1. www.wldelft.nl June 12 th 2007 Storing data for integrated 1D, 2D, 3D models of rivers, estuaries and seas Bert Jagers

2. www.wldelft.nl general intro Delft Hydraulics Independent research foundation since 1927 about 300 people research and expert advise projects worldwide: Europe, Asia (Japan, Hong Kong, Singapore, China, Middle East, …), Africa (Egypt, South Africa, …), America (USA, Panama, …), Australia numerical simulation models and operational systems

3. www.wldelft.nl modelling system 1 Delft3D: Windows & Linux, parallel Characteristics: 2D or 3D curvilinear model Multi-domain (multi-tile), sigma- or z-layer Application areas: ocean, sea, coast, estuary, river Hydrodynamics, waves, meteorological forcing Morphodynamics, stratigraphy Ecology, water quality Many users around the world: research institutes, universities, and consultants

4. www.wldelft.nl Delft3D from global scale modelling … Aceh earthquake, Dec ‘04

5. www.wldelft.nl

6. … and long time scales … 50 – 1000 years

7. www.wldelft.nl … via storm surge predictions … Typhoon Frankie Vietnam (’96)

8. www.wldelft.nl … to detailed engineering studies … Dubai 10 m – 10 km, 1 hour – 10 years

9. www.wldelft.nl … and flume experiments

10. www.wldelft.nl netCDF/CF issues Curvilinear, multi-tile, clipped coordinates Staggered Arikawa-C style scheme: storing restart data versus generic output

11. www.wldelft.nl netCDF/CF issues Local features: weirs, dykes, dams, bridges, … Staggered Arikawa-C style scheme: data located at cell centres, cell interfaces and some at the original grid points

12. www.wldelft.nl GIS integration preprocessing: grid generation data interpolation feature mapping

13. www.wldelft.nl GIS integration postprocessing online visualisation netCDF support by GIS systems (ArcGIS 9.2) will it be CF aware?

14. www.wldelft.nl netCDF/CF issues regional models: 1) use coordinate systems of local data providers (grid mapping) & keep track of coordinate system used throughout modelling system 2) use global coordinates (like netCDF/CF) & use GIS for the projections (keep track of accuracy for local detailed models!) Dutch part  German part  deal with vertical datums Dutch NAP = Belgian TAW + 2.32 m

15. www.wldelft.nl Generalised sigma, mixed sigma-z-coordinates: extra vertical coordinate options netCDF/CF issues Aggregation table: data provided on irregular “subgrid”

16. www.wldelft.nl … to be integrated with …

17. www.wldelft.nl modelling system 2 SOBEK : Windows & Linux Characteristics: integrated 2D & 1D (open channel & sewer) Multi-domain (multi-tile) Application areas: river, rural, urban Hydrology, hydrodynamics, groundwater Morphodynamics, real-time control Emissions, ecology, water quality Many users around the world: research institutes, universities, and consultants

18. www.wldelft.nl overlap with Delft3D applications 1D channels and levees 2D plains flooding, shallow lakes, …

19. www.wldelft.nl regional scale applications albufera lake melbourne

20. www.wldelft.nl flood early warning systems from meteo data to flood prediction (as local as realistically possible) operational aspects: 24 hours, 7 days per week distributed data access

21. www.wldelft.nl netCDF/CF issues Again Multi-tile, staggered scheme Regional models, coordinate systems, GIS integration Additional Combined 1D-2D, cross-sections Naming conventions (water level in pipe = sea_surface_height_above_geoid?)

22. www.wldelft.nl … gives an generally unstructured code …

23. www.wldelft.nl netCDF/CF issues How to store unstructured grids and the associated data?  finite volume approach: distinguish volumes & fluxes multiple associated GIS expressable one grid one topology data location sets Why not use the same approach for LRG?

24. www.wldelft.nl the end Questions? bert.jagers@wldelft.nl