Active Ice-Shelf Rift Systems on the Amery Ice Shelf, East Antarctica. Our work will inform the public on how the Antarctic might contribute to global sea level rise, e.g., are current iceberg production rates accelerating and causing inland ice to flow into the sea more rapidly? Furthermore, a greater understanding of the important Earth systems, including the ocean-ice-atmosphere system, is important to a society contemplating the responsibilities of stewardship of the planet as we move into t ....Active Ice-Shelf Rift Systems on the Amery Ice Shelf, East Antarctica. Our work will inform the public on how the Antarctic might contribute to global sea level rise, e.g., are current iceberg production rates accelerating and causing inland ice to flow into the sea more rapidly? Furthermore, a greater understanding of the important Earth systems, including the ocean-ice-atmosphere system, is important to a society contemplating the responsibilities of stewardship of the planet as we move into the era of potentially profound effects from global climate change.Read moreRead less
Looking back to see the future: Change in the Lambert Glacier and the East Antarctic Ice Sheet. To develop a comprehensive understanding of the Lambert Glacier of East Antarctica, from the time of the last maximum glaciation to the present, through an integrated and interdisciplinary study combining new field evidence - ice retreat history, geodetic measurements of crustal rebound, satellite measurements of present ice heights and changes therein - with other geological and glaciological data an ....Looking back to see the future: Change in the Lambert Glacier and the East Antarctic Ice Sheet. To develop a comprehensive understanding of the Lambert Glacier of East Antarctica, from the time of the last maximum glaciation to the present, through an integrated and interdisciplinary study combining new field evidence - ice retreat history, geodetic measurements of crustal rebound, satellite measurements of present ice heights and changes therein - with other geological and glaciological data and numerical geophysical modelling advances. The project contributes to the quantitative characterisation of the complex interactions between ice-sheets, oceans and solid earth within the climate system. Outcomes have implications for geophysics, glaciology, geomorphology, climate, and past and future sea-level change.Read moreRead less
Improving models of West Antarctic glacial isostatic adjustment through a new surface velocity field. This project seeks to "fix the scales" being used to weigh changes in the Antarctic ice sheet. Present measurements are biased by a failure to accurately account for mass changes beneath the ice and within the Earth itself. This project seeks to use new measurements of the changes in the shape of the Earth to calibrate out that bias.
Quantifying sea-level trends and extremes along Australia's coastal margin. Multi-decadal changes in sea-level, and sea-level extremes, cannot be well quantified along most global coastlines, including Australia's, because the high spatial variability of sea-level is under-sampled by the sparse set of long, high quality tide gauge records. Satellite altimetry provides an alternative data source with greater spatial sampling, yet experiences contamination from land within tens of kilometres from ....Quantifying sea-level trends and extremes along Australia's coastal margin. Multi-decadal changes in sea-level, and sea-level extremes, cannot be well quantified along most global coastlines, including Australia's, because the high spatial variability of sea-level is under-sampled by the sparse set of long, high quality tide gauge records. Satellite altimetry provides an alternative data source with greater spatial sampling, yet experiences contamination from land within tens of kilometres from the coast and also suffers from regionally correlated biases. This project proposes to address these problems through re-tracking radar altimetry waveforms to derive new data in the coastal margin, enabling the production of new inferences on sea-level change and extremes at dramatically improved spatial resolution around Australia.Read moreRead less
Improved Geodetic Modelling through Very Long Baseline Interferometry. We plan to develop a geodetic VLBI capability to provide independent confirmation of results from alternative techniques such as GPS and SLR and allow us to characterise and remove the systematic errors inherent in these systems, to produce an optimum, unified terrestrial reference system based on VLBI measurements, together with GPS/SLR data, especially for the Antarctic region. The ITRF is based on the VLBI ICRF linking ou ....Improved Geodetic Modelling through Very Long Baseline Interferometry. We plan to develop a geodetic VLBI capability to provide independent confirmation of results from alternative techniques such as GPS and SLR and allow us to characterise and remove the systematic errors inherent in these systems, to produce an optimum, unified terrestrial reference system based on VLBI measurements, together with GPS/SLR data, especially for the Antarctic region. The ITRF is based on the VLBI ICRF linking our astrometric and geodynamic research programs.
We will estimate motion at sites from the combination of VLBI, GPS, gravity and tide gauge data for geodynamic effects, such as post-glacial rebound and tectonic motion, global mean sea level change and determine length-of-day (LOD) variations, focused primarily on understanding the contribution from the Southern Oceans.
