Numerical Study of the Brisbane River Plume in Moreton Bay, Australia

Abstract

Coastal rivers that discharge freshwater, with sediment and nutrients, into the ocean often generate a buoyant river plume in the vicinity of the river mouth. The river plume, driven by river floods, has become a significant environmental issue, which may be increasing in occurrence and severity as a consequence of climate change. The excess runoff created by floods has the capacity to carry a large amount of sediment and contaminants from land-based human activities into the coastal and shelf waters. The purpose of this research was to examine the dynamic and transport characteristics of the Brisbane River plume using a numerical model. It also sought to answer the following questions: 1) What is the seasonal behaviour of the Brisbane River plume, particularly during flood seasons, and 2) What are the impacts of external forces acting on the Brisbane River plume? It is anticipated that the knowledge gained from this research will promote a better understanding of the Brisbane River plume behaviour in Moreton Bay.