Continental Shelf Processes

 

How will the key science questions be addressed?

 

Examine the coastal wind and wave climate in driving nearshore currents and the northward sediment transport.

The NSW-IMOS Node will investigate the utility of HF Radar to provide directional wave spectra over a large spatial area, as opposed to the current 7 point records at buoys along the coast.  The WERA HF radar array has the ability to measure wave frequency period and directional wave spectra across the entire radar domain.  A deployment scheduled for Coffs Harbour is designed to overlap the domain of the Coffs Harbour waverider buoy to allow for an assessment of the accuracy of the wave measurements derived from the HF radar.  As an additional contribution to IMOS it is anticipated that we will trial a WAMOS wave measurement system which has the ability to provide directional wave spectra in high resolution in the near shore zone.  This system also has the potential to provide measurements of sea bed topography which can be used in the enhancement of wave models.

Quantify the biogeochemical cycling of carbon (nutrients and phytoplankton composition).

The water quality monitor at the Port Hacking NRS currently provides estimates of turbidity and fluorescence at one depth, which in combination with dissolved nutrients and oxygen, provides data to understand biogeochemical cycling.  In co-ordination with SRS nutrient and plankton observations, and SOOP carbon measurements, gliders quantify the biogeochemical state of the water column.  Oxygen, coloured dissolved organic matter (CDOM) and fluorescence indicate the state of carbon in the system, and hence can aid calculations of carbon fluxes.  The observations by glider deployments over 4 years will provide an archive of vertical profiles of oxygen, CDOM and even fluorescence that dwarf the number presently available.

Determine the transport and dispersal of passive particles (e.g. larvae, eggs, spores) and the degree of along coast connectivity and trophic linkages.

The Solitary Islands Marine Park (SIMP) is both a state and federal marine reserve and it is in this region that we have focused our upstream East Australian Current (EAC) observations.  The combination of HF Radar giving spatial coverage of the flow patterns at the surface and the moorings giving resolution throughout the water column will help answer the question of the dispersion of passive particles in and around SIMP.  AATAMS lines are also focused through SIMP which will provide insight into the nature of the connectivity between fish populations in the region.  These data will inform modelling studies of connectivity along the NSW coastline and both within and among marine reserves.