Dr. Helena Mitasova, Geographic Modeling Systems Lab., University of Illinois at Urbana-Champaign Field Name : Topography of the Sea Floor Code : 14.01.00.B4236 Advisor: R.S. Harmon, ARO Detailed Proposal

Multi-scale characterization and simulation of near-shore environment using advanced GIS technology

1. Background and objective
Understanding near-shore processes is crucial for effective coastal management, especially with the increased population pressures, the threat of global warming and possible acceleration of coastline erosion problems. The general research strategy identified by the report "Near-shore Processes Research" (Thornton et al. 2000) focuses on combination of field experiments with numerical models spanning a range of scales. Both field measurements and models involve processing, analysis and visualization of large volumes of georeferenced data, often in different computational environments and formats. GIS would appear as a natural choice for integration of this type of data, however, because the studied processes are highly dynamic, and often distributed in 3 spatial dimensions, a traditional 2D static GIS is not sufficient (Raper 1999). Recent developments in integration of GIS and environmental modeling (Goodchild et al. 1996, GIS/EM4 2000, Mitasova et al. 1995) create an opportunity to extend the range of GIS applications to new areas such as oceanography and coastal studies. Emerging multidimensional GIS technology can substantially increase efficiency in data processing and provide the tools to gain new insights into geospatial aspects of complex coastal systems. It also creates new opportunities to improve coastal planning and management (NOAA 2000).

While there have been several examples of successful linkage between a GIS and coastal monitoring and modeling systems such as MIKE 21, MIKE INFO COAST (DHI 2000); HyPAS (USACE WES 2000), many problems remain to be solved. To fully support the use of GIS in coastal research and management, the GIS should have capabilities for:

Recent developments in OPEN Source GIS (Mitasova et al. 1995, Neteler 2000), as well as the industry-wide moves towards open, extendable GIS (ESRI 2000) have the potential to provide capabilities, and develop new, customized tools which can be easily linked with the general GIS. The advancements in coastal and marine GIS have been described in a monograph edited by Wright and Bartlett (1999) who conclude : "Linkages have been successfully made between GIS and a wide variety of process models drawn from the terrestrial domain: in the natural environment, these include groundwater contamination models, soil loss equations, surface hydrological models etc. In contrast, many of the techniques involved in coupling marine and coastal models to GIS are still poorly investigated or understood, and thus the benefits and synergy that can arise from bringing these different tools together are rarely seen".

The goal of the proposed research is to investigate the potential of emerging multidimensional GIS to bring a new level of effectiveness and understanding into near-shore environment characterization and modeling. The project will focus on the development and application of GIS methods for processing of near-shore measurements, support for numerical modeling of interactions between the terrestrial and coastal processes, and multidimensional dynamic visualization. Special attention will be given to the issues of scale and multiresolution representation of processes and phenomena within the highly complex coastal environment. The possibilities to use the coupled GIS and simulation modeling for studies of human impact on near-shore processes and for improvement of sustainable coastal management will be explored.

2. General methodology The research will focus on evaluation, enhancement and application of OPEN source GIS methods and tools in the following areas:

Multivariate interpolation. Spatial interpolation and surface modeling for near-shore studies pose several special challenges. The key issues include support for temporal data, large heterogeneous data sets, incorporation of anisotropy and break-lines (Raper 1999). To create dynamic volumetric models from data which are scattered in both 3D space and time quadvariate interpolation is necessary (Mitasova et al. 1995). While some of these capabilities are provided in specialized geostatistical packages, all of the necessary tools are not generally available in GIS. However, a multivariate interpolation method called Regularized Spline with Tension (RST, Mitasova et al. 1995) which can fulfill these requirements was implemented into OPEN source GIS in its bivariate form (Mitasova and Mitas 1993). It supports processing of large data sets by using quad-tree and oct-tree segmentation, incorporates anisotropic tension and processing of noisy data is enabled by spatially variable smoothing. The accuracy of the interpolated surface can be assessed using the estimates of predictive errors by a cross-validation procedure. Linkage of OPEN source GIS with the OPEN source R statistical package (Bivand and Neteler 2000) provides additional capabilities for statistical analysis of measured data and interpolated models.

