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Marine and Freshwater Research Marine and Freshwater Research Society
Advances in the aquatic sciences
RESEARCH ARTICLE

Modelling the physical oceanography of the D'Entrecasteaux Channel and the Huon Estuary, south-eastern Tasmania

M. Herzfeld A C , J. Andrewartha A and P. Sakov B
+ Author Affiliations
- Author Affiliations

A CSIRO Division of Marine and Atmospheric Research and Aquafin CRC, GPO Box 1538, Hobart, Tas. 7001, Australia.

B Nansen Environmental and Remote Sensing Center, University of Bergen, Norway.

C Corresponding author. Email: mike.herzfeld@csiro.au

Marine and Freshwater Research 61(5) 568-586 https://doi.org/10.1071/MF09134
Submitted: 4 June 2009  Accepted: 4 November 2009   Published: 28 May 2010

Abstract

A three-dimensional primitive-equation hydrodynamic model was applied to the Huon Estuary and D'Entrecasteaux Channel in south-eastern Tasmania to characterise the physical oceanography of the coupled system. Model results verify that the Huon Estuary behaves as a salt-wedge estuary, and can be considered the driver for residual circulation for the system; the bottom water enters the southern channel and is directed up-estuary in the form of a salt wedge, to be entrained into the surface layer along its length, whereas freshwater downstream flow is returned to the channel. The D'Entrecasteaux Channel behaves as a ROFI (Regions of Freshwater Influence) regime, where buoyancy owing to the freshwater inflow stabilises the water column, in competition with mixing processes. The ROFI is influenced by rotation, resulting in a flow predominantly directed northward in the channel, with only a small percentage exiting the southern boundary under the influence of northerly winds. The connectivity of the region is largely influenced by the residual circulation, where the northern channel exhibits poor connectivity with the rest of the system, whereas the southern channel and Huon are relatively well connected throughout. Flushing analysis and particle tracking show the flushing time for the whole region to be ∼20–26 days.

Additional keywords: circulation, modelling, numerical, ocean.


Acknowledgements

This work was conducted as part of the Aquafin CRC ‘System-wide environmental issues for salmonid aquaculture’ project 2001/047. Funding from the CRC, FRDC and Tasmanian Salmonid Growers Association is gratefully acknowledged as are the contributions from colleagues from CSIRO Marine and Atmospheric Research and Tasmanian Aquaculture and Fisheries Institute.


References

Bedford, K. W. , and Lee, J. (1994). Near-bottom sediment response to combined wave-current conditions, Mobile Bay, Gulf of Mexico. Journal of Geophysical Research 99, 16 161–16 177.
Crossref | GoogleScholarGoogle Scholar | Bobbi C. (1998). Water quality of rivers in the Huon catchment. Report series WRA 98/01. Tasmanian Department of Primary Industry and Fisheries, Hobart.

Burchard H., Bolding K., and Villarreal M. R. (1999). GOTM, a general ocean turbulence model. Theory implementation and test cases. Technical report EUR 18745EN, European Commission.

Burgess S., Roberts S., Shanton A., Chen C., Smith H., and Gorman J. (1993). Environmental quality of the lower Huon River catchment. Unpublished report. Centre for Environmental Studies, University of Tasmania, Hobart, Tas.

Butler E. (2006). The tail of two rivers in Tasmania: the Derwent and Huon estuaries. In ‘Handbook of Environmental Chemistry. Vol. 5, Part H’. pp. 1–49. (Springer-Verlag: Berlin.)

Butler E. C. V., Parslow J. P., Volkman J. K., Blackburn S. I., Morgan P., et al. (2000). Huon Estuary Study – environmental research for integrated catchment management and aquaculture. Final report to Fisheries Research and Development Corporation. Project no. 96/284. CSIRO Division of Marine Research. Marine Laboratories, Hobart, Tas.

Cartwright, D. E. , and Ray, R. D. (1990). Oceanic tides from Geosat altimetry. Journal of Geophysical Research 95, 3069–3090.
Crossref | GoogleScholarGoogle Scholar | Dyer K. R. (1997). ‘Estuaries: A Physical Introduction.’ (John Wiley: Chichester, UK.)

