The Bluewater and Climate Node has the task of determining a comprehensive, integrated and multi-disciplinary set of observations designed to address some of the major science questions relating to Australia’s oceanic environment.
Managing a Variable and Uncertain Climate
The strong variability characteristic of Australia’s climate is driven by interaction between the atmosphere and the surrounding oceans, in particular the western Pacific, eastern Indian and Southern Oceans. Australia’s heavy reliance on commodity exports and large agricultural sector means we have a climate sensitive economy. For example, many areas of the economy are adversely impacted by climate variability with a $10B (1.6%) decrease in GDP associated with droughts, while in regional Australia the impact is much larger at 10% (Adams et al., 2002).
Improved climate prediction on seasonal timescales can help mitigate these impacts in the natural terrestrial environment, agricultural sector, water management and health and disaster mitigation systems (e.g. bushfire risk). The science of seasonal climate forecasting relies on timely and accurate ocean data streams and enhanced understanding of upper ocean processes and atmosphere/ocean coupling.
Rising Sea Levels, Warming and Aridification under Climate Change
As a continent located largely in the latitudes of the ‘desert, the most populous and agriculturally productive regions of the Australian continent are likely to experience substantial warming and drying over the next decades due to anthropogenic climate change. Australia is also a coastal nation: 86% of the population lives within 50 km of the coast along with much of our infrastructure. Australians are thus highly vulnerable to sea level rise.
Australian policy makers and the public require more thorough and timely global and regional assessments of ongoing changes in our climate, oceans, ice-sheets and terrestrial systems. Improved projections are also needed to underpin adaption. Unresolved natural decadal variability and poorly modelled ocean processes are a challenge, and an adaptive approach to managing risk guided by timely observations of how the system is responding to changes in forcing is important.
Thus, monitoring is required for
- early detection of large or rapid shifts in the climate and marine ecosystems
- developing climate change mitigation and adaptation policies
- tracking the effectiveness of national and international policy interventions
Stewardship and Conservation of Biodiversity
Under the United Nations Convention on the Law of the Sea (UNCLOS), Australia has one of the largest marine jurisdictional zones in the world. This zone comprises about 16 million km2, excluding Antarctica, is double the Australian landmass and includes some 4.4% of the global ocean area. Australia’s marine area includes about 12,000 islands and some of these islands have an important role in extending Australia’s EEZ, and hence our marine responsibilities.
Australia has a long history of leadership in Antarctica and the Southern Ocean, and its influence in the Antarctic Treaty system is to a large degree founded on the quality of its science in Antarctica and the Southern Ocean. Sustained observations of the Australian sector of the Southern Ocean are one means of demonstrating the physical presence and stewardship needed to support Australia’s sovereignty in the region. Fisheries in the Southern Ocean are managed under the Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR), with Australia playing a key role in research and southern ocean fisheries management. Australia plays a leading role in the International Whaling Commission’s (IWC) assessment of Southern Ocean whale stocks and in managing these stocks within the IWC framework.
Australia's ocean domain includes all five of the world's ocean temperature zones - tropical, subtropical, temperate, subpolar and polar, with habitats that contain a wealth of fauna and flora, most of which are unique to Australia.
Sustainable Use of Marine Resources
Australian policy requires that we maintain healthy and properly functioning ecosystems, and that this is best achieved by managing the marine ecosystem in an integrated way. Data that quantify the response of ocean physics, chemistry and biology to climate variability is needed as part of this integrated ecosystem based management. Examples include ecosystem based fisheries management (EBFM) and in the planning for Bluewater Marine Protected Areas (MPAs).
Marine ecosystems also provide major economic and social values through commercial and recreational fishing and marine aquaculture. The Australian Fishing Zone is the third largest in the world, covering nearly nine million square kilometres, with its Commonwealth fisheries worth ~ $320 million in production value alone. Climate change is expected to have dramatic impacts on fisheries and aquaculture through changes in temperature, ocean currents, winds, nutrient supply, rainfall, ocean chemistry, and extreme weather conditions.
Defence and Security
Australia's defence and security rely on the ability to operate in the maritime environment of the Australian region, and specifically to defend the air and sea approaches to Australia. The physical oceanography of our region is extraordinarily complex: the highly dynamic East Australian Current and Leeuwin Current dominate the east and west coasts, respectively; the poorly-understood Indonesian Throughflow affects the waters to our north; extreme tidal variation occurs in the Timor and Arafura Seas, and on the North West Shelf; upwelling events take place in some coastal regions; and internal waves dominate the physical oceanography of the North West Shelf and the Coral Sea. The Australian Government's Defence White Paper 2009 (Defending Australia in the Asia Pacific Century: Force 2030 ) lays out a vision for a large and capable submarine force, and greatly improved Anti-Submarine Warfare (ASW) capability for the Royal Australian Navy (RAN). A deep understanding of the oceanography of the Australian region (ranging from physical circulation, to production of sedimentary particle clouds, to biological sources of noise), and an ability to monitor and predict them, will be required to ensure the maximum effectiveness of these new defence capabilities.