Keynote Presentation 2024 Australian Marine Sciences Association Annual Meeting combined with NZMSS

The forcings influencing shoreline change along Australia’s low energy coastlines (#443)

Ruth Reef 1
  1. Monash University, Clayton, VIC, Australia

The global population in the low elevated coastal zone will exceed one billion by 2050. These regions are also subject to intensive agriculture and urbanisation. Thus, the impact of accelerating sea level rise and other changing geographical forcings on coastlines worldwide is of major societal concern. Changes to coastlines are not just a coastal erosion or flooding concern; seawater intrusion into coastal groundwater aquifers, biodiversity loss and impacts on human health are examples of the connection between coastal dynamics and broader Earth systems. I will present our latest computational and field research on how low energy coastlines operate, what is currently happening to Australia’s living coasts and what we might expect into the future. Our results demonstrate a role for mangroves in stabilising shorelines, but sea level rise response thresholds and macroclimatic and geomorphic forcings present tipping points that will impact both the future distribution of mangroves in Australia and the shape of our coastline. An ensemble of deep learning algorithms applied to 1,800,000 shoreline change observations identified that while knwon oceanographic and meteorological forcings and sediment supply are still the main drivers of coastal change, sea level rise is an emerging threat, especially along the western coastlines.