<div>The Abbot Point to Hydrographers Passage bathymetry survey was acquired for the Australian Hydrographic Office (AHO) onboard the RV Escape during the period 6 Oct 2020 – 16 Mar 2021. This was a contracted survey conducted for the Australian Hydrographic Office by iXblue Pty Ltd as part of the Hydroscheme Industry Partnership Program. The survey area encompases a section of Two-Way Route from Abbot Point through Hydrographers Passage QLD. Bathymetry data was acquired using a Kongsberg EM 2040, and processed using QPS QINSy. The dataset was then exported as a 30m resolution, 32 bit floating point GeoTIFF grid of the survey area.</div><div>This dataset is not to be used for navigational purposes.</div>

<div>The A1 poster incorporates 4 images of Australia taken from space by Earth observing satellites. The accompanying text briefly introduces sensors and the bands within the electromagnetic spectrum. The images include examples of both true and false colour and the diverse range of applications of satellite images such as tracking visible changes to the Earth’s surface like crop growth, bushfires, coastal changes and floods. Scientists, land and emergency managers use satellite images to analyse vegetation, surface water or human activities as well as evaluate natural&nbsp;hazards.</div>

The Historical Bushfire Boundaries service represents the aggregation of jurisdictional supplied burnt areas polygons stemming from the early 1900's through to 2022 (excluding the Northern Territory). The burnt area data represents curated jurisdictional owned polygons of both bushfires and prescribed (planned) burns. To ensure the dataset adhered to the nationally approved and agreed data dictionary for fire history Geoscience Australia had to modify some of the attributes presented. The information provided within this service is reflective only of data supplied by participating authoritative agencies and may or may not represent all fire history within a state.

To understand earth processes, geoscientists infer subsurface earth properties such as electromagnetic resistivity or seismic velocity from surface observations of electromagnetic or seismic data. These properties are used to populate an earth model vector, and the spatial variation of properties across this vector sheds light on the underlying earth structure or physical phenomenon of interest, from groundwater aquifers to plate tectonics. However, to infer these properties the spatial characteristics of these properties need to be known in advance. Typically, assumptions are made about the length scales of earth properties, which are encoded a priori in a Bayesian probabilistic setting. In an optimisation setting, appeals are made to promote model simplicity together with constraints which keep models close to a preferred model. All of these approaches are valid, though they can lead to unintended features in the resulting inferred geophysical models owing to inappropriate prior assumptions, constraints or even the nature of the solution basis functions. In this work it will be shown that in order to make accurate inferences about earth properties, inferences can first be made about the underlying length scales of these properties in a very general solution basis. From a mathematical point of view, these spatial characteristics of earth properties can be conveniently thought of as “properties” of the earth properties. Thus, the same machinery used to infer earth properties can be used to infer their length scales. This can be thought of as an “infer to infer” paradigm analogous to the “learning to learn” paradigm which is now commonplace in the machine learning literature. However, it must be noted that (geophysical) inference is not the same as (machine) learning, though there are many common elements which allow for cross-pollination of useful ideas from one field to the other, as is shown here. A non-stationary trans-dimensional Gaussian Process (TDGP) is used to parameterise earth properties, and a multi-channel stationary TDGP is used to parameterise the length scales associated with the earth property in question. Using non-stationary kernels, i.e., kernels with spatially variable length scales, models with sharp discontinuities can be represented within this framework. As GPs are multi-dimensional interpolators, the same theory and computer code can be used to solve geophysical problems in 1D, 2D and 3D. This is demonstrated through a combination of 1D and 2D non-linear regression examples and a controlled source electromagnetic (CSEM) field example. The key difference between this and previous work using TDGP is generalised nested inference and the marginalisation of prior length scales for better posterior subsurface property characterisation. <b>Citation:</b> Anandaroop Ray, Bayesian inversion using nested trans-dimensional Gaussian processes, <i>Geophysical Journal International</i>, Volume 226, Issue 1, July 2021, Pages 302–326, <a href="https://doi.org/10.1093/gji/ggab114">https://doi.org/10.1093/gji/ggab114</a>

This map is part of the AUSTopo - Australian Digital Topographic Map Series. It covers the whole of Australia at a scale of 1:250 000 (1cm on a map represents 2.5 km on the ground) and comprises 516 maps. This is the largest scale at which published topographic maps cover the entire continent. Each standard map covers an area of approximately 1.5 degrees longitude by 1 degree latitude or about 150 kilometres from east to west and at least 110 kilometres from north to south. The topographic map shows approximate coverage of the sheets. The map may contain information from surrounding map sheets to maximise utilisation of available space on the map sheet. There are about 50 special maps in the series and these maps cover a non-standard area. Typically, where a map produced on standard sheet lines is largely ocean it is combined with its landward neighbour. These maps contain natural and constructed features including road and rail infrastructure, vegetation, hydrography, contours (interval 50m), localities and some administrative boundaries. Coordinates: Geographical and MGA Datum: GDA94, GDA2020, AHD. Projection: Universal Traverse Mercator (UTM) Medium: Digital PDF download.

