The south east region supports approximately 60% of Australia’s population (Gergis and Ashcroft, 2013), with the communities being socially and economically diverse, with environmental sustainability, biodiversity and the use of resources to secure future sustainable economic benefits highly valued by the community.
The two largest marine based industries in the SEA-IMOS region are marine based tourism and offshore oil and gas industries. These industries account for ~ 80% of the region’s income generation, with the remaining 20% including activities such as aquaculture, commercial fishing, ports, ship building and shipping activities.
In addition, the South-east Commonwealth Marine Reserves Network has been established to protect examples of the biodiversity and seafloor features of the Commonwealth waters of the South-east Region. The network stretches from the far south coast of New South Wales, around Tasmania and Victoria and west to Kangaroo Island off South Australia, covering an area of 388 464 km2. Between Tasmania and Victoria there are also a number of state managed marine protected areas (MPAs) which also contribute to the protection of marine biodiversity, species representation and uniqueness. These state reserves complement the national network of Commonwealth MPAs by being representative of the inshore habitats (inside 3 nm) of the states coastal waters.
The Australian continent is highly sensitive to ocean-influenced climate and weather, and regularly experiences drought, flood, tropical cyclones and other extreme events. Due to our reliance on commodity exports and our large agricultural sector, Australia’s economy is highly sensitive to climate. The South East marine region has been identified as being extremely vulnerable to climate change. The effects of climate change to marine systems will not only affect biodiversity and ecosystem health, but also most of the marine industries and the security of coastal infrastructure.
Southern Australia has experienced some of the fastest increases in ocean temperatures globally. The strengthening of the East Australian Current has seen the sea surface temperatures rise by ~2 °C since 1925. These warming temperatures are already impacting the marine ecosystems in the region, with the arrival of a number of species with warm water affinity documented off the coast of Tasmania and east coast Victoria. A potential increase in ocean acidification will also impact marine biodiversity in particular by calcifying species such as reef building corals, commercially important shellfish and a range of phytoplankton and zooplankton at risk from declining pH.
In addition, rising sea temperatures can also alter ocean currents, raise sea levels, and increase the occurrence and severity of storms. Changes in the frequency and magnitude of extreme sea level events, such as storm surges combined with higher mean sea level will increase the risk of coastal inundation. A more thorough and timely assessment of ongoing changes in our climate, oceans, and terrestrial ecosystems is imminently required.
An improved projection of the state of climate, oceans and effect to ecosystems is needed to underpin adaptation and possible mitigation. Even with truly quantitative predictions, an adaptive approach to mitigation/adaptation policy is needed, guided by timely observations of how the system is responding to changes that are being forced up it. Monitoring is therefore required for:
- The early detection of large or rapid shifts in the climate and marine ecosystems
- Information needed to develop climate change mitigation and adaptation policies
- Tracking the effectiveness of national and international actions to control climate change, including Australia’s management of its carbon budget and as a contribution to the global carbon budget
With ~ 85% of the nation’s population living within 50 km of the ocean, understanding our oceans is a matter of national importance for current and future generations of all Australians.