<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>

A mini-poster on GA's capability in tsunami hazard modelling.

A new methodology is proposed to estimate storm demand and dune recession by clustered and non-clustered events, to determine if the morphological response to storm clusters results in greater beach erosion than that from individual storms that have the same average recurrence interval (ARI) or return period. The method is tested using a numerical morphodynamic model that combines both cross-shore and longshore beach profile evolution processes, forced by a 2D wave transformation model, and is applied as an example within a 20 km long coastal cell at an erosion hotspot at Old Bar, NSW mid-north coast, Australia. Wave and water level data hindcast in previous modelling (Davies et al., 2017) were used to provide two thousand different synthetic wave and tide records of 100 years duration for input to a nested nearshore 2D SWAN model that provides wave conditions at the 12 m depth contour. An open-source shoreline evolution model was used with these wave conditions to model cross-shore and longshore beach profile evolution, and was calibrated and verified against long-term dune recession observations. After a 50 year model spin up, 50 years of storm demand (change in sub-aerial beach volume) and dune toe position were simulated and ranked to form natural estimators for the 50, 25, 16, 12.5 and 10 year return period of individual events, together with confidence limits. The storm demand analysis was then repeated to find the return period of clustered and non-clustered morphological events. Morphological clusters are defined here by considering the response of the beach, rather than the forcing, with a sensitivity analysis of the influence of different recovery thresholds between storms also investigated. The new analysis approach provides storm demand versus return period curves for the combined population of clustered and non-clustered events, as well as a curve for the total population of individual events. In this approach, non-clustered events can be interpreted as the response to isolated storms. For clustered and non-clustered morphological events the expected storm demand for a 50-year return period is approximately 25% greater than that for individual events. Alternatively, for clustered and non-clustered events the magnitude of the storm demand that occurs at a return period of 17 years is the same as that which occurs at a return period of 50 years for individual events. However, further analysis shows that for a 50-year return period, the expected storm demand for the population of non-clustered events is similar to that of the clustered events, although the size of the population of the latter is much greater. Hence, isolated storms can generate the same storm demand as storm clusters, but there is a much higher probability that a given storm demand is generated by a morphologically clustered event. Appeared online in Coastal Engineering Volume 168, September 2021.

The Northern Approaches to Broome multibeam survey was acquired for the Australian Hydrographic Office (AHO) onboard the MV Bhagwan K during the period 05 August– 02 October 2020. This was a contracted survey conducted by EGS as part of the Hydroscheme Industry Partnership Program. The survey area encompasses the northern approaches to Broome, WA located between the Talboys Rock and Gantheaume Point, Western Australia. Bathymetry data was acquired using a Kongsberg EM2040D 200-400 kHz and processed using QPS QINSy 9.2.3 processing software. The dataset was then exported as a 30m resolution, 32 bit floating point GeoTIFF grid of the survey area. <BR>This dataset is not to be used for navigational purposes.

The Great North Channel Torres Strait Multibeam survey was acquired for the Australian Hydrographic Office (AHO) onboard the MV Offshore Guardian and MV Special Order during the period 04 February– 14 April 2021. This was a contracted survey conducted by Guardian Geomatics as part of the Hydroscheme Industry Partnership Program. The survey area encompasses the Great North East Channel of the Torres Strait located between the Stephens Island, Pearce Cay and Rennel Island, Queensland. Bathymetry data was acquired using a Kongsberg EM2040-07 and Norbit iWBMSh Stx 200-400 kHz and processed using CARIS HIPS & SIPS 11.3 processing software. The dataset was then exported as a 30m resolution, 32 bit floating point GeoTIFF grid of the survey area. <BR>This dataset is not to be used for navigational purposes.

<div>The Banks Strait Reference Surfaces bathymetry survey was acquired for the Australian Hydrographic Office (AHO) on 17 Dec 2021. This surface was created from a contracted national reference survey within Banks Strait to Cape Barren, TAS, collected for the purpose of calibrating multibeam echosounders.&nbsp;It was conducted for the Australian Hydrographic Office as part of the Hydroscheme Industry Partnership Program, acquired using Kongsberg EM 2040 MkII and Kongsberg EM 2040P, and processed using QPS Qimera. A grid in 0.5m resolution is provided for the surveyed site within this survey area in MSL, LAT and Ellipsoid vertical datum. The dataset was then exported as a 0.5m resolution, 32 bit floating point GeoTIFF grid of the survey area.</div><div>This dataset is not to be used for navigational purposes.</div>

The Solitary Islands Gumbaynggirr Yaegl MP bathymetry survey was acquired by the NSW government (Department of Planning and Environment – DPE) onboard the RV Bombora during the period 31 Aug 2022 – 31 Jul 2023, using DPE’s R2Sonic 2022 multibeam sonar. The survey was completed as part of the SeabedNSW program funded by NSW government through Coastal Reforms (>2015), HabMap Program funded through Marine Parks Authority (now under Marine Estate Management Authority) or through collaborations with partner agencies or institutions. The purpose of the project was to 1) provide a baseline dataset and 2) map the spatial distribution of seabed types. This dataset contains 32-bit floating point geotiff files of bathymetry and backscatter in 5m resolution for the study area, derived from the processed Hypack, R2Sonic GUI, POSView, POSPac, Qimera and FMGT software. General details on vessel setup, mobilisation and processing are provided at https://www.environment.nsw.gov.au/-/media/OEH/Corporate-Site/Documents/Research/Our-science-and-research/seabed-nsw-standard-operating-procedures-multibeam-surveying-190101.pdf with survey specific details in the Survey Report and DPIE Rigor Statement (can be provided upon request). This dataset is not to be used for navigational purposes.

<div>The Banks Strait to Cape Barren bathymetry survey was acquired for the Australian Hydrographic Office (AHO) onboard the MV Offshore Solution during the period 29 November 2021 – 19 April 2022. This was a contracted survey conducted for the Australian Hydrographic Office by Ocean Infinity Australia as part of the Hydroscheme Industry Partnership Program. The survey area encompases an area within Banks Strait to Cape Barren, Tasmania. Bathymetry data was acquired using a Kongsberg EM2040 MKII and a Kongsberg EM2040P, and processed using QPS Qimera processing software. 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 Camden Sound (North-West) bathymetry survey was acquired for the Australian Hydrographic Office (AHO) onboard the MV Ocean Dynasty and MV Empress during the period 21 September 2021 – 9 Jan 2022. This was a contracted survey conducted for the Australian Hydrographic Office by MMA Offshore as part of the Hydroscheme Industry Partnership Program. The survey area encompases an area North West of Camden Sound, Western Australia. Bathymetry data was acquired using a Kongsberg EM2040P Mk II and processed using QPS Qimera V2.0.1 processing software. 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 Flinders Island bathymetry survey was acquired for the Australian Hydrographic Office (AHO) onboard the MV Offshore Surveyor during the period 16 December – 13 May 2022. This was a contracted survey conducted for the Australian Hydrographic Office by Guaridan Geomatis Pty Ltd as part of the Hydroscheme Industry Partnership Program. The survey area encompases an area North East of Flinders Island, Tasmania. Bathymetry data was acquired using a Kongsberg EM2040-07 MKII and processed using CARIS HIPS & SIPS processing software. 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>