Dyke P. P. G. (2001). ‘Coastal and Shelf Sea Modelling.’ Kluwer International Series: Topics in Environmental Fluid Mechanics. (Kluwer Academic Publisher: London.)

Fitzpatrick, J. J. (2009). Assessing skill of estuarine and coastal eutrophication models for water quality managers. Journal of Marine Systems 76, 195–211.
Crossref | GoogleScholarGoogle Scholar | Gallagher S. (1996). Huon Catchment Healthy Rivers Project: water quality assessment report. Prepared for National Landcare Program, Huon Valley Council and Tasmanian Department of Primary Industry and Fisheries, Hobart, Tas.

Herzfeld, M. (2006). An alternative coordinate system for solving finite difference ocean models. Ocean Modelling 14, 174–196.
Crossref | GoogleScholarGoogle Scholar | Herzfeld M., Parslow J., Sakov P., and Andrewartha J. R. (2005). Numerical hydrodynamic modelling of the D'Entrecasteaux Channel and Huon Estuary. Project 4.2, FRDC Project No. 2001/097, Aquafin CRC technical report, Hobart.

Huthnance, J. M. (1997). The PROFILE project: an overview. Journal of Marine Systems 12, 249–261.
Crossref | GoogleScholarGoogle Scholar | Macleod C., Bissett A., Burke C., Forbes S., Holdsworth D., Nichols P., Revill A., and Volkman J. (2004). Development of novel methods for the assessment of sediment condition and determination of management protocols for sustainable finfish cage aquaculture operations. Project 4.1, Aquafin CRC and FRDC, Hobart.

Martin, J. (1988). Application of a two-dimensional water quality model. Journal of Environmental Engineering 114, 317–336.
Crossref | GoogleScholarGoogle Scholar | CAS | Parslow J. S., Herzfeld M., Hunter J. R., Andrewartha J. R., Sakov P. V., and Waring J. R. (2001). Mathematical modelling of the dispersal and fate of CES discharge from the Boyer Mill in the upper Derwent Estuary. Results of Part B. Final report, CSIRO Division of Marine Research, Hobart, Tas.

Poodle, T. (1986). Freshwater inflows into the Firth of Clyde. Royal Society of Edinburgh Section B 90, 55–66.
Thompson P. A., Bonham P., Wilcox S., and Crawford C. (2005). Baseline environmental data for the D'Entrecasteaux Channel. Aquafin CRC project 4.2. FRDC project no. 2001/097, Hobart.

Uncles, R. J. (2002). Estuarine physical processes research: some recent studies and progress. Estuarine, Coastal and Shelf Science 55, 829–856.
Crossref | GoogleScholarGoogle Scholar | Volkman J. K., Parslow J. S., Thompson P. A., Herzfeld M., Wild-Allen K., et al. (2006). System-wide environmental issues for sustainable salmonid aquaculture: interim report. Aquafin CRC project 4.2. FRDC project no. 2001/097, Hobart.

Walker S. J. (1997). Hydrodynamic models of Port Phillip Bay. CSIRO Port Phillip Bay Environment Study technical report no. 38, Melbourne.

Wallace G. (1998). Modelling surface salinity in the Huon Estuary. B.Sc.(Honours). School of Mathematics and Physics, University of Tasmania, Hobart, Tas.

Warner, J. C. , Geyer, W. R. , and Lerczak, J. A. (2005). Numerical modelling of an estuary: a comprehensive skill assessment. Journal of Geophysical Research 110, C05001.
Crossref | GoogleScholarGoogle Scholar | Woodward I. O., Gallagher J. B., Rushton M. J., Machin P. J., and Mihalenko S. (1992). Salmon farming and the environment of the Huon Estuary, Tasmania. Sea Fisheries Division, technical report 45. Department of Primary Industry, Fisheries and Energy, Hobart, Tas.

Zillman J. W. (1972). ‘A Study of Some Aspects of the Radiation and Heat Budgets of the Southern Hemisphere Oceans.’ Bureau of Meteorology, Meteorological study no. 26. (Australian Government Publication Service: Canberra.)