This map is part of the AUSTopo - Australian Digital Topographic Map Series. It covers the whole of Australia at a scale of 1:250 000 (1cm on a map represents 2.5 km on the ground) and comprises 516 maps. This is the largest scale at which published topographic maps cover the entire continent. Each standard map covers an area of approximately 1.5 degrees longitude by 1 degree latitude or about 150 kilometres from east to west and at least 110 kilometres from north to south. The topographic map shows approximate coverage of the sheets. The map may contain information from surrounding map sheets to maximise utilisation of available space on the map sheet. There are about 50 special maps in the series and these maps cover a non-standard area. Typically, where a map produced on standard sheet lines is largely ocean it is combined with its landward neighbour. These maps contain natural and constructed features including road and rail infrastructure, vegetation, hydrography, contours (interval 50m), localities and some administrative boundaries. Coordinates: Geographical and MGA Datum: GDA94, GDA2020, AHD. Projection: Universal Traverse Mercator (UTM) Medium: Digital PDF download.

This map is part of the AUSTopo - Australian Digital Topographic Map Series. It covers the whole of Australia at a scale of 1:250 000 (1cm on a map represents 2.5 km on the ground) and comprises 516 maps. This is the largest scale at which published topographic maps cover the entire continent. Each standard map covers an area of approximately 1.5 degrees longitude by 1 degree latitude or about 150 kilometres from east to west and at least 110 kilometres from north to south. The topographic map shows approximate coverage of the sheets. The map may contain information from surrounding map sheets to maximise utilisation of available space on the map sheet. There are about 50 special maps in the series and these maps cover a non-standard area. Typically, where a map produced on standard sheet lines is largely ocean it is combined with its landward neighbour. These maps contain natural and constructed features including road and rail infrastructure, vegetation, hydrography, contours (interval 50m), localities and some administrative boundaries. Coordinates: Geographical and MGA Datum: GDA94, GDA2020, AHD. Projection: Universal Traverse Mercator (UTM) Medium: Digital PDF download.

This map is part of the AUSTopo - Australian Digital Topographic Map Series. It covers the whole of Australia at a scale of 1:250 000 (1cm on a map represents 2.5 km on the ground) and comprises 516 maps. This is the largest scale at which published topographic maps cover the entire continent. Each standard map covers an area of approximately 1.5 degrees longitude by 1 degree latitude or about 150 kilometres from east to west and at least 110 kilometres from north to south. The topographic map shows approximate coverage of the sheets. The map may contain information from surrounding map sheets to maximise utilisation of available space on the map sheet. There are about 50 special maps in the series and these maps cover a non-standard area. Typically, where a map produced on standard sheet lines is largely ocean it is combined with its landward neighbour. These maps contain natural and constructed features including road and rail infrastructure, vegetation, hydrography, contours (interval 50m), localities and some administrative boundaries. Coordinates: Geographical and MGA Datum: GDA94, GDA2020, AHD. Projection: Universal Traverse Mercator (UTM) Medium: Digital PDF download.

This map is part of the AUSTopo - Australian Digital Topographic Map Series. It covers the whole of Australia at a scale of 1:250 000 (1cm on a map represents 2.5 km on the ground) and comprises 516 maps. This is the largest scale at which published topographic maps cover the entire continent. Each standard map covers an area of approximately 1.5 degrees longitude by 1 degree latitude or about 150 kilometres from east to west and at least 110 kilometres from north to south. The topographic map shows approximate coverage of the sheets. The map may contain information from surrounding map sheets to maximise utilisation of available space on the map sheet. There are about 50 special maps in the series and these maps cover a non-standard area. Typically, where a map produced on standard sheet lines is largely ocean it is combined with its landward neighbour. These maps contain natural and constructed features including road and rail infrastructure, vegetation, hydrography, contours (interval 50m), localities and some administrative boundaries. Coordinates: Geographical and MGA Datum: GDA94, GDA2020, AHD. Projection: Universal Traverse Mercator (UTM) Medium: Digital PDF download.