Web-based GIS technologies dedicated for presenting semi-dynamic geospatial data

Web-based geographic information systems related research and its applications have been making rapid progress. Computers with fast processing units and large amounts of memory allow for practical applications of time consuming and resource intensive algorithms, both for spatial analysis as well as visualization of large-volume data such as high resolution raster images, DTM and vector data. However, most Web-based geographic information systems are used for presentation of static data, while the area of dynamic and semi-dynamic data visualization has been mostly neglected. Novel applications of known devices and models such as synthetic aperture radar and oil spill simulations require interactive data presentation, which up until now has been mostly realized using standalone applications or thick Web clients. This paper describes a number of Web-based GIS technologies for presentation of semi-dynamic geographic information retrieved from many different sources. It also describes the possibilities these technologies provide for publishing interactive geospatial data such as oil spill spread animation overlaid on background data (eg. terrain elevation data, satellite imagery) and presented in a geographic context. Web-GIS technologies like ESRI ArcIMS (Arc Internet map server) and open source geoserver with OpenLayers client library were compared during the research. The paper presents their corresponding capabilities, interactive geographic information presentation efficiency as well as general performance when serving considerable amounts of data.