source: production/pt_hedland_2006/report/anuga.tex @ 3157

The software tool, ANUGA \cite{ON:modsim}, has been used to develop the inundation extent
and associated water height at various points in space and time.
ANUGA has been developed by GA and the Australian National University
(ANU) to solve the nonlinear shallow water
wave equation using the finite volume technique.
An advantage of this technique is that the cell area can be changed
according to areas of interest and that wetting and drying
is treated robustly as part of the numerical scheme. 
ANUGA is continually being developed and validated.
As such, the current results represent ongoing work
and may change in the future.

The following set of information is required to undertake the tsunami
inundation modelling;.

\begin{itemize}
\item onshore and offshore elevation data (topographic and bathymetric data, 
see Section \ref{sec:data})
\item initial condition (e.g. determined by tides)
\item boundary condition (the tsunami source as described in 
Section \ref{sec:tsunami_scenario})
\end{itemize}

This is because ANUGA calculates whether each cell in the triangular
mesh is wet or dry and does not consider partially wetted cells. 
It is important
to refine the mesh to be commensurate with the underlying data especially in 
those regions where complex behaviour will occur, such as the inter-tidal
zone and estuaries.

In modelling the tsunami wave in deep water, 
it is suggested that the minimum model resolution 
be such so that there are at least
ten cells per wavelength (this usually refers to modelling in a finite
difference environment which typically work on a fixed grid). The modelling
undertaken to develop the preliminary hazard map typically used a 
resolution of blah m as sunamis typically have very long wavelengths.