Exchange Flow Variability between Hypersaline Shark Bay and the Ocean

A steady, near-bed dense water outflow from Shark Bay’s northern Geographe Channel was observed for the first time, persisting through all tidal stages and exhibiting velocities 2–3 times stronger than previously recorded outflows in Naturaliste Channel. This outflow, driven by longitudinal density gradients, proved more resistant to tidal mixing, with turbulence peaking during flow reversals. The study identified tidal seabed flow as the primary source of turbulence, using bottom current speed cubed (|Ub³|) as a proxy for predicting dense water outflows. The Geographe Channel’s orientation and depth along the main density gradient axis explained its predominant outflow role, suggesting potential impacts on marine life recruitment, including commercially fished scallops and prawns.

Hetzel, Y., Pattiaratchi, C., & Mihanović, H. (2018). Exchange Flow Variability between Hypersaline Shark Bay and the Ocean. Journal of Marine Science and Engineering, 6(2), 65. https://doi.org/10.3390/jmse6020065