Changeset 3402 for production/onslow_2006/report/data.tex

Timestamp:

Jul 21, 2006, 5:28:16 PM (19 years ago)

Author:

sexton

Message:

incorporating Trevor Dhu's comments

File:

• production/onslow_2006/report/data.tex (modified) (6 diffs)

production/onslow_2006/report/data.tex

@@ -1 @@
-The calculated run-up height and resulting inundation ashore is determined by
+The calculated run-up height and resulting inundation ashore is controlled by
 the input topographic and bathymetric elevation, the
 initial and boundary conditions, as well as the cell area of the computational
 mesh. 
-Ideally, the data should adequately capture all complex features
+Ideally, the topographic and bathymetric data
+should adequately capture all complex features
 of the underlying bathymetry and topography. Any limitations
 in the resolution and accuracy of the data will introduce 
@@ -14 +15 @@
 and Lowest Astronomical Tide (LAT) defined as 1.5m AHD
 and -1.5m AHD respectively for Onslow \cite{antt:06}. 
-These values are tidal
-predictions based on continous tidal observations from Standard Ports
-over a period of
-at least one year, with the Australian Hydrographic Service
-recommending this be extended to three years to capture
-changes to the mean sea level. Onslow is listed as
-a Standard Port. As an aside, current work at GA is
+As an aside, current work at GA is
 extracting information from LANDSAT imagery to reconstruct the 
 tidal variations for various WA locations. Future modelling of
@@ -36 +31 @@
 DLI data is distorted by vegetation and buildings.  
 
+With respect to the offshore data, the Department of Planning and
+Infrastructure (DPI) have provided state digital fairsheet data around
+Onslow. This data covers a very small geographic area. 
+Similar data have been provided by DPI for Pt Hedland and Broome.
+The Australian Hydrographic Office (AHO) has supplied extensive
+fairsheet data which has also been utilised. In contrast to the onshore data, 
+the offshore data is a series of survey points which is typically 
+not supplied on a fixed grid. In addition, offshore data typically 
+does not have the coverage of the onshore data, and often the 
+offshore data will have gaps where surveys have not been conducted.
+The coastline has been generated by
+using the aerial photography, two detailed surveys provided
+by WA DPI and a number of total station surveys \footnote{Total station survey information
+has been used to verify the elevation data. A total station is an
+electronic device that combines the ability to measure a position 
+horizontally and vertically at the same time.} of Onslow. 
+The WA DLI data surrounding the coast are error prone and
+have been clipped at the derived coastline. 
+
 Figure \ref{fig:contours_compare}(a) shows the contour lines for
 HAT, MSL and LAT for Onslow using the DTED data where it is evident 
@@ -41 +55 @@
 parts of Onslow town appears to be inundated at HAT before a tsunami has
 even been generated. This is due to
-short comings with the digital elevation model (DEM) created from 
+shortcomings with the digital elevation model (DEM) created from 
 the DTED data. 
 Figure \ref{fig:contours_compare}(b) shows
 the contour lines for HAT, MSL and LAT for Onslow using the WA DLI data.
 It is obvious that there are significant differences in each DEM with
-total station survey information and the knowledge
+the total station survey information and the knowledge
 of the HAT contour line pointing to increased confidence in the WA DLI
 data over the DTED data for use in the inundation modelling.
-The impact difference based on these two onshore data sets 
-will be discussed in Section \ref{sec:issues}.
+Consequently the DLI data has been used in this study.
 
 
@@ -75 +88 @@
 \end{figure}
 
-With respect to the offshore data, the Department of Planning and
-Infrastructure (DPI) have provided state digital fairsheet data around
-Onslow. This data cover only a very small geographic area. (Note,
-similar data have been provided by DPI for Pt Hedland and Broome.) 
-The Australian Hydrographic Office (AHO) has supplied extensive
-fairsheet data which has also been utilised. In contrast to the onshore data, the offshore data is a series of survey points which is typically not supplied on a fixed grid. In addition, offshore data typically does not have the coverage of the onshore data, and often the offshore data will have gaps where surveys have not been conducted.
-The coastline has been generated by
-using the aerial photography, two detailed surveys provided
-by WA DPI and a number of total station surveys of Onslow. 
-The WA DLI data surrounding the coast are error prone and
-have been clipped at the derived coastline. 
+
 Appendix \ref{sec:metadata} provides more details and the supporting metadata 
 for this study, including images of the data extent.
@@ -95 +98 @@
 \begin{center}
 \begin{tabular}{|l|l|}\hline
-Data & Detail \\ \hline 
+Data & Specifications \\ \hline 
 DIGO DTED Level 2  & Onshore, 1 second $\approx$ 30m \\ \hline 
 DLI & Onshore, 20m DEM and orthophotography \\ \hline