? GeoSemantica GeoSemantica is an ontology based web services architecture designed for integrating, translating and sharing multivariant information and knowledge assets (geospatial and news media) in a distributed network environment. It is part of a much broader initiative within the Earth Science Sector of Natural Resources Canada to build a web-based architectural framework to situate and promote the use of integrated earth science information, knowledge and expertise within a broader societal context. Our work focuses on the research and development of integrated knowledge systems and semantic web applications that will facilitate the understanding and uptake of earth science information in support of interdisciplinary research, planning and decision-making on issues of public safety, resource management and sustainable development. Combining semantic web browsing with Internet GIS and knowledge discovery tools, GeoSemantica is intended to help broaden and deepen both an awareness and understanding of sustainability issues in the context of both collaborative learning and decision support. In addition to the technological component, we are also involved in developing earth science sub-models to help address issues of public safety and resource scarcity in the broader context of place-based sustainability planning. Hazard Modelling Software One product of MAP:GAC is a geological hazards modelling software package that will allow South American hazards experts to simulate hazard processes, create scenario maps, and enhance their ability to produce hazard maps. Such software is needed particularly where new hazard conditions arise or where there is insufficient geological knowledge of past events for a historically-based hazard assessment. Once complete, the software will be free and courses will be offered on its appropriate use. The software will consist of an open architecture whose visible component will be a graphical user interface with G.I.S. functionality. Various process models, whether they are phenomenological, numerical / process, or probabilistic in nature, will "plug-in" as modules to the software structure. Users will input required parameters, initial conditions and digital elevation models needed by the models, and the software will then produce scenario maps and possibly probabilistic hazard maps. In the short term (2003-2005) the modelled processes will include landslides, debris flows, ash fall and ash plumes, with potential later additions of earthquake shaking, pyroclastic flow and surge, and lava flow. The software will be developed through collaboration between the MAP:GAC project, professional associations and academic researchers involved in specific process model development. Hazardous process simulation is an active area of research and we intend to employ relatively standard / accepted / recommended models, or facilitate the development by scientists of research models. Our main task will be the coordination of the effort, supply of GIS and software design expertise, the design and translation of the software structure and graphical user interface, testing, training or coordination of training, and a context for the application of the product. We will provide some support to involved scientists to facilitate their contributions. This is an opportunity for researchers to focus on applying their science, without spending major effort to produce user-friendly software, advertise it, maintain it, or train people on it. The benefit to science is that cutting-edge models will see abundant application and testing. In addition to contributing to the development of process modules, we will involve scientists and where possible professional / scientific associations for guidance and the review and approval of models for use in the software, and the standardized presentation of the results as hazard maps. The software is planned to be inclusive rather than exclusive, so that there may be multiple models available for individual hazard processes, provided they meet criteria of functionality. The production of the first version of this software package is expected to happen over the next two years, with a following two years of testing, revision and application.