Assoc Prof Tom Trull
Program Leader, Ocean Control of Carbon Dioxide

03 6226 2988 or 03 6232 5268
tom.trull@acecrc.org.au
The Ocean Control of CO2 program estimates CO2 uptake by the Southern Ocean and the risk and efficacy of proposals to enhance that uptake, for example by iron fertilisation.

OCEAN CONTROL OF CARBON DIOXIDE PROGRAM (CO2): OVERVIEW


CO2-01: Carbon Uptake in the Southern Ocean
This project will estimate the total and anthropogenic CO2 inventories in the Southern Ocean from measurements on two Australia-to-Antarctica hydrographic sections. This approach has been used to determine anthropogenic CO2 uptake between 1968 and 1996 and its extension over the next decade will test predicted slowing of CO2 and oxygen uptake by the ocean.

CO2-02: Carbon Export Processes
Deposition and storage of carbon dioxide in the deep ocean, where it can remain for centuries, is one of the main ways to effectively remove excess anthropogenic carbon dioxide from the atmosphere. In this project, we are deriving estimates of rates of transfer of particulate carbon between the ocean surface and the deep sea. We are identifying the major processes that control these rates, and developing conceptual models of the sensitivity of these processes to climate variability and change.

CO2-03: Iron Biogeochemistry
This project is evaluating the importance of iron and other trace micronutrient elements in driving Southern Ocean biogeochemical cycles. The research team will map the distribution of dissolved iron in waters south of Australia, fingerprint supply and removal mechanisms, and quantify trace element limitation of phytoplankton growth and community structure in (sub)-Antarctic ecosystems.

CO2-04: Effect of Elevated CO2 on Phytoplankton
This project is investigating how Southern Ocean phytoplankton and microbial communities will change as atmospheric carbon dioxide (CO2) concentrations increase. The research team is studying the likely changes in phytoplankton species and size distribution, in rates of uptake of CO2 through photosynthesis, and in the extent to which CO2 is recycled through the microbial loop or sedimented to the deep ocean.

CO2-05: Biogeochemical Simulations
Our research team is developing and applying mechanistic models to investigate the impact of global warming on the marine carbon cycle. We are determining how much atmospheric carbon dioxide is currently being taken up by the Southern Ocean and assessing how this may be affected by projected global climate change.