Electron Transpiration Cooling of Hypersonic Vehicles. Future aircraft for flight at hypersonic speeds require sharp leading edges for the best aerodynamic performance. Sharp leading edges incur high heat loads and cannot be adequately cooled with current technologies. The project aim is to investigate novel surface materials that emit electrons when heated. This emission of electrons from the surface can significantly contribute to the cooling of the sharp leading edges. This project is expecte ....Electron Transpiration Cooling of Hypersonic Vehicles. Future aircraft for flight at hypersonic speeds require sharp leading edges for the best aerodynamic performance. Sharp leading edges incur high heat loads and cannot be adequately cooled with current technologies. The project aim is to investigate novel surface materials that emit electrons when heated. This emission of electrons from the surface can significantly contribute to the cooling of the sharp leading edges. This project is expected to deliver new experimental data on novel surface materials exposed to a hypersonic flow environment and computer models that can simulate their cooling effect. This investigation will contribute towards enabling technologies for sustained hypersonic flight by overcoming critical head load limitations.Read moreRead less
Discovery Early Career Researcher Award - Grant ID: DE210100749
Funder
Australian Research Council
Funding Amount
$434,030.00
Summary
Machine learning of subgrid ocean physics for global ocean models. Climate projections require simulations with ocean-climate models for hundreds of years. Computational resources limit the resolution of our models for such long runs, meaning that some key physical processes remain unresolved and must be parameterised. This project uses machine learning to find new parameterisations for unresolved ocean processes. These new parameterisations will be implemented into computationally cheaper coars ....Machine learning of subgrid ocean physics for global ocean models. Climate projections require simulations with ocean-climate models for hundreds of years. Computational resources limit the resolution of our models for such long runs, meaning that some key physical processes remain unresolved and must be parameterised. This project uses machine learning to find new parameterisations for unresolved ocean processes. These new parameterisations will be implemented into computationally cheaper coarse-resolution ocean models, thereby enhancing these models' representation of the ocean circulation. This project expects to reveal the dynamics of unresolved processes, to improve the accuracy of climate projections and to provide a proof-of-concept for how machine learning can be used in ocean and climate science.Read moreRead less
Thermodynamics inversion for mineral systems. This project aims to provide a newly developed science approach to the Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP). AusLAMP provides unparalleled geophysical information aimed at unravelling the tectonic history of the Australian continent and its mineral potential. The project will use thermodynamically based geodynamic simulators to jointly analyse and quantify intraplate deformation. This will illuminate the cause of dri ....Thermodynamics inversion for mineral systems. This project aims to provide a newly developed science approach to the Australian Lithospheric Architecture Magnetotelluric Project (AusLAMP). AusLAMP provides unparalleled geophysical information aimed at unravelling the tectonic history of the Australian continent and its mineral potential. The project will use thermodynamically based geodynamic simulators to jointly analyse and quantify intraplate deformation. This will illuminate the cause of driving fluid flow thorough the lithosphere, mineralisation phenomena, their datasets and geometries, and dynamic aspects of the processes driving mineral systems.Read moreRead less
The convective boundaries in stars. This project aims to locate the boundaries of convection, a problem in models of stars. It will calculate high-resolution three-dimensional simulations of stars and observe star clusters. The effect of this advance on stellar modelling could be profound since almost all stars contain convective regions. Many branches of astronomy rely on stellar models so the effect could extend far beyond the immediate field, ultimately expanding understanding of the Universe ....The convective boundaries in stars. This project aims to locate the boundaries of convection, a problem in models of stars. It will calculate high-resolution three-dimensional simulations of stars and observe star clusters. The effect of this advance on stellar modelling could be profound since almost all stars contain convective regions. Many branches of astronomy rely on stellar models so the effect could extend far beyond the immediate field, ultimately expanding understanding of the Universe. It could also be crucial in realising the scientific advances of the surveys which are gathering data for up to a billion stars.Read moreRead less
Discovery Early Career Researcher Award - Grant ID: DE170100184
Funder
Australian Research Council
Funding Amount
$360,000.00
Summary
