Script based groundwater modelling for increased model flexibility and improved analysis

• Main Authors: Vilhelmsen, Troels Norvin, Christensen, Steen, Frederiksen, Rasmus Rumph, Auken, Esben, Fienen, Michael N., Leaf, Andrew
• Format: Conference Object
• Language: English
• Published: 2018
• Subjects: Bakker; Greenland; Jupiter; Ropen
• Online Access: https://pure.au.dk/portal/da/publications/script-based-groundwater-modelling-for-increased-model-flexibility-and-improved-analysis(e7db823e-34c8-4ced-b1fb-949eb033c32e).html; http://www.danishwaterforum.dk/Research/Annual_meeting_2018/DWF%20annual%20water%20research%20conference%2030%20january%202018.pdf

Recently, script-based methods to setup, run and post-process groundwater models have been developed to support MODFLOW and related USGS modelling programs (Bakker et al., 2016). Script-based modeling can improve efficiency, quality and repeatability in the development and analysis of hydrological models. In the rOpen project we seek to expand and modify the framework developed by Bakker et al. (2016), such that it can be used for high-resolution analysis of nitrate leaching from agricultural areas in Denmark. However, to make such analyses cost efficient on large (e.g. national) scale requires development of new modeling methods. In this presentation we will show how Danish data sources such as Jupiter and Gerda databases (Møller et al., 2009), high resolution digital elevation models (DEM), DMI climate, data and GIS information on land use, streams, and catchment areas can be used in this framework to develop groundwater models. The geophysical and lithological data will mainly be utilized for setting up the subsurface structures. These structures will be defined based on the newly developed tTEM system, which produces high-resolution resistivity models of the subsurface. The DEM will be used to define layer elevations, flow directions, and streamflow networks. Recharge estimates will be determined using the Daisy root-zone model (Abrahamsen and Hansen, 2000). Existing GIS data will be used to define the model outline, location of additional boundary conditions and specifications of practices and land use on the surface. All of the data sources going into the modeling environment will be independent of the finite difference grid used in the numerical model, to facilitate subsequent modifications to the horizontal numerical resolution or the number of layers in the model. This is simply done by resampling the data sources to a new finite difference grid with a different resolution. Based on this methodology, general frameworks can be generated for setting up models. Site dependent modifications can then be made to these frameworks to make the setups applicable in other areas. This will allow for faster model development, which can be updated more easily with new data collection. [e-mail]: Aarhus University, Hydrogeophysics Group, C.F. Møllers Allé 4, DK-8000 Aarhus C, Denmark [e-mail]: Aarhus University, dep of Geoscience, Høegh-Guldbergs Gade 2, DK-8000 Aarhus C, Denmark [e-mail]: Aarhus University, Hydrogeophysics Group, C.F. Møllers Allé 4, DK-8000 Aarhus C, Denmark [e-mail]: USGS Upper Midwest Science Center 8505 Research Way Middleton, WI 53562, USA [e-mail]: USGS Upper Midwest Science Center 8505 Research Way Middleton, WI 53562, USA [e-mail]: Aarhus University, Hydrogeophysics Group, C.F. Møllers Allé 4, DK-8000 Aarhus C, Denmark References: Abrahamsen, P. and Hansen, S., 2000. Daisy: an open soil-crop-atmosphere system model. Environmental Modelling & Software, 15(3): 313-330. Bakker, M., Post, V., Langevin, C.D., Hughes, J.D., White, J.T., Starn, J.J. and Fienen, M.N., 2016. Scripting MODFLOW Model Development Using Python and FloPy. Groundwater. Møller, I., Søndergaard, V.H. and Jørgensen, F., 2009. Geophysical methods and data administration in Danish groundwater mapping. Geological Survey of Denmark and Greenland Bulletin, 17: 41-44.