Australia's boundary Currents: Altimetry, In-Situ and Model Estimates.
Griffin, David; Cahill, Madeleine; Oke, Peter
CSIRO Marine and Atmospheric Research, AUSTRALIA
Australia has strong boundary currents on both its south-western and south-eastern margins, as well as weaker flows elsewhere along the upper continental slope. Knowing and understanding the variability of these currents is of principle importance for a host of reasons. All levels of the ecosystem are impacted by these currents, as are many of man's maritime operations. Estimating the strength of the boundary currents from altimetry is a challenge because of various errors associated with the proximity to land. In this talk we review progress made recently in this direction using the recently-available re-processed Envisat data, including the special 'coastal altimetry' high- resolution Envisat data set produced by the ESA-sponsored CoastAlt project. The altimetric estimates are compared with several new Acoustic Doppler Current Profiler and High Frequency Radar estimates of boundary current velocities acquired around Australia by the Australian Integrated Marine Observing System, and also with velocity estimates made by hydrodynamic models. The combination of these three techniques yields new insights into the behaviour of these currents.