A key area of research for the Bluewater and Climate Node is discovering and understanding the links between ocean and climate variability, marine chemical cycling and ecosystem structure and function (e.g. biodiversity) from multi-decadal through to monthly timescales.

The two major poleward flowing boundary currents around Australia, the East Australian Current and the Leeuwin Current, play a vital role in regulating the productivity, abundance, and distribution of marine pelagic and benthic ecosystems.  These warm boundary currents are generally nutrient poor, leading to low oceanic productivity.  However, nutrient enrichment processes including cold-core eddies, shelf-edge upwelling, and topographic upwelling near capes, cause localised peaks in productivity.  These productivity hotspots are critical to supporting the diverse fisheries and populations of seabirds, marine mammals and sea turtles in the region.  Key knowledge gaps include understanding how lower trophic levels will respond to climate change, how this will influence the higher trophic levels, and understanding the direct impacts of climate change on the distribution and abundance of higher trophic levels.  Another important area around Australia is the Southern Ocean.  The area supports a large aggregation of top predators and biota of the region are uniquely adapted to the extreme environments in which they exist, and thus vulnerable to shifts in climate.  Understanding the response of marine biota to climate forcing is vital both for climate and for management of marine resources.

Key Science Questions

• How does the large scale circulation control the links between the physical, chemical and biological environment?
• What controls the temporal variation in biogeochemical fluxes of the ocean and how will they respond to climate variability?
• Are we able to determine the spatial and temporal variability of the main biological resources?
• What is the relationship of rapid mixed-layer dynamics in the Southern Ocean on plankton production and carbon transports?
• How do the different trophic levels respond to climate variability and climate change?
• Can we determine a more complete understanding of trophic connectivity and how it might be altered under a changing climate?
• What are the affects of climate change on;
  • The structure and functioning (energy, water and nutrient cycling) of ecosystems
  • The processes and phases of life cycles
• What are the most vulnerable regions and species (either particularly sensitive or unable to adapt) to changing environmental factors?
• Can we determine indices for assessing ecosystem health and for fisheries management?
• How do the changes in boundary currents (EAC and LC) influence ecosystem productivity?
• How do cross-shelf exchange processes (boundary currents and shelf regions) influence coastal productivity and ecosystem connectivity?
• How do changes in ocean acidification influence key vulnerable ecosystems such as the Southern Ocean, coral reefs and the continental shelves?