[4114] | 1 | Title: Computational Modelling of Hydrological Impacts - Open source software developed by the Australian Federal Government. |
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| 3 | |
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| 4 | Speaker: |
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| 5 | Ole Nielsen, Geoscience Australia |
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| 6 | Ole.Nielsen@ga.gov.au |
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| 7 | |
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| 8 | |
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| 9 | Modelling the effects on the built environment of natural hazards such |
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| 10 | as riverine flooding, storm surges and tsunami is critical for |
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| 11 | understanding their economic and social impact on our urban |
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| 12 | communities. Geoscience Australia and the Australian National |
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| 13 | University have developed a hydrodynamic inundation modelling tool |
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| 14 | called ANUGA to help simulate the impact of these hazards. |
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| 16 | |
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| 17 | The core of ANUGA is a Python implementation of a finite-volume method |
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| 18 | for solving the conservative form of the Shallow Water Wave equation. |
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| 19 | This method allows the study area to be represented by an unstructured |
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| 20 | mesh with variable resolution to suit the particular problem. The |
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| 21 | conserved quantities are water level (stage) and horizontal momentum. |
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| 22 | An important capability of ANUGA is that it can robustly model the |
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| 23 | process of wetting and drying as water enters and leaves an area. This |
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| 24 | means that it is suitable for simulating water flow onto a beach or |
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| 25 | dry land and around structures such as buildings. |
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| 26 | |
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| 27 | To set up a particular scenario the user generates a mesh with regions |
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| 28 | and boundary segments identified by symbolic tags used to bind values |
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| 29 | to arbitrary functions supplied during the simulation. In addition, |
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| 30 | all quantities may be assigned or updated by supplying either constant |
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| 31 | values, arbitrary functions or general expressions combining existing |
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| 32 | quantities. Arbitrary forcing terms such such as wind stress or |
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| 33 | atmospheric pressure gradients may also be supplied. While this |
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| 34 | interface provides great flexibility due to Python's object model, |
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| 35 | dynamic typing and constructs such as generators, the computationally |
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| 36 | intensive components are written for efficiency in the C language |
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| 37 | working directly with the Numerical Python structures. |
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| 38 | |
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| 39 | ANUGA has recently been released as Open Source. This strategy will enable |
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| 40 | free access to the software and allow the risk research community to |
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| 41 | use, validate and contribute to the software in the future. |
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| 42 | |
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| 43 | The talk outlines the model implementation, provides validation |
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| 44 | results, identifies remaining challenges and describes ANUGA's role within |
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| 45 | the Australian Tsunami Warning System. |
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| 46 | |
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