[2950] | 1 | The calculated run-up height and resulting inundation ashore is determined by |
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[3064] | 2 | the input topographic and bathymetric elevation, the forcing terms, the |
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| 3 | initial and boundary conditions, as well as the cell area of the computational |
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| 4 | mesh. |
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| 5 | Ideally, the data should adequately capture all complex features |
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| 6 | of the underlying bathymetry and topography and that mesh |
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[3098] | 7 | is commensurate with the underlying data, as discussed in |
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[3138] | 8 | Section \ref{sec:anuga}. Any limitations |
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[3064] | 9 | in the resolution and accuracy of the data will introduce |
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[3098] | 10 | errors to the inundation maps, in addition to the range of approximations |
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| 11 | made within the model. |
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[2950] | 12 | |
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[3064] | 13 | Data for this study have been sourced from a number of agencies. With |
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[2950] | 14 | respect to the onshore data, the Defence Imagery and Geospatial |
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| 15 | Organisation (DIGO) supplied the DTED (Digital Terrain Elevation |
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| 16 | Data) Level 2 data which has been authorised for Australian Tsunami |
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| 17 | Warning System use only. This data has a resolution of 1 second |
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| 18 | (about 30 metres), produced from 1:50 000 contours, elevations and |
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[3064] | 19 | drainage. In addition, the Department of Land Information (DLI) has provided a |
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[3188] | 20 | 20m Digital Elevation Model (DEM) and orthophotography |
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[3252] | 21 | covering the NW Shelf. The DTED Level 2 data is ``bare earth'' with |
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| 22 | the DLI data is distored by vegetation and buildings. The WA DLI data |
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[3268] | 23 | is used for the simulation results which follow, due to its overall |
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| 24 | increased accuracy over the DTED data. Further discussion on the comparison |
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[3252] | 25 | between these data sets is deferred to Section \ref{sec:issues}. |
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| 26 | %However, the 30m |
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| 27 | %DTED Level 2 data is ``bare earth'' whereas the DLI data is distorted by |
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| 28 | %vegetation |
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| 29 | %and buildings so we have chosen to use the DTED as the onshore |
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| 30 | %topographic data set. It is also important to note that the DEM does |
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| 31 | %not include features such as rock walls, berths etc. |
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[2950] | 32 | |
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| 33 | With respect to the offshore data, the Department of Planning and |
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[3064] | 34 | Infrastructure (DPI) have provided state digital fairsheet data around |
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[2950] | 35 | Onslow. This data covers only a very small geographic area. (Note, |
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[3064] | 36 | similar data has been provided for Pt Hedland and Broome by DPI.) |
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| 37 | The Australian Hydrographic Office (AHO) has supplied extensive |
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[3252] | 38 | fairsheet data which has also been utilised. |
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[3267] | 39 | The coastline has been generated by |
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[3285] | 40 | using the aerial photography, two detailed surveys provided |
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| 41 | by WA DPI and a number of total station surveys of Onslow. |
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| 42 | The WA DLI data surrounding the coast is error prone and |
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| 43 | has been clipped at the derived coastline. |
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[3267] | 44 | Appendix \ref{sec:metadata} provides more details and metadata for data |
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[3252] | 45 | used for this study. |
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| 46 | Table \ref{table:data} summarises the available data for this study. |
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[2950] | 47 | |
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[3252] | 48 | \begin{table} |
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[3270] | 49 | \caption{Available data for the North West shelf tsunami inundation studies.} |
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[3252] | 50 | \label{table:data} |
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[2950] | 51 | \begin{center} |
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| 52 | \begin{tabular}{|l|l|}\hline |
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| 53 | Data & Detail \\ \hline |
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| 54 | DIGO DTED Level 2 & Onshore, 1 second $\approx$ 30m \\ \hline |
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| 55 | DLI & Onshore, 20m DEM and orthophotography \\ \hline |
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| 56 | DPI & Offshore, fairsheet data around Onslow \\ \hline |
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[3064] | 57 | AHO & Offshore, fairsheet data for North West Shelf region \\ \hline |
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[2950] | 58 | \end{tabular} |
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| 59 | \end{center} |
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[3253] | 60 | \end{table} |
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[2950] | 61 | |
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[3169] | 62 | %\begin{figure}[hbt] |
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| 63 | % |
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| 64 | % \centerline{ \includegraphics[width=100mm, height=75mm] |
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| 65 | %{../report_figures/onslow_data_extent.png}} |
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| 66 | % |
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| 67 | % \caption{Data extent for Onslow scenario. Offshore data shown in blue |
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| 68 | %and onshore data in green.} |
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| 69 | % \label{fig:onslowdataarea} |
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| 70 | %\end{figure} |
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[2950] | 71 | |
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| 72 | |
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[3252] | 73 | |
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