Long term coastal datasets – What else have we been measuring?

Mr John Ryan1, Mr Jim Waldron1, Mr Daryl Metters1

1Department Of Environment And Science, Deagon, Australia

Abstract:

The Queensland Government Hydraulics Laboratory (QGHL) monitors storm tide and ocean waves in Queensland coastal waters for use during extreme events and for modelling and forecasting of such events. Storm tide gauges measure water level for monitoring storm surge. After the 2004 Sumatra Tsunami there was a focus on monitoring Tsunami and the QGHL upgraded the instrumentation to one-minute sampling so that Tsunami could be identified. Initially, we didn’t know the storm tide gauge sites were measuring Meteotsunami and It was discovered that Meteorological Tsunami were also inherently embedded in the data after pressure sensors were added to monitor pressure changes during extreme events. Waverider buoys are seen by many to be one of the most reliable means of accurately recording ocean waves. QGHL has been using Waveriders as part of its coastal monitoring program since 1968 with the purpose of quantifying the ocean wave climate. As part of an investigation into coastal impacts of ship wake, the QHGL was motivated to revisit data collected by its fleet of Waverider buoys. Ship wake has been of interest since the time of Lord Kelvin, more recently, with the emergence of larger, faster vessels, the increased impact of ship wake on shoreline erosion especially in shallow or confined waterways has become a source of concern for coastal planners. Current investigations of vessel wake usually involve pressure sensors, or radars. By applying a spectrogram to water surface elevations recorded by Waverider buoys, when conditions were favourable QGHL detected vessel wake, in data from several wave monitoring sites. This paper describes how two previously unknown parameters within the current storm tide and wave monitoring datasets are now being quantified.


Biography:

John Ryan is a Principal Scientist in the Queensland Government Hydraulics Laboratory, Department of Environment & Science. John has a Bachelor of Engineering degree in Mechanical Engineering. John has managed the storm tide and wave monitoring networks for the last 10 years. John has worked in a number of different fields: exploration drilling, copper smelter, metal tube pipe cutting systems and wireless internet services.