Understanding Antarctic dense water formation. This project aims to use a high-resolution global modelling approach to understand how Antarctic dense water formation changed in past climates and how to predict future changes. The Southern Ocean is critical in the uptake of heat and carbon from the atmosphere into the deep ocean. The sinking of cold and saline dense water around the coast of Antarctica transports heat and carbon into the deep ocean. Climate models fail to simulate this process an ....Understanding Antarctic dense water formation. This project aims to use a high-resolution global modelling approach to understand how Antarctic dense water formation changed in past climates and how to predict future changes. The Southern Ocean is critical in the uptake of heat and carbon from the atmosphere into the deep ocean. The sinking of cold and saline dense water around the coast of Antarctica transports heat and carbon into the deep ocean. Climate models fail to simulate this process and little is known about how dense water formation responds to changes in climate. Identification of critical vulnerabilities associated with Antarctic ice shelf melting and sea level rise will guide Southern Ocean observation systems and Australian climate adaptation programs.Read moreRead less
Snapper Science Program: Theme 1 - Biology And Ecology
Funder
Fisheries Research and Development Corporation
Funding Amount
$1,982,523.00
Summary
A comprehensive understanding of the general biology and ecology of any fishery species is fundamental to determine its response to exploitation and inform appropriate fishery management. Despite the significant body of research into the biology of Snapper, there remain considerable knowledge gaps regarding the underlying factors that drive interannual variation in juvenile recruitment and the demographic processes that maintain populations. Furthermore, there is uncertainty in how these process ....A comprehensive understanding of the general biology and ecology of any fishery species is fundamental to determine its response to exploitation and inform appropriate fishery management. Despite the significant body of research into the biology of Snapper, there remain considerable knowledge gaps regarding the underlying factors that drive interannual variation in juvenile recruitment and the demographic processes that maintain populations. Furthermore, there is uncertainty in how these processes will be influenced by changing environmental conditions associated with climate change. As such, understanding drivers of recruitment variability was identified as one of the highest research priorities for Snapper at the most recent National Workshop (FRDC Project No. 2019-085; Cartwright et al. 2021). Given the strong relationship between episodic recruitment and fishery production described above for the SG/WCS and GSVS, this recommendation was also strongly endorsed by fishery researchers, managers, and industry stakeholders in SA (Drew et al. 2022).
This research proposal has been developed to address four research priorities: • To understand the biological and environmental factors that affect recruitment of Snapper in SA and evaluate the potential influence of climate change. • Provide a contemporary understanding of stock structure for Snapper on the west coast of Eyre Peninsula to inform the appropriate spatial scale for fishery management. • Develop a contemporary series of biological parameters for each stock of Snapper in SA to be used as inputs in the stock assessment model. • Evaluate changes in the physical environment that may affect Snapper recruitment.
Consequently, Research Theme 1 – Biology and Ecology involves four projects: 1.1 Investigating recruitment variability and evaluating the potential effects of climate change for Snapper in South Australia 1.2 Contemporary demographic processes and stock structure for Snapper on the west coast of Eyre Peninsula 1.3 Review of biological parameters for Snapper in South Australia 1.4 Benthic habitat survey for Gulf St Vincent.
1.1 Investigating recruitment variability and evaluating the potential effects of climate change for Snapper in South Australia The population dynamics and fishery productivity for Snapper in SA are fundamentally driven by highly variable interannual recruitment, i.e., the number of age 0+ juveniles that enter the population each year (Fowler et al. 2017, Fowler and Jennings 2003). As such, a relative index of annual age 0+ juvenile abundance would be a powerful, fishery-independent tool to predict future trends in fishable biomass. To address this need, a recent project was undertaken to identify the most appropriate sampling methodology for age 0+ Snapper in SA’s gulfs and to develop a pre-recruit index (FRDC Project No. 2019-046). The first component of the present study involves the continuation of annual surveys for age 0+ Snapper for each stock to monitor trends in juvenile recruitment. The surveys will be repeated annually at the recognised nursery areas for each stock, i.e., northern Spencer Gulf (NSG) for the SG/WCS and northern Gulf St Vincent (NGSV) for the GSVS (Fowler et al. 2017). In addition, age 1+ juvenile Snapper will be sampled from annual fishery-independent surveys for the Spencer Gulf and Gulf St Vincent prawn fisheries, which will provide further information to determine relative year class strength.
