Pyrite: a deep-time capsule of ocean chemistry and atmosphere oxidation. Surprisingly little is known about trace element trends in past oceans, even though these data are vital for interpreting the evolution of the Earth's atmosphere, evolutionary pathways of marine life and cycles of major mineral deposits. Using laser-based analysis of sedimentary pyrite in deep marine rocks, this project aims to produce, for the first time, temporal variation curves for 25 trace elements in seawater over the ....Pyrite: a deep-time capsule of ocean chemistry and atmosphere oxidation. Surprisingly little is known about trace element trends in past oceans, even though these data are vital for interpreting the evolution of the Earth's atmosphere, evolutionary pathways of marine life and cycles of major mineral deposits. Using laser-based analysis of sedimentary pyrite in deep marine rocks, this project aims to produce, for the first time, temporal variation curves for 25 trace elements in seawater over the last 3.5 billion years. Preliminary research has validated the technique and demonstrated major changes in certain trace elements over geologically short periods. Outcomes will assist the minerals industry in the discovery of new deposits of zinc, copper, gold and iron ore in Australia.Read moreRead less
Calcification and shell chemistry response of Southern Ocean planktic foraminifers to ocean acidification and changing climates. Plankton that form tiny calcium carbonate shells will be cultured to determine how they will respond to acidification of the Southern Ocean caused by rising CO2 in the atmosphere. The same experiments will be used to gauge from their fossil shells how the Southern Ocean has caused and responded to changing atmosphere CO2 over the last glacial climate cycle
Impact of Metal - Reactive Oxygen Species (ROS) Interactions on Growth and Toxicity of Ichthyotoxic Algae in Australian Coastal Waters. Toxic algal blooms in estuarine and coastal waters can have devastating economic and ecological impacts but remarkably little is known about the factors that control either organism growth or toxin severity. Recent studies suggest that the interplay between delivery of the nutrient trace metals iron and copper and the method via which the organism acts to assimi ....Impact of Metal - Reactive Oxygen Species (ROS) Interactions on Growth and Toxicity of Ichthyotoxic Algae in Australian Coastal Waters. Toxic algal blooms in estuarine and coastal waters can have devastating economic and ecological impacts but remarkably little is known about the factors that control either organism growth or toxin severity. Recent studies suggest that the interplay between delivery of the nutrient trace metals iron and copper and the method via which the organism acts to assimilate these metals is critical to the generation and aggressiveness of the toxins produced. These processes will be investigated in this study and conceptual and mathematical models will be developed which will assist in assessing management options for estuarine and coastal environments.Read moreRead less
Natural iron fertilisation of oceans around Australia: linking terrestrial dust, marine biogeochemistry and climate. Oceans play a vital role in Earth’s climate through the control of atmospheric carbon dioxide. An important component of this system is the iron cycle, in which iron-rich dust is transported from the land via atmosphere to ocean; iron is a key micronutrient for marine phytoplankton, the scarcity of which limits essential biogeochemical processes and ocean fertility. This project w ....Natural iron fertilisation of oceans around Australia: linking terrestrial dust, marine biogeochemistry and climate. Oceans play a vital role in Earth’s climate through the control of atmospheric carbon dioxide. An important component of this system is the iron cycle, in which iron-rich dust is transported from the land via atmosphere to ocean; iron is a key micronutrient for marine phytoplankton, the scarcity of which limits essential biogeochemical processes and ocean fertility. This project will conduct an integrated oceanographic and atmospheric observational program for trace elements in the oceans around Australia. This will provide the critical information on iron supplied from atmospheric dust for ocean productivity and marine ecosystem health, providing the science for predicting a key factor in the future impact of the oceans on climate.Read moreRead less
Dust to the ocean: Does it really increase productivity? This project aims to investigate the relationship between dust deposition and marine productivity. This project will quantify dust deposition to the ocean and its chemical and ecological impact by using new geochemical techniques and novel approaches with autonomous ocean sensors. Expected outcomes of this project include improved estimates of dust deposition to the ocean and the development of globally-applicable methods for quantifying t ....Dust to the ocean: Does it really increase productivity? This project aims to investigate the relationship between dust deposition and marine productivity. This project will quantify dust deposition to the ocean and its chemical and ecological impact by using new geochemical techniques and novel approaches with autonomous ocean sensors. Expected outcomes of this project include improved estimates of dust deposition to the ocean and the development of globally-applicable methods for quantifying the link between dust and biology using profiling floats. This should provide significant benefits such as improved dust models used to predict future changes in nutrient deposition, with implications for predicting future ocean fish production and carbon uptake.Read moreRead less
