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  • Eddy Covariance (EC) is considered a key atmospheric technique for quantifying CO2 leakage. However the complex and localised heterogeneity of a CO2 leak above the background environmental signal violates several of the critical assumptions made when implementing the EC technique, including: - That horizontal gradients in CO2 concentration are zero. - That horizontal and vertical gradients in the covariance of CO2 and orthogonal wind directions are zero. The ability of EC measurements of CO2 flux at the surface to provide information on the location and strength of CO2 leakage from below ground stores was tested during a 144 kg/day release event (27 March - 13 June 2012) at the Ginninderra controlled release facility. We show that the direction of the leak can be ascertained with some confidence although this depends on leak strength and distance from leak. Elevated CO2 levels are seen in the direction of the leakage area, however quantifying the emissions is confounded by the potential bias within each measurement through breaching of the assumptions underpinning the EC technique. The CO2 flux due to advection of the horizontal CO2 concentration gradients, thought to be the largest component of the error with the violation of the EC technique's assumptions, has been estimated using the modelling software Windtrax. The magnitude of the CO2 flux due to advection is then compared with the measured CO2 flux measured using the EC technique, to provide an initial assessment of the suitability of the EC technique to quantifying leakage source rates.

  • Here we demonstrate a workflow for the development of a local, corrected wind field for severe Tropical Cyclone (TC) Debbie. We combine modelling with corrections based on observations, and local wind effects including topography, land cover, shielding and direction to provide the best estimate of actual wind speeds. This is important, as wind speed observations are sparse, and do not necessarily provide even coverage of the TC landfall region. The final corrected wind field records the maximum 0.2 second wind gust, at 10 metres above ground, throughout the lifetime of TC Debbie, and provides a best estimate of maximum wind gust speeds associated with TC Debbie. Through the development of this workflow we will demonstrate the importance of observational data for validating wind field modelling outputs, and highlight the usefulness of James Cook University’s mobile anemometers for collecting wind speed data where gaps exist in the Bureau of Meteorology’s automatic weather station network. We identify the limitations in the availability of national land cover datasets at high resolution, and demonstrate the development of a fit-for-purpose land cover dataset using GA’s Digital Earth Australia Landsat archives (Lewis et al. 2017). This report and the accompanying datasets have been released with the aim of showcasing a method, which can be refined by others to develop a standard methodology for the production of local TC wind fields. This workflow can be applied in the same way following future TC events to support the post-disaster field surveys that are routinely carried out by a range of parties following a severe TC making landfall. The local wind fields, combined with the damage surveys ultimately help to refine our vulnerability models of housing stock in Australia.

  • As part of the controlled release experiments at the Ginninderra test site, an eddy covariance (EC) flux tower was installed. The aim was to determine whether EC was an effective technique for detecting, locating and quantifying CO2 emissions from a leak. The results of this study suggest that EC can be used for leak detection, but application of the technique for quantification exposes problems in the underlying assumptions when dealing with heterogeneous localised leakage systems. The EC tower identified elevated CO2 fluxes from the direction of the leak during the release experiment. The median background CO2 flux from the field was 0.63 ?mol/m2/s, while median leakage CO2 fluxes ranged from 4.57 - 9.11 ?mol/m2/s based on proximity of wind directions to the leak. Once the controlled release stopped, CO2 fluxes from the leak direction quickly returned to background levels.

  • A metadata report for the atmospheric monitoring station installed in Arcturus, south of Emerald in central Queensland. The station was installed for baseline atmospheric monitoring to contribute to emission modelling spanning 2010-2014. The station included compositional gas analysers, supporting meteorological sensors and an eddy covariance flux tower. The metadata covered in the report include: the major variables measured by each instrument, the data duration and frequency, data accuracy, calibration and corrections, the location the data is stored, and the primary contact for the data.

  • To provide the solar power industry with a data resource to allow them to assess the economic potential of a site for a solar power plant. Specifically under the Solar Flagship program.

  • Hourly direct normal solar exposure is the total amount of direct beam solar energy falling over one hour on a surface whose orientation is maintained perpendicular to the solar beam. Typical values for hourly direct normal exposure range up to around 3 MJ/m2 (megajoules per square metre). The values are usually highest in clear skies and decrease rapidly with increasing cloudiness, and also decrease to a lesser extent with increasing haziness and decreasing solar elevation. Global solar exposure is the total amount of solar energy falling on a horizontal surface. The daily global solar exposure is the total solar energy for a day. Typical values for daily global exposure range from 1 to 35 MJ/m2 (megajoules per square metre). For mid-latitudes, the values are usually highest in clear sun conditions during the summer and lowest during the winter or very cloudy days. See LINEAGE below for more information.

  • Global solar exposure is the total amount of solar energy falling on a horizontal surface. The hourly global solar exposure is the total solar energy for one hour. Typical values for hourly global exposure range up to 4 MJ/m2 (megajoules per square metre). The values are usually highest in the middle of the day and around summer, with localised variations caused mainly by variations in atmospheric conditions, primarily cloudiness. See metadata statement for more information.

  • As part of the 2018 Tropical Cyclone Hazard Assessment (TCHA), we compiled the geospatial raster dataset that can be accessible to internal and external users via ArcGIS online and can be integrated for building additional geoprocessing applications. This web service gives more stable and easy access to data and interactive maps. With having separate geospatial layers for each recurrence interval- i.e. 5 through 10000 years, users can toggle between the layers and evaluate the changes in wind speed (km/hr) and potential areas at risk on the fly.

  • The Tropical Cyclone Scenario Selector Tool (TC SST) provides an interactive application to interrogate the stochastic event catalogue which underpins the 2018 Tropical Cyclone Hazard Assessment (TCHA18). The application allows users to search for TC events in the catalogue based on location and intensity (either TC intensity category, or maximum wind speed), visualise the tracks and the wind fields of those events, and download the data for further analysis.