – How It Works

  11. RDCP 600 (by Aanderaa) – 600kHz self-recording Doppler Current Profiler Acoustic Doppler Current Profiler (ADCP) Constant frequency pings transmitted Ricochet off suspended particles and reflect back Calculate speed of particle and surrounding water using Doppler shift

  12. Applications of Current Profiling • Climatic Research • Ports and Harbors • Fish Farming • Pollution Control

  13. Summary • Moorings serve as a connection between the water surface (which itself is connected via satellite to labs onshore) and instruments in the ocean • An important example of such instrumentation is the current profiler; in particular, the ADCP

  14. References • http://www.pmel.noaa.gov/vents/nemo1999/logbook/cal062399/ • http://www.mbari.org/news/homepage/2004/moosII.html • http://www.whoi.edu/institutes/occi/currenttopics/ct_oms_stationw.html • http://www.washington.edu/newsroom/news/2002archive/05-02archive/npfactsheet.html • http://www.antarctica.ac.uk/BAS_Science/programmes2000-2005/DYNAMOE/Moorings/index.html • http://walrus.wr.usgs.gov/mcgaw/depmoor.html • http://pulson.seos.uvic.ca/lecture.html • http://www.soc.soton.ac.uk/OED/gxg/Single_Point_CMs.pdf • http://www.aanderaa.com/docs/RDCP_600_D343.pdf • http://www.nsf.gov/od/lpa/news/03/ma0329.htm

More Related