REGIONAL OCEAN FORECASTING

An important issue facing many offshore operators and contractors is an awareness of the existing and forecast risks associated with the subsea oceanic environment. For example internal waves or deep sea oceanic current patterns may influence the potential for VIV (Vortex-Induced-Vibrations) of risers, thus risking the integrity and safety of the operation or may experience significant operational downtime.

For the Australian North West Shelf, ONS has developed a regional ocean forecasting system based on the ROMS ocean model. The spatial scale of the model is 1/20th degree (~ 5km) and producing full three dimensional ocean forecasts out to 5-7 days at a 0.5hr temporal resolution.

Open boundaries from the model are sourced from the global model, HYCOM. Atmospheric heat fluxes, winds and sea level pressures are provided by the global GFS forecasting system.

Typical output from the model includes:-

Tidal elevation (internal waves are resolved)
Sea water temperature
Salinity
Water density
3D ocean currents

For site specific applications (upon request), full profile point data may be exported, analyzed and reformatted into a presentable form. As the data is fully three dimensional, it may be used to assess the dispersion from point sources including oil spills and other contaminants.

The animations below show the forecast water temperature/salinity and current speed for a horizontal slice 10m below MSL