Abstract
Understanding the properties of surface dispersion within estuaries provides an insight into important environmental processes that govern pollutant transport and water quality issues. Simultaneous field observation of dispersion measured by clusters of GPS-tracked drifters were used to examine the dispersion behaviours at the ends of an estuary with two tidal inlets. The field study was conducted in Pumicestone Passage- an estuary which extends over 45 km from the south to the northern end and covers ~60 km2 with a width >500 m and depth 2 - 3 m mid-estuary. We examine the difference in the dynamics of the two inlets through applying pair-particle statistics, a metric closely tied to mixing processes. Average diffusivity values indicated that larger diffusivity exists at the southern inlet, with values of KNs=0.244 m2s-1, KNn=0.146 m2s-1 and KSs=0.831 m2s-1, KSn=0.878 m2s-1, for the northern and southern inlets, respectively. Additionally power relations were developed for diffusivities with separation scales less than 5 m.