DPC Technology Watch Report Preserving Geospatial Data
Guy McGarva, Steve Morris, Greg Janée · 2009
Geospatial data are becoming an increasingly important component in decision making processes and planning efforts across a broad range of industries and information sectors.The amount and variety of data is rapidly increasing and, while much of this data is at risk of being lost or becoming unusable, there is a growing recognition of the importance of being able to access historical geospatial data, now and in the future, in order to be able to examine social, environmental and economic processes and changes that occur over time.The geospatial domain is characterized by a broad range of information types, including geographic information systems data, remote sensing imagery, threedimensional representations and other location-based information.The scope of this report is limited to two-dimensional geospatial data and data that would typically be considered comparable to paper maps or charts including vector data, raster data and spatial databases.There are a number of significant preservation issues that relate specifically to geospatial data, including: the complexity and variety of data formats and structures; the abundance of content that exists in proprietary formats; the need to maintain the technical and social contexts in which the data exists; and the growing importance of web services and dynamic (and ephemeral) data.Standards for geospatial metadata have been defined at both the national and international levels, yet metadata often becomes dissociated from the data, or is incorrect, non-standard in nature, or not created in the first place.Additional considerations to be taken into account in preserving geospatial data include coordinate reference systems, cartographic representations, topology, project files and data packaging.Standards bodies are in place at the national and international levels to address general geospatial data standardization issues, yet working groups addressing preservation issues have only recently been formed.A number of technologies and tools that are, or may be, of relevance to geospatial data preservation efforts have emerged, although the nature of the problem is such that there is not a single tool or technology that will be relevant in all cases.A number of projects and activities have been addressing various aspects of geospatial data preservation, creating an initial body of experience from which some initial recommendations can be made.While these recommendations provide a basic checklist of issues to be considered when preserving geospatial data, it must be emphasized that the collective experience in preserving such data is still very much in an early stage and that further investigations are needed.