The Southern Ocean Meridional Overturning Circulation: New observations of vertical mixing. The Southern Ocean and Antarctic Circumpolar Current (ACC) play profound roles in Australian and global climate. However, we know little about how they will be affected by global warming. New velocity observations will tell us how the vertical mixing that contributes to the meridional overturning circulation, and ACC strength, change with the seasons and from year to year. The observations will also gi ....The Southern Ocean Meridional Overturning Circulation: New observations of vertical mixing. The Southern Ocean and Antarctic Circumpolar Current (ACC) play profound roles in Australian and global climate. However, we know little about how they will be affected by global warming. New velocity observations will tell us how the vertical mixing that contributes to the meridional overturning circulation, and ACC strength, change with the seasons and from year to year. The observations will also give us a better understanding of the oceanic and atmospheric processes that drive these changes. This new information will allow climate models to be better constrained so they can more accurately predict changes to Australian and global climate.Read moreRead less
Antarctica's leaky defence to poleward heat transport. Southern Ocean currents are barriers to the oceanic transport of heat toward Antarctica. This barrier breaks down at key locations along their path and the poleward heat transport is enhanced. Changing winds are expected to accelerate heat transport, threatening ice shelves that protect Antarctic glaciers from ocean-driven melt. This project aims to advance understanding of the small-scale processes that control heat transport across the Sou ....Antarctica's leaky defence to poleward heat transport. Southern Ocean currents are barriers to the oceanic transport of heat toward Antarctica. This barrier breaks down at key locations along their path and the poleward heat transport is enhanced. Changing winds are expected to accelerate heat transport, threatening ice shelves that protect Antarctic glaciers from ocean-driven melt. This project aims to advance understanding of the small-scale processes that control heat transport across the Southern Ocean. By combining funded international field campaigns that harness new advances in observing systems with next-generation numerical modelling, this research will create a step-change in our ability to predict Southern Ocean environmental change.Read moreRead less
How topography brakes the Antarctic Circumpolar Current. This project aims to observe and simulate the mechanisms that slow the Antarctic Circumpolar Current. The Southern Ocean winds have increased over the last two decades while the transport of the world’s largest current remains steady or slightly decreasing. A possible explanation is negative feedback mechanisms between the winds and transport of the Antarctic Circumpolar Current. This project will observe how eddies carry momentum from the ....How topography brakes the Antarctic Circumpolar Current. This project aims to observe and simulate the mechanisms that slow the Antarctic Circumpolar Current. The Southern Ocean winds have increased over the last two decades while the transport of the world’s largest current remains steady or slightly decreasing. A possible explanation is negative feedback mechanisms between the winds and transport of the Antarctic Circumpolar Current. This project will observe how eddies carry momentum from the wind down to the sea floor and accelerate the deep currents that drag against the rough bottom to put the brakes on this current. Since this current affects Australian rainfall patterns and agricultural output, findings could inform public policy.Read moreRead less
Southern Ocean Sea Ice – what happened and what happens next? This project will adress our lack of confidence in future projections of sea ice around Antarctica by elucidating the mechanisms controlling sea ice in the Southern Ocean.
There is low confidence is current sea ice projections, limiting our ability to predict ice shelf melt and sea level rise.
This project will lead to a detailed understanding of the future of sea ice in the Southern Ocean, improving our understanding of ocean dynam ....Southern Ocean Sea Ice – what happened and what happens next? This project will adress our lack of confidence in future projections of sea ice around Antarctica by elucidating the mechanisms controlling sea ice in the Southern Ocean.
There is low confidence is current sea ice projections, limiting our ability to predict ice shelf melt and sea level rise.
This project will lead to a detailed understanding of the future of sea ice in the Southern Ocean, improving our understanding of ocean dynamics, ice shelf melt, and sea level rise.
