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  • This paper presents a new style of bedload parting from western Torres Strait, northern Australia. Outputs from a hydrodynamic model identified an axis of bedload parting centred on the western Torres Strait islands (~142°15"E). Unlike bedload partings described elsewhere in the literature, those in Torres Strait are generated by incoherence between two adjacent tidal regimes as opposed to overtides. Bedload parting is further complicated by the influence of wind-driven currents. During the trade wind season, wind-driven currents counter the reversing tidal currents to a point where peak currents are directed west. The eastwards-directed bedload pathway is only active during the monsoon season. Satellite imagery was used to describe six bedform facies associated with the bedload parting. Bedform morphology was used to indicate sediment supply. Contrary to bedload partings elsewhere, sand ribbons are a distal facies within the western bedload transport pathway despite peak currents directed toward the west throughout the year. This indicates that sediment is preferentially trapped within sand banks near the axis of parting and not transported further west into the Gulf of Carpentaria or Arafura Sea.

  • We measured the light absorption properties of two naturally occurring Australian hydrocarbon oils, a Gippsland light crude oil and a North West Shelf light condensate. Using these results in conjunction with estimated sensor environmental noise thresholds, the theoretical minimum limit of detectability of each oil type (as a function of oil thickness) was calculated for both the hyperspectral HYMAP and multispectral Quickbird sensors. The Gippsland crude oil is discernable at layer thickness of 20 micro metres or more in the Quickbird green channel. The HYMAP sensor was found to be theoretically capable of detecting a layer of Gippsland crude oil with a thickness of 10 micro metres in approximately six sensor channels. By contrast, the North West Shelf light condensate was not able to be detected by either sensor for any thickness up to 200 icro metres. Optical remote sensing is therefore not applicable for detecting diagnostic absorption features associated with this light condensate oil type, which is considered representative for the prospective Australian Northwest Shelf area. We conclude that oil type is critical to the applicability of optical remote sensing for natural oil slick detection and identification. We recommend that a sensor- and oil-specific sensitivity study should be conducted prior to applying optical remote sensors for oil exploration. The oil optical properties were obtained using two different laboratory methods, a reflectance-based approach and transmittance-based approach. The reflectance-based approach was relatively complex to implement, but was chosen in order to replicate as closely as possible real world remote sensing measurement conditions of an oil film on water. The transmittance-based approach, based upon standard laboratory spectrophotometric measurements was found to generate results in good agreement with the reflectance-based approach. Therefore, for future oil- and sensor-specific sensitivity studies, we recommend the relatively accessible transmittance-based approach, which is detailed in this paper.

  • Improving techniques for mapping land surface composition at regional- to continental-scale is the next step in delivering the benefits of remote sensing technology to Australia. New methodologies and collaborative efforts have been made as part of a multi-agency project to facilitate uptake of these techniques. Calibration of ASTER data with HyMAP has been very promising, and following an program in Queensland, a mosaic has been made for the Gawler-Curnamona region in South Australia. These programs, undertaken by Geoscience Australia, CSIRO, and state and industry partners, aims to refine and standardise processing and to make them easily integrated with other datasets in a GIS.

  • Geoscience Australia, ACRES distribute Landsat Multispectral Scanner (MSS), Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) data for a series of epochs or time frames covering Australia. The first epoch is 1972. These data have been produced and provided by the Australian Greenhouse Office (AGO). AGO use the data in their National Carbon Accounting System for monitoring land clearing and revegetation. This data is only available through ACRES and ACRES Landsat Distributors, and not through the AGO. More information is available at <a href="http://www.ga.gov.au/acres/prod_ser/agosuite.jsp">http://www.ga.gov.au/acres/prod_ser/agosuite.jsp</a> This data is available in 1:1M tiles or as a full continental Mosaic. Tiles areas are available at: <a href="http://www.ga.gov.au/acres/prod_ser/agotilemap.jsp">http://www.ga.gov.au/acres/prod_ser/agotilemap.jsp</a>

  • The RADARSAT Data Products Specification provides and overview of the endorsed products generated by the RADARSAT program. These products may be produced at the CDPF or at any of the RADARSAT network stations.

  • The product SAR.PRI is a digital image generated from raw SAR data using up-to-date auxiliary parameters, corrected for antenna elevation gain and range spreading loss. The image, projected on ground range, covers an area of 1400km wide and at least 102.5 km long. The ESA SAR.PRI format is based on the grneral definition of the SAR CEOS format (ref. ER-IS-EPO-GS-5902.

  • The product SAR.GTC is a digital image generated from raw SAR data takes using up-tp-date auxiliary parameters, with the best available instrumental corrections applied, precisely located, corrected for terrain varieations and rectified onto a map projection. The ESA SAR.GTC format is based on the general definition of the SAR CEOS format (ref. ER-IS-EPO-GS-5902).

  • The product SAR.SLC is a single look complex digital image generated from raw SAR data using up-to-date auxiliary parameters. The image, projected on sland range, referred to as 'quarter scene' or quadrant corresponds to approximately one half (range) by one half (azimuth) of a full scence image. The ESA SAR.SLC format is based on the general definition of the SAR CEOS format (ref. ER-IS-EPS-GS-5902).

  • The product SAR.GEC is a digital image generated from raw SAR data takes using up-to-date auxiliary parameters, with the best available instrumental corrections applied, precisely located and rectified onto a map projection. The JERS SAR.GEC format is based on the general definition of the SAR CEOS format (ref. ER-IS-EPO-GS-5902).

  • This document defines the Computer Compatible Tape (CCT) format for raw, quicklook, bulk-corrected (georeferenced) system-corrected and precision processed Landsat Thematic Mapper (TM) imagery data acquired from the Landsat 4, Landsat 5 and subsequent satellites.