Hobart

Seminar Abstract

Friday 22 August 2008, 11.30am (Tas time)
CSIRO Auditorium, Hobart

George Cresswell
Honorary Fellow
CSIRO Marine and Atmospheric Research

Ocean currents at a year-long continental shelf mooring 35 km NNW of Rottnest Island

Following an historical introduction, we dissect a one-year record (Nov 2000 – Nov 2001) from an ADCP (Acoustic Doppler Current Profiler) moored near the bottom at the 71 m isobath NNW of Rottnest Island, WA. The instrument recorded the currents hourly in 4 m depth bins from 17-65 m depth.

Wind stress, sea level and satellite images were entrained into the interpretation of the record.

The record carries the fingerprints of the usual suspects: The Leeuwin and Capes Currents; wind forcing by passing weather systems; inertial waves from the sea-land breeze cycle; shear; a meander and an eddy of the Leeuwin Current; cross-shelf flows; as well as a wave-like phenomenon with a time scale of 15-45 hours that produced anticyclonic loops up to 10 km across in the Leeuwin Current flow (as seen in progressive vector diagrams).

The Capes Current reached 0.9 ms^-1 at the surface; the Leeuwin Current was strongest near the bottom – maybe 0.6 ms^-1 – where it persistently angled offshore (the same thing seemed to occur at Lucie mooring D2).

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Location:
CSIRO = Marine Laboratories Auditorium, Castray Esplanade, Hobart

For further information, or to schedule a seminar, contact:
To schedule a seminar, contact:
Bernadette Sloyan, (Oceanographic seminars) CSIRO Marine and Atmospheric Research (03) 6232 5152
Thomas Kunz, (Biological seminars) CSIRO Marine and Atmospheric Research
(03) 6232 5076
Natalie Dowling, (Fisheries Modelling) CSIRO Marine and Atmospheric Research
(03) 6232 5148
Jillian Enraght-Moony, (seminar administrator) CSIRO Marine and Atmospheric Research (03) 6232 5320
Communications Manager, Antarctic Climate and Ecosystems CRC (03) 6226 2265
Margaret Hazelwood, Institute of Antarctic and Southern Ocean Studies (IASOS) University of Tasmania (03) 6226 2971

Last updated 21/07/09