The proposed project will focus on application of the bivariate RST method, implementation of additional capabilities necessary for near-shore research, and incorporation of the trivariate and potentially also the quadvariate version of the RST method within the GIS using the experiences with a prototype presented by Mitasova et al. (1995). One of the unique properties of the RST method are its regular derivatives in all points of the surface. This property has been used to compute gradients and curvatures of the surface simultaneously with interpolation (Mitasova and Hofierka 1993), which increases the consistency of surface analysis. RST method will be used to perform analysis of bathymetric and coastal terrain geometry at a hierarchy of scales and impact of surface geometry on near-shore processes such as sediment transport will be investigated. The new tools will be tested by applications to coastal measurements that were obtained through previous ARO supported research using swath bathymetry techology and rapid kinematic survey.

Modeling of near-shore processes. There has been a significant progress in physics-based distributed modeling of coastal processes represented, for example, by systems of engineering modules integrated e.g., in the MIKE 21 software (DHI 2000) or CEDAS (USACE WES 2000). Most of the near-shore process models are based on solutions of differential equations using finite difference and finite element methods. Besides these traditional methods, path sampling is emerging as one of the promising approaches for modeling of transport of suspended solids, such as sediment and pollutants (MIKE 21 PA: DHI 2000; Dimou and Adams 1993, Mitas and Mitasova 1998). The method is based on duality between the particle and field representation of spatially distributed phenomena. Within this concept, density of particles in space defines a field, and vice versa, a field is represented by particles with corresponding spatial distribution of their densities. Using this duality, processes can be modeled as evolution of fields or evolution of spatially distributed particles. The path sampling technique has several unique advantages. The method does not require special meshes, so the standard GIS grids can be directly used. Its formulation is multidimensional so it can be used for both 2D and 3D simulations (MIKE PA: DHI 2000) and it can be implemented as a multiscale tool using nested grid approach. The independence of sampling points makes this stochastic method perfectly suited to the new generation of computers as it provides scalability from a single workstation to large parallel and distributed computers.

Based on the experience with spatial modeling of surface hydrology and overland flow erosion, the possibilities of using the path sampling method for simulation of selected near-shore processes will be explored, with focus on capturing the impact of human induced changes and the interaction between the terrestrial and near-shore processes. The governing equations for these processes will be analyzed and general modules for path sampling simulations will be designed. The design will focus on providing the components which will allow to build models for a wide range of processes which could be implemented in OPEN source GIS. The possibility to directly link the simulations with observed data for potential online monitoring of pollution sources (Catin and Fortin 2000) will be explored using the principles proposed by DHI (2000) for MIKE PA 21.

Multidimensional dynamic visualization. Most of the current GIS coastal applications are restricted to 2D static or animated maps or 2D cross-sections of volumetric data due to the lack of support for 3D and 4D visualization in the most commonly used commercial systems (although there are systems which provide full support for such data e.g. Intergraph ERMA or specialized visualization systems such AVS, IBM Explorer, but their use for GIS applications has been limited). Based on the experiences with simultaneous visualization of multiple dynamic surfaces and volumes along with the standard GIS data within the OPEN source GIS (Mitasova et al. 1995, Brown et al. 1995), various approaches to visualization of multi-scale dynamic phenomena necessary for near-shore modeling will be explored and the most effective methodologies for analysis and communication of coastal data and results of simulations will be designed.

Study area. The research will be performed for a section of North Carolina Coast near Duck USACE WES Coastal Field Laboratory which was focus of the extensive ONR and ARO supported field experiments.

3. Expected results and their significance
The proposed research aims at bringing new ideas, techniques and approaches based on the use of the emerging multidimensional GIS technology to problems of coastal management and studies of near-shore processes. The focus on OPEN source GIS development and implementation will contribute to the rapidly growing open source geospatial computing infrastructure and benefit from modifications and enhancements by international team of GIS developers.