Deciphering strategies polar phytoplankton employ to lessen iron limitation. The Southern Ocean is of global importance. It comprises one-third of the global ocean by area and disproportionately absorbs two-thirds of anthropogenic ocean heat and half of anthropogenic carbon dioxide (CO2) emissions even though phytoplankton in this region are chronically iron-limited. This project aims to understand why copper uptake by phytoplankton lessens the effects of iron limitation and how copper substitut ....Deciphering strategies polar phytoplankton employ to lessen iron limitation. The Southern Ocean is of global importance. It comprises one-third of the global ocean by area and disproportionately absorbs two-thirds of anthropogenic ocean heat and half of anthropogenic carbon dioxide (CO2) emissions even though phytoplankton in this region are chronically iron-limited. This project aims to understand why copper uptake by phytoplankton lessens the effects of iron limitation and how copper substitutes for iron. This knowledge is critical for evaluating the impacts and feedbacks between iron and copper in regulating Southern Ocean productivity and ultimately its ability to drawdown atmospheric CO2. The results from this project will facilitate the development of improved ecosystem models and conservation tools.Read moreRead less
The Southern Ocean's response to abrupt climate change. This project aims to determine how the Southern Ocean responds to abrupt climate change, through geochemical analysis of marine sediment cores. Rapid warming events of the last ice age provide an analogue to human-caused warming. Experiments using ocean climate models will evaluate the drivers and consequences of the biogeochemical response of different sectors and zones of the Southern Ocean. The intended outcome is a better understanding ....The Southern Ocean's response to abrupt climate change. This project aims to determine how the Southern Ocean responds to abrupt climate change, through geochemical analysis of marine sediment cores. Rapid warming events of the last ice age provide an analogue to human-caused warming. Experiments using ocean climate models will evaluate the drivers and consequences of the biogeochemical response of different sectors and zones of the Southern Ocean. The intended outcome is a better understanding of how and why climate change impacts ocean productivity in the ecologically significant Southern Ocean. This will lead to better representations of carbon feedbacks in climate models and more robust projections of future climate change.Read moreRead less
Changes in the ocean's biological pump: innovative models and diagnostics. This Project aims to quantify how the ocean’s biological pump, which exports newly formed organic matter into the ocean interior, responds to environmental change. The biological pump is a key control on the global carbon and oxygen cycles, and hence on the viability of marine life. New, efficient numerical models will be developed and analysed with highly innovative mathematical methods. Expected outcomes are optimised .... Changes in the ocean's biological pump: innovative models and diagnostics. This Project aims to quantify how the ocean’s biological pump, which exports newly formed organic matter into the ocean interior, responds to environmental change. The biological pump is a key control on the global carbon and oxygen cycles, and hence on the viability of marine life. New, efficient numerical models will be developed and analysed with highly innovative mathematical methods. Expected outcomes are optimised predictive models and a new understanding of the possible future evolutions of the ocean carbon cycle, acidification, and oxygenation. This should provide significant benefits such as predictions of future ocean health, identification of processes that are sensitive to change, and strategies for marine resource management.Read moreRead less
Using the last glacial cycle to understand carbon-climate feedbacks . This project aims to investigate how the ocean’s carbon cycle will respond to anthropogenic climate change by examining its response to past climate variability. The project expects to generate new records of the dust feedback cycle and the microbial decomposition feedback cycle in the poorly studied Indian sector of the Southern Ocean. Expected outcomes include new datasets to test climate models, and a new method to detect t ....Using the last glacial cycle to understand carbon-climate feedbacks . This project aims to investigate how the ocean’s carbon cycle will respond to anthropogenic climate change by examining its response to past climate variability. The project expects to generate new records of the dust feedback cycle and the microbial decomposition feedback cycle in the poorly studied Indian sector of the Southern Ocean. Expected outcomes include new datasets to test climate models, and a new method to detect temperature-driven changes in microbial decomposition. This should lead to significant benefits including more accurate estimates of how much carbon humanity can safely emit, and the science to inform whether Australia should adopt ocean fertilisation as a strategy to combat climate change. Read moreRead less
Hot iron: Are submarine volcanoes important for Southern Ocean iron supply? The scarcity of iron limits biological productivity and carbon uptake in the nutrient rich waters of the Southern Ocean. This project will explore for the first time the role of undersea "hot spot" volcanoes in supplying iron to surface waters, thus linking the solid earth and the biosphere. The project will measure iron abundance, reactivity and nutritional value in buoyant plumes emanating from vents near Heard/McDonal ....Hot iron: Are submarine volcanoes important for Southern Ocean iron supply? The scarcity of iron limits biological productivity and carbon uptake in the nutrient rich waters of the Southern Ocean. This project will explore for the first time the role of undersea "hot spot" volcanoes in supplying iron to surface waters, thus linking the solid earth and the biosphere. The project will measure iron abundance, reactivity and nutritional value in buoyant plumes emanating from vents near Heard/McDonald Islands, Australia's only active volcanoes. The project aims to estimate the hydrothermal contribution to regional biological productivity and extrapolate to the whole Southern Ocean. Successful outcomes will benefit Australia by identifying iron sources that govern productivity and carbon uptake of an economically important ecosystem.Read moreRead less