Marine ecosystems across turbidity gradients in arid tropical Australia could undergo regime shifts due to climate change

Ms Paula Cartwright1, Dr Peter Fearns2, Professor  Ryan  Lowe1, Dr Mick O’Leary1, Dr Nicola Browne2

1University Of Western Australia, Crawley, Australia, 2Curtin University, Bentley, Australia


Marine ecosystems in arid tropical north-western Australia are subjected to extreme climate events at the sub-decadal scale. As well as temperature anomalies and cyclones, turbidity events from both naturally occurring processes and anthropogenic disturbance can upset ecological balance and have long-lasting impacts at multiple spatial scales. Here we have analysed 18 years of calibrated ocean colour data to determine the primary met-ocean drivers of turbidity in the Exmouth Gulf, a region with high-value marine ecosystems. Further, we surveyed the Gulfs benthic habitats to assess where higher turbidity is impacting habitats and therefore, how intensification of turbidity drivers may worsen outcomes. We find that while increases in turbidity will be spatially variable, some habitats are likely to undergo permanent regime shifts under climate change predictions.


Paula is a final year PhD candidate at the University of Western Australia. Her multi-disciplinary research is helping to bridge the gap between science and marine management, by providing tools to analyse and understand the spatial ecology of important marine ecosystems. Paula’s research is currently focussed on the remote Exmouth Gulf in north Western Australia where she has performed an extensive long-term remote sensing analysis as well as two years of monthly in-situ water quality collection, designed to understand how climate change will affect the turbidity of the region. Prior to this her research was focussed in the Miri-Sibutu Coral Reef National Park, Borneo, where she developed a remote sensing turbidity algorithm and toolkit to allow the local Government marine park management authority to monitor flood plumes that threaten the regions coral reefs.