1 | Title: Computational Modelling of Hydrological Impacts - Open source software developed by the Australian Federal Government. |
---|
2 | |
---|
3 | |
---|
4 | Speaker: |
---|
5 | Ole Nielsen, Geoscience Australia |
---|
6 | Ole.Nielsen@ga.gov.au |
---|
7 | |
---|
8 | |
---|
9 | Modelling the effects on the built environment of natural hazards such |
---|
10 | as riverine flooding, storm surges and tsunami is critical for |
---|
11 | understanding their economic and social impact on our urban |
---|
12 | communities. Geoscience Australia and the Australian National |
---|
13 | University have developed a hydrodynamic inundation modelling tool |
---|
14 | called ANUGA to help simulate the impact of these hazards. |
---|
15 | |
---|
16 | |
---|
17 | The core of ANUGA is a Python implementation of a finite-volume method |
---|
18 | for solving the conservative form of the Shallow Water Wave equation. |
---|
19 | This method allows the study area to be represented by an unstructured |
---|
20 | mesh with variable resolution to suit the particular problem. The |
---|
21 | conserved quantities are water level (stage) and horizontal momentum. |
---|
22 | An important capability of ANUGA is that it can robustly model the |
---|
23 | process of wetting and drying as water enters and leaves an area. This |
---|
24 | means that it is suitable for simulating water flow onto a beach or |
---|
25 | dry land and around structures such as buildings. |
---|
26 | |
---|
27 | To set up a particular scenario the user generates a mesh with regions |
---|
28 | and boundary segments identified by symbolic tags used to bind values |
---|
29 | to arbitrary functions supplied during the simulation. In addition, |
---|
30 | all quantities may be assigned or updated by supplying either constant |
---|
31 | values, arbitrary functions or general expressions combining existing |
---|
32 | quantities. Arbitrary forcing terms such such as wind stress or |
---|
33 | atmospheric pressure gradients may also be supplied. While this |
---|
34 | interface provides great flexibility due to Python's object model, |
---|
35 | dynamic typing and constructs such as generators, the computationally |
---|
36 | intensive components are written for efficiency in the C language |
---|
37 | working directly with the Numerical Python structures. |
---|
38 | |
---|
39 | ANUGA has recently been released as Open Source. This strategy will enable |
---|
40 | free access to the software and allow the risk research community to |
---|
41 | use, validate and contribute to the software in the future. |
---|
42 | |
---|
43 | The talk outlines the model implementation, provides validation |
---|
44 | results, identifies remaining challenges and describes ANUGA's role within |
---|
45 | the Australian Tsunami Warning System. |
---|
46 | |
---|