4.References:

Bivand R., Neteler M. (2000) Open Source geocomputation: using the R data analysis language integrated with GRASS GIS and PostgreSQL data base systems. Proc. 5th conf. on GeoComputation, Univ. of Greenwich, U.K

Brown, W.M., M. Astley, T. Baker, H. Mitasova (1995) GRASS as an integrated GIS and visualization environment for spatio-temporal modeling. Proc. Auto-Carto XII, ACSM/ASPRS, Charlotte, NC, 89-99.

Cantin J.F., Fortin P. (2000) Integration of Numerical Models and Field Characterization into a Georeferenced System for Oil Spill Emergency Response , Proc. 4th conf. on GIS and Env. modeling, CDROM, Banff, Canada.

Dimou, K.N., Adams, E.E. (1993) A random particle tracking model for well-mixed estuaries and coastal waters. Estuarine, Coastal and Shelf Science, Vol 33, pp. 99-110.

Danish Hydrologic Institute (2000) DHI software. www.dhi.dk

ESRI (2000) www.esri.com

GIS/EM4 (2000) Proceedings of the 4th conference on GIS and Environmental modeling, CDROM, Banff, Canada http://lithophyte.ngdc.noaa.gov/cgi-bin/subview3.cgi

Goodchild, M.F., L. T. Steyaert, and B. O. Parks, eds. (1996) GIS and Environmental Modeling: Progress and Research Issues. Ft. Colins: GIS World, Inc.

Goodchild, M.F., L. T. Steyaert, and B. O. Parks, eds. (1997) GIS and Environmental modeling . Proceedings of the 3rd conference on GIS and Environmental modeling (Santa Fe), NCGIA, CDROM .

Intergraph (2000) ERMA. www.intergraph.com

Mitas, L., Mitasova, H., (1999) Spatial Interpolation. In: P.Longley, M.F. Goodchild, D.J. Maguire, D.W.Rhind (Eds.), Geographical Information Systems: Principles, Techniques, Management and Applications, Wiley, 481-492.

Mitas, L., Mitasova, H. (1998) Distributed soil erosion modeling for effective erosion prevention. Water Resources Research, 34, 505-516.

Mitas, L., Brown, W. M., Mitasova, H. (1997) Role of dynamic cartography in simulations of landscape processes based on multi-variate fields. Computers and Geosciences, 23, 437-446.

Mitasova, H., L. Mitas, B.M. Brown, D.P. Gerdes, I. Kosinovsky (1995) Modeling spatially and temporally distributed phenomena: New methods and tools for GRASS GIS. International Journal of GIS, 9 , 443-446.

Mitasova, H., L. Mitas (1993) Interpolation by regularized spline with tension : I. Theory and implementation. Mathematical Geology 25, p. 641-655.

Mitasova, H., J. Hofierka (1993) Interpolation by regularized spline with tension : II. Application to terrain modeling and surface geometry analysis. Mathematical Geology 25, p. 657-669.

Neteler, M. (2000). Advances in open source GIS software. Proceedings from the "1st National Geoinformatics Conference of Thailand, Bangkok.

NOAA (2000) Coastal visions 2025. www.noaa.gov

Raper, J. (1999) 2.5 and 3D GIS for coastal geomorphology. In: Wright D. and Bartlett, D., (Eds), Marine and Coastal Geographical Information Systems. Taylor & Francis, 129-136.

Thieler E.R., Pilkey O.H., Young R.S., (2000) The use of mathematical models to predict beach behavior for US coastal engineering: A critical review. J. of Coastal Research, Vol 16(1), 48-70.

Thornton E., Dlarymple T., Drake T., Elgar S., Gallagher E., Guza B., Hay A., Holman R., Kaihatu J., Lippmann T. and Ozkan-Haller T. (2000), State of nearshore proceses research II. Technical report NPS-OC-00-001, Naval Postgr. Schools, Monterey, California.

USACE WES (2000) CEDAS, HyPAS. www.usace.army.mil

Wright, D. and Bartlett, D., (Eds), (1999), Marine and Coastal Geographical Information Systems. Taylor & Francis.





Signature of Applicant________________________________________ Date _____________________


1 Signature of Applicant Date

2 Signature of Applicant Date

3 Siganture of Applicant Date