The second component of the study involves investigating the relationships between environmental parameters and recruitment. The datasets for juvenile abundance will be considered with annual population age structures to develop a time series of recruitment for the two stocks (i.e., late 1960s to 2020s). Long-term time series of environmental parameters (e.g., temperature, salinity, productivity, wind stress) will be developed and compared to the time series of recruitment for each stock. In conjunction with the pre-recruit index, understanding the environmental influences that drive recruitment variability would provide even greater predictive capability to forecast trends in recruitment and fishable biomass, particularly under changing environmental conditions associated with climate change.
The third component of the study will investigate the potential effects of environmental change for Snapper in SA. Using the environmental datasets previously developed, a high-resolution oceanographic model for SA will be hindcast to determine the intensity of local environmental change and identify potential climate ‘hot spots’. The model will then be forecast with different climate change scenarios to predict changes in ocean conditions over the next 5, 10, and 50 years. Based on the physiological tolerance ranges for Snapper spawning and larval development, these predictions will be used to evaluate potential shifts in the availability of suitable environmental conditions for Snapper in SA. Such responses will be considered in terms of potential implications for future trends in recruitment and fishable biomass.
1.2 Contemporary demographic processes and stock structure for Snapper on the west coast of Eyre Peninsula There are three recognised stocks of Snapper in SA waters: the SG/WCS, the GSVS, and the Western Victoria Stock (WVS) (Fowler 2016, Fowler et al. 2017). The population of Snapper on the West Coast of Eyre Peninsula (WC) is a regional component of the SG/WCS. It is hypothesised that in most years, the WC population is replenished by local demographic processes that maintain the population at a relatively low level. However, episodically in years of exceptionally strong recruitment in northern Spencer Gulf (i.e., 1991, 1997, and 1999), the WC population is replenished through the density dependent emigration of fish of a few years of age that disperse from northern Spencer Gulf, through southern Spencer Gulf and to the WC. These fish then remain on the WC for the remainder of their lives.
As a consequence of the prolonged period of poor recruitment in northern Spencer Gulf since 1999 and the subsequent depletion of the population in Spencer Gulf, it is unlikely that this density dependent movement from Spencer Gulf to the WC has occurred to a major extent for a number of years or will occur until the Spencer Gulf population has recovered. Furthermore, age structures for the WC developed in 2020 and 2021 showed that only a very small number of fish from the strong 1997- and 1999-year classes in northern Spencer Gulf remained in the population, and there were several other year classes in the age structures for the WC that were not present in northern Spencer Gulf (Drew et al. 2022). Consequently, there is a need to understand the relative contributions of local population processes and emigration from northern Spencer Gulf to the WC population. This is particularly important following the regionalisation of the fishery through the Marine Scalefish Fishery (MSF) Reform (Smart et al. 2022).
This study will investigate the contemporary demographic processes that maintain the population of Snapper on the WC through the regional comparison of population age structures, elemental chemistry of otoliths, and population genomics. The findings will provide insight into the relative contributions of local recruitment and emigration to the WC population, that will be compared to the existing conceptual model of stock structure for Snapper in SA (Fowler 2016, Fowler et al. 2017). The proposed study will build on several previous projects that have investigated the stock structure of Snapper in SA (i.e., FRDC Project No. 2002-001, FRDC Project No. 2012-020, ARC Linkage Project No. LP180100756).
1.3 Review of biological parameters for Snapper in South Australia The biology of Snapper in SA has been studied over the past 40 years, with particular focus on northern Spencer Gulf (e.g., Jones 1981, 1987, McGlennon 2003). Since 2000, a weekly market sampling program has been undertaken by SARDI researchers that has provided biological data for Snapper caught by commercial fishers across SA. The sampling program has been augmented with periodic trips to regional areas, research cruises, and targeted research projects. Since the closure of the SG/WCS and GSVS in November 2019, biological samples from the two stocks have been accessed through a targeted sampling program which involved contracting commercial fishers. The data collected through these projects and programs is maintained in a MS Access database which currently contains biological information (i.e., capture date, location, length, weight, sex, reproductive stage, and age) for >27,000 Snapper and length information for >75,000 individuals.
