MIKE INFO Coast - An Extension for Coastal Zone Management

Background

With the spread of computer technology in the recent years, however, it has become apparent that the task of evaluating model result data is no longer solely the task of the model expert. An explicit need for user-friendly access to complex models and their results has been expressed. In order to accommodate this DHI has developed various interfaces to the models. As all the models of DHI ultimately express geographic information, a GIS (ArcView) has been chosen for the presentation of the model related data. Thus, several modules have been developed as add-ons to the DHI models. E.g. MIKE 11 GIS for MIKE 11, MOUSE GIS for MOUSE. Common to the above mentioned GI-modules are that they require a model to supply data.

 Inspired by the recent EAGLE-project where a GIS-based system was developed for presentation of many different kinds of data (such as hydrographical and biological data, model result data, images etc.) DHI has set out to create a suite of information systems for presentation and management of environmental data. This suite of products has been coined MIKE INFO, and it is the intention to develop MIKE INFO products for various areas of data management. One of these areas is the management of coastal data, and the corresponding product is MIKE INFO Coast.

What is MIKE INFO Coast?

• Data Management. All coastal data are stored and maintained within one system.
• Data Manipulation. The coastal data can be edited and modified.
• Data Presentation. The data can easily be presented in various ways.
• Report Generation. Reports can be generated and saved for later use.

In ArcView/MIKE INFO Coast the user interface depends on the current active document, i.e. the user interface changes as the active document changes. ArcView contains several types of documents, which all have their individual user interface. When loading the MIKE INFO Coast extension, you actually load a new type of document into ArcView. This type of document is called �coast�, and has its own tailor-made user interface especially suited to work with coastal zone data. For instance the user interface covers options such as �calculate differences between surveys�, �import sediment size data� and other functions specific to coastal zone data.

 A situation of typical use would be a coast, where bathymetric line surveys are performed regularly to record the depths. After each survey, the recordings will be imported into MIKE INFO Coast and processed. This processing involves organising the survey lines into so-called profiles. These profiles can then be compared from survey to survey, and differences (i.e. changes in the bathymetry) can then be calculated. The screen-dump below shows one such session, where a difference between two surveys has been calculated. Having processed and presented the bathymetric survey data within MIKE INFO Coast a report can be generated and saved for later.

 Fig 1. Difference calculation using MIKE INFO Coast.

MIKE INFO Coast has been used in-house in several projects (in countries such as the United Arab Emirates, Malaysia and Bangladesh). Typically, a stretch of more than 30 km shoreline are to be maintained. Data as diverse as hydrographical, biological data, images, maps and (of course) survey data has been covered in the projects. The MIKE 21 modelling system has also been applied in some of the cases, and input/output routines between the two products has been implemented. Having developed and tested MIKE INFO Coast for several years in-house, DHI has released the first version - 1.0 - in public (October 1997). In the hour of writing, an update enhancing the facilities of MIKE INFO Coast is planned. It is expected to be released medio 1998.

Data Handled by MIKE INFO Coast

• Maps. Obviously, as it is based on a GIS. The maps would typically cover coastlines, groynes, buildings etc. The maps can be stored in shapefile format, which is ArcView�s native format.
• Other geographically related data. This covers measurements of depths/heights (with geographic reference) and profiles. Also included is any data derived from the depth measurements, such as interpolated surfaces, results from difference calculation etc. Survey related data with a geographical reference are also stored as shapefiles.
• Administrative data. This covers data with no geographical reference (e.g. general survey information). These data are stored in dBASE IV-format, which is a well-known database format and immediately supported by ArcView. However, these data could also be stored in an external database and reached through ODBC.
• Regularly measured hydrographic data. This covers measurements at fixed positions of variables such as wind speed/direction, wave height etc. Hydrographic data are stored in ASCII-format which makes on-line data acquisition easier, should the need arise.
• Water quality data. This covers data such as BOD, Chlorophyll, Secchi Depth etc. Basically any water quality data (and hydrographical data) can be stored as it is possible for the user to specify which parameters are relevant in a given project.
• Sediment data. In the case were sediment samples have been collected and analysed it is possible to keep this information within MIKE INFO Coast as well.
• Background images. These images are related to the maps, and can be satellite photos and/or aerial images.
• Other images. This covers photographs taken at fixed ground locations in a certain direction. If several photo surveys have been performed it is possible to compare photographs from the same location but taken at different times.
• Model result data. This covers data to and from LITPACK and MIKE 21. Model data are imported/exported in the ASCII-format exported/imported from the relevant model.

Functionalities in MIKE INFO Coast

• Import of measured/surveyed point. These points are imported from a simple ASCII- file containing XYZ-format data.
• Editing of measured points. It is possible to edit the imported surveyed points in various ways. You can delete erroneous points, add new ones, shift the datum of all or some of the points etc.
• Organising the measured points in profiles. You can define a set of profiles in various ways (interactively by pointing, automatically generated or imported). Then you can organise your measured points relative to these profiles, by projecting the points onto the profiles.
• Calculation of differences between profiles. Having organised your measured points you can compare data from various surveys. Thus, you can calculate the difference between two profiles and get an estimate of the erosion/deposit for that particular profile.
• Generation of reports. The generated reports can always be edited using the built-in ArcView functions, so the user is not limited by the standard presentations and reports offered by MIKE INFO Coast.

The functions mentioned so far primarily concern data organised in profiles. However, MIKE INFO Coast does not require this kind of organisation. Other functions are listed below:
 

• Generation of contours. It is possible to generate a set of contours by interpolating the measured or projected point data.
• Difference calculation covering an area. You can calculate differences between two surveys by generating difference maps from interpolated maps.
• Editing and viewing hydrographical data. You can specify stations were hydrographical data are measured. A dedicated tool for managing the often very large time-series is supplied with MIKE INFO Coast.
• Image support. Viewing and report generation of background images and directional photos are supported.
• Handling of sediment sample data. Apart from storage and editing, various presentations of sediment sample data are included, such as a standard particle size distribution curve.
• Presentation of MIKE21/LITPACK data. MIKE INFO Coast contains very powerful presentation facilities, when it comes to 2D-modelling. Figure 2 shows a report presenting flooding (calculated using MIKE 21) viewed as a cross-section. (Note, this form of presentation also requires the Spatial Analyst extension, as the data are stored in GRID format.)

Fig 2. MIKE INFO Coast report presenting flooding in cross-section view. The example is from the Bay of Bengal, where flooding as a result of cyclones occur frequently.

Conclusion

References

Foster, T.M. and Skou, A.J., 1992. LITPACK, An Integrated Modelling System for Littoral Processes and Coastline Kinetics. 3rd International Software Exhibition for Environmental Science & Engineering. Como, Italy.

Skou, A., Hedegaard, I.B., Fredsøe, J. and Deigaard, R., 1991. Applications of Mathematical Models for Coastal Sediment Transport and Coastline Development. Proceedings of COPEDEC III. Mombasa Kenya.

Warren, I. R. and Bach, H. K., 1992. MIKE 21: A modelling system for estuaries, coastal waters and seas. Environmental Software 7. Elsevier Science Publishers Ltd.