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Linkage Infrastructure, Equipment And Facilities - Grant ID: LE150100108
Funder
Australian Research Council
Funding Amount
$190,000.00
Summary
Earth’s response to ice unloading: a unique GPS measurement from Antarctica . Earth's response to ice unloading - a unique GPS measurement from Antarctica: This project aims to deploy geophysical equipment including global navigation satellite systems within Antarctica to understand how Earth responds to changes in stress (rheology) within the crust and upper mantle (the upper ~660 km). It exploits a globally-unique natural experiment that commenced in 2002 with the break-up of the Larsen B Ice ....Earth’s response to ice unloading: a unique GPS measurement from Antarctica . Earth's response to ice unloading - a unique GPS measurement from Antarctica: This project aims to deploy geophysical equipment including global navigation satellite systems within Antarctica to understand how Earth responds to changes in stress (rheology) within the crust and upper mantle (the upper ~660 km). It exploits a globally-unique natural experiment that commenced in 2002 with the break-up of the Larsen B Ice Shelf and which was followed by large-scale ice-mass unloading and rapid surface deformation. New broadband passive seismic and geodetic deformation measurements offer the promise of resolving a dichotomy between laboratory and millennial-scale determinations of Earth rheology through uniquely studying a time-scale mid-way between these extremes, whilst further strengthening Australia's emerging expertise in polar geophysics.Read moreRead less
Establishing the reference frame using astronomical and space-geodetic observations. Australia is increasingly dependent on spatial positioning and spatial data, yet mostly relies upon international agencies and research organisations to provide regular updates of coordinates and reference frame definition used on Earth. Improving the accuracy of the reference frame definition and our understanding of errors in the space-based measurements will provide new insights for studies of the Earth. The ....Establishing the reference frame using astronomical and space-geodetic observations. Australia is increasingly dependent on spatial positioning and spatial data, yet mostly relies upon international agencies and research organisations to provide regular updates of coordinates and reference frame definition used on Earth. Improving the accuracy of the reference frame definition and our understanding of errors in the space-based measurements will provide new insights for studies of the Earth. The research will yield results in studies of national significance, such as sea level rise, the effects of melting polar regions, and crustal deformation, as well as developing Australia's expertise in exploiting observations of the Earth from space.Read moreRead less
Earthquake biases in measurements of Antarctica's sea-level contribution. This project aims to accurately determine Antarctica’s contribution to present-day sea-level. Large technique-specific systematic errors make this uncertain and controversial with the sign of change not agreed. Three of four measurement techniques rely on knowing the solid earth's changing shape or gravity field. Studies have not considered post-seismic deformation, but GPS data show that Antarctica has deformed since the ....Earthquake biases in measurements of Antarctica's sea-level contribution. This project aims to accurately determine Antarctica’s contribution to present-day sea-level. Large technique-specific systematic errors make this uncertain and controversial with the sign of change not agreed. Three of four measurement techniques rely on knowing the solid earth's changing shape or gravity field. Studies have not considered post-seismic deformation, but GPS data show that Antarctica has deformed since the 1998 Magnitude-8.2 Antarctic Plate Earthquake. This project will develop a model of these earthquakes constrained by geodetic data and use the model to estimate Antarctica's contribution to sea-level change. This should enable more confident local, national and international planning. This will benefit society through reducing the sea-level projection uncertainty.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE150100105
Funder
Australian Research Council
Funding Amount
$570,000.00
Summary
Broadband receivers for AuScope geodetic and astronomical applications . Broadband receivers for AuScope geodetic and astronomical applications: This project aims to develop an innovative broadband receiver system which will be deployed on the AuScope array of radio telescopes. This will enable the telescopes to play a key role in improving precision navigation both in Australia and throughout the Southern Hemisphere. The new receiver systems will significantly improve the capability of these fa ....Broadband receivers for AuScope geodetic and astronomical applications . Broadband receivers for AuScope geodetic and astronomical applications: This project aims to develop an innovative broadband receiver system which will be deployed on the AuScope array of radio telescopes. This will enable the telescopes to play a key role in improving precision navigation both in Australia and throughout the Southern Hemisphere. The new receiver systems will significantly improve the capability of these facilities for both geodetic and astronomical investigations. Improvements to the accuracy of the terrestrial reference frame in Australia will allow more accurate measurements of changes in sea level, while high precision astrometric observations undertaken with the new receivers will be used to determine the structure of our Milky Way Galaxy.Read moreRead less
Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0236393
Funder
Australian Research Council
Funding Amount
$175,000.00
Summary
A Gigabit per second Data Recording System for Geodesy and Astronomy. We plan to acquire a gigabit per second digital data recorder for geodesy and astronomy. We will develop a geodetic VLBI capability to provide independent confirmation of results from alternative techniques such as GPS and SLR and allow us to characterise and remove the systematic errors inherent in these systems. We will estimate motion at sites from the combination of VLBI, GPS, gravity and tide gauge data for geodynamic ef ....A Gigabit per second Data Recording System for Geodesy and Astronomy. We plan to acquire a gigabit per second digital data recorder for geodesy and astronomy. We will develop a geodetic VLBI capability to provide independent confirmation of results from alternative techniques such as GPS and SLR and allow us to characterise and remove the systematic errors inherent in these systems. We will estimate motion at sites from the combination of VLBI, GPS, gravity and tide gauge data for geodynamic effects, such as post-glacial rebound and tectonic motion and global mean sea level change.
We will increase the density of southern radio sources used to define the International Celestial Reference Frame and investigate their structure and evolution. We will make high time resolution observations of young pulsars to study the phenomena of pulsar glitches and aid in the understanding of neutron star interiors.Read moreRead less