This study will investigate potential changes in the biological characteristics of Snapper throughout SA over the past 40 years in response to temporal changes in environmental conditions and stock abundance. This will involve spatial and temporal comparisons of length, age, growth rate, and length at maturity for Snapper from each region of SA. The study will also consider various approaches to estimate natural mortality. A key output of the study is a summary of contemporary biological parameters for each stock of Snapper in SA that will be incorporated into the stock assessment model (‘SnapEst’).
1.4 Benthic habitat survey for Gulf St Vincent Snapper utilise a diversity of different benthic habitats throughout its life history, ranging from soft sediments that are favoured by recently settled juveniles to high relief structures that act as aggregation sites for spawning adults. As a result of the significant interannual variation in recruitment observed for Snapper in SA and the subsequent development of a pre-recruit index, there is particular interest in the spatial distribution and relative abundance of benthic habitats that act as nursery areas for age 0+ juvenile Snapper. In order for the pre-recruit index to provide reliable estimates of annual recruitment, it is essential that the key areas which support 0+ Snapper are sampled consistently each year.
In the recent project to develop a pre-recruit index (i.e., FRDC 2019-046), sampling for 0+ juvenile Snapper was targeted at the hypothesised nursery areas for each stock, i.e., northern Spencer Gulf (NSG) for the SG/WCS and northern Gulf St Vincent (NGSV) for the GSVS (Fowler et al. 2017). For NSG, the sampling design was informed by the results of annual surveys in the region from 2000 to 2010, which identified a strong relationship between the spatial distribution and abundance of 0+ Snapper and localised areas of soft, silty benthic substrate (Fowler and Jennings 2003, Fowler et al. 2010). There were no previous surveys for 0+ Snapper in NGSV, and therefore sampling locations were determined by the presence of suitable benthic substrate from existing habitat studies (Shepherd and Sprigg 1976, Tanner 2002). However, from 2021 to 2023, the catches of age 0+ Snapper in NGSV were very low in each annual survey and it cannot be determined if this reflected poor juvenile recruitment in these years, or if key nursery areas were not adequately sampled.
The aim of this study is to quantify the spatial distribution and relative abundance of benthic habitats in GSV, with particular emphasis on localised areas of soft substrate that may support age 0+ juvenile Snapper. The study will use towed underwater video and particle size analysis of sediment samples to quantify habitat types at ~150 sites throughout GSV following the methods recently applied in Spencer Gulf (FRDC 2020-002; Grammer et al. in prep.). The spatial distribution and relative abundance of benthic habitat types identified in this study will be compared to previous surveys in 1964-69 (Shepherd and Sprigg 1976) and 2000-01 (FRDC Project No. 1998-208; Tanner 2002) to assess changes in benthic habitats in GSV over the past 50 years, and how such changes may relate to trends in recruitment and stock abundance for Snapper over this time.
Objectives: 1. Quantify the abundance of age 0+ Snapper in northern Spencer Gulf and Gulf St Vincent to provide relative estimates of recruitment for 2024, 2025, and 2026. Examine the otoliths of these fish to improve the understanding of early life history processes. 2. Evaluate the relationships between environmental parameters and recruitment variability for Snapper in South Australia and evaluate the potential effects of environmental change on spawning and recruitment. 3. Determine the contemporary demographic processes that maintain Snapper populations on the west coast of Eyre Peninsula, i.e., local recruitment vs. emigration from adjacent regional populations, and to use this information to assess stock structure. 4. Assess possible changes in key biological parameters of Snapper for each stock in South Australia in response to temporal changes in environmental conditions and stock abundance. 5. Quantify the spatial distribution and relative abundance of benthic habitats utilised by juvenile Snapper in Gulf St Vincent and assess potential changes over the past 50 years. Read moreRead less
ARC Centre of Excellence for Climate Extremes. This Centre aims to transform understanding of past and present climate extremes and revolutionise Australia’s capability to predict them into the future. Climate extremes cost Australia up to $4 billion a year and will intensify over coming decades. This Centre’s blue-sky research will discover processes that explain the behaviour of present and future climate extremes. It will use its researchers, data, modelling, collaboration, graduate programme ....ARC Centre of Excellence for Climate Extremes. This Centre aims to transform understanding of past and present climate extremes and revolutionise Australia’s capability to predict them into the future. Climate extremes cost Australia up to $4 billion a year and will intensify over coming decades. This Centre’s blue-sky research will discover processes that explain the behaviour of present and future climate extremes. It will use its researchers, data, modelling, collaboration, graduate programme and early career researcher mentoring to transform Australia’s capacity to predict climate extremes. This research is expected to make Australia more resilient to climate extremes and minimise risks from climate extremes to the Australian environment, society and economy.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
Can Spatial Fishery-dependent Data Be Used To Determine Abalone Stock Status In A Spatially Structured Fishery?