The results from this project will enhance projections of sea ice, and therefore also ice shelf melt and sea level rise. Improved sea level projections will aid policy decisions for coastal communities.Read moreRead less
Understanding spread in sea level rise projections. This project aims to investigate changes in water properties and ocean circulation mechanisms leading to intermodel spread in sea-level projections. Sea-level rise projections for this 21st century largely disagree in magnitude and spatial changes between climate models, particularly in hotspots. The expected outcomes will contribute towards more rigorous constraints on the likelihood of future warming and sea-level rise projections, and are al ....Understanding spread in sea level rise projections. This project aims to investigate changes in water properties and ocean circulation mechanisms leading to intermodel spread in sea-level projections. Sea-level rise projections for this 21st century largely disagree in magnitude and spatial changes between climate models, particularly in hotspots. The expected outcomes will contribute towards more rigorous constraints on the likelihood of future warming and sea-level rise projections, and are aligned with scientific deliverables required to address key questions in support of Australia’s climate change policy. They are also aligned with international scientific deliverables in support of the World Climate Research Programme Grand Challenge on Regional Sea Level Change and Coastal Impacts.Read moreRead less
Australia's variable rainfall - how dry or wet can it really get? Australia’s rainfall is extremely variable, which means existing weather records are too short to calculate the true risk posed by droughts and floods. This project aims to quantify how naturally variable the rainfall coming from the Indo-Pacific mid-latitudes is, allowing recent rainfall extremes and future projections to be assessed in a long-term context. This project expects to produce new estimates of atmospheric moisture bud ....Australia's variable rainfall - how dry or wet can it really get? Australia’s rainfall is extremely variable, which means existing weather records are too short to calculate the true risk posed by droughts and floods. This project aims to quantify how naturally variable the rainfall coming from the Indo-Pacific mid-latitudes is, allowing recent rainfall extremes and future projections to be assessed in a long-term context. This project expects to produce new estimates of atmospheric moisture budgets between Australia and Antarctica based on a novel, 1000-year length reconstruction of moisture-bearing southern Indian Ocean storms. This new information is critically needed by water managers so that they can properly calculate (and ultimately prepare for) the worst of Australia’s rainfall-related risks.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
Equator to Pole: Reconstructing tropical and Antarctic climate variability over the last millennium and their impacts on southern Australian rainfall. Water resource management is one of the greatest challenges facing sustainable agriculture and urban populations across southern Australia. Key players driving catastrophic droughts in southern Australia are the tropical Indian Ocean Dipole and polar Southern Annual Mode climate systems, which affect moisture availability and transport pathways. T ....Equator to Pole: Reconstructing tropical and Antarctic climate variability over the last millennium and their impacts on southern Australian rainfall. Water resource management is one of the greatest challenges facing sustainable agriculture and urban populations across southern Australia. Key players driving catastrophic droughts in southern Australia are the tropical Indian Ocean Dipole and polar Southern Annual Mode climate systems, which affect moisture availability and transport pathways. This collaborative research project draws together a uniquely-skilled research team to develop targeted coral, ice and cave reconstructions of these climate systems and their impacts on Australian rainfall through the last millennium. This fundamental new knowledge of the drivers of Australian rainfall variability will aid improved predictability of future changes in our valuable water resources. Read moreRead less
Southern Ocean aerosols: sources, sinks and impact on cloud properties. This project aims to provide fundamental process-level understanding of atmospheric aerosol processes over the Southern Ocean, a region that has a profound influence on the Australian and global climate and where climate models perform poorly. Comprehensive observations during 3 Southern Ocean voyages and land-based measurements will enhance our knowledge of aerosols and cloud formation in that region and provide much-needed ....Southern Ocean aerosols: sources, sinks and impact on cloud properties. This project aims to provide fundamental process-level understanding of atmospheric aerosol processes over the Southern Ocean, a region that has a profound influence on the Australian and global climate and where climate models perform poorly. Comprehensive observations during 3 Southern Ocean voyages and land-based measurements will enhance our knowledge of aerosols and cloud formation in that region and provide much-needed data for improving global climate models. Expected outcomes include more accurate seasonal and latitudinal representations of Southern Ocean aerosol populations, properties and sources. The main benefit includes improvements in weather forecasting and future climate projection for Australia and the Southern Hemisphere.Read moreRead less
Winter Foraging Locations Of Southern Ocean Predators In Relation To Stochastic Variation In Sea-Ice Extent. Antarctic marine communities are likely to be amongst the first anywhere to show changes due to climate change. A top national priority for Australia is to understand how Antarctic communities will be affected if climate change does occur. As predators reflect changes occurring lower in the food chain, these are an important group to study. This study will be the first to specifically lin ....Winter Foraging Locations Of Southern Ocean Predators In Relation To Stochastic Variation In Sea-Ice Extent. Antarctic marine communities are likely to be amongst the first anywhere to show changes due to climate change. A top national priority for Australia is to understand how Antarctic communities will be affected if climate change does occur. As predators reflect changes occurring lower in the food chain, these are an important group to study. This study will be the first to specifically link ice extent with the habitat use of predators, and quantify how this varies over time. Some work already indicates that there have been community level changes in some predators in the Antarctic due to changes in ice extent, so developing tools to predict the nature and magnitude of these changes are needed. Read moreRead less