Funder
Fisheries Research and Development Corporation
Funding Amount
$562,128.00
Summary
With the advent of the Status of Australian Fish Stocks (SAFS) process, there is now a requirement to provide a stock ‘status’ determination in addition to the annual TACC determination. The ‘status’ reflects changes in the overall biomass, the fishing mortality, or in their proxies. This has led to disagreements among researchers, managers and industry, largely due to uncertainty around how best to derive a meaningful overall stock status indicator to meet the requirements of the SAFS reporting ....With the advent of the Status of Australian Fish Stocks (SAFS) process, there is now a requirement to provide a stock ‘status’ determination in addition to the annual TACC determination. The ‘status’ reflects changes in the overall biomass, the fishing mortality, or in their proxies. This has led to disagreements among researchers, managers and industry, largely due to uncertainty around how best to derive a meaningful overall stock status indicator to meet the requirements of the SAFS reporting process. These higher-level reporting processes are an important demonstration of sustainable management of Australian fisheries, but only if stock status determinations are accurate and defensible.
Australian abalone fisheries primarily use harvest control rules based around CPUE (Kg/Hr) to set TACC. However, with abalone, stable catch-rates may not indicate stable biomass and/or stable density. Catch-rates are frequently criticised because the effort needed to take a quantity of catch may be influenced by density but also by density independent factors such as conditions at the time of fishing, experience, and the ability of fishers to adjust their fishing strategy to maintain catch rates (diver behaviour driven hyper-stability). While there are many issues with the assumption that CPUE is a reliable proxy for abundance, it is assumed to be so despite the absence of robust data to validate use of CPUE in this way. In some jurisdictions CPUE is supplemented by sparse fishery-dependent size and density data. There is an urgent need to review common assumptions, methods and interpretations of CPUE as a primary indicator, and to determine whether inclusion of spatial fishery data could provide a ‘global’ indicator of stock status for abalone fisheries.
Objectives: 1. Characterise the statistical properties, coherence, interpretability and assumptions of spatial and classic indicators of fishery performance 2. Develop methods for inclusion of fine-scale spatial data in CPUE standardisations 3. Identify methods for detecting hyper-stability in CPUE 4. Determine feasibility of spatial data based stock status determination in spatially structured fisheries Read moreRead less
Spanning ten billion scales from millimetre turbulence to global circulation. This project aims to explain the role of convection in the ocean. Convection is a key climate process yet it remains one of the most poorly understood mechanisms in the ocean and is crudely represented in climate models, leading to uncertainties in predictions of heat transport, climate change, polar ice loss and sea level rise. Using a unique turbulence-resolving approach and high-performance computing, the project wi ....Spanning ten billion scales from millimetre turbulence to global circulation. This project aims to explain the role of convection in the ocean. Convection is a key climate process yet it remains one of the most poorly understood mechanisms in the ocean and is crudely represented in climate models, leading to uncertainties in predictions of heat transport, climate change, polar ice loss and sea level rise. Using a unique turbulence-resolving approach and high-performance computing, the project will determine both the global role of buoyancy-driven convection in the broad ocean circulation and the local turbulence controls on melting rates of Antarctic ice-shelves. This will contribute to the formulation of better climate models and keep Australia at the forefront of oceanography and environmental fluid dynamics.Read moreRead less