Fundamentals of spatial data warehousing for geographic knowledge discovery
Similar to many research and application fields, geography has moved from a data-poor and computation-poor to a data-rich and computation-rich environment. The scope, coverage and volume of digital geographic datasets are growing rapidly. Public and private sector agencies are creating, processing and disseminating digital data on land use, socio-economic variables and infrastructure at very detailed levels of geographic resolution. New high spatial and spectral resolution remote sensing systems and other monitoring devices are gathering vast amounts of geo-referenced digital imagery, video and sound. Geographic data collection devices linked to global positioning system receivers allow field researchers to collect unprecedented amounts of data. Position aware devices such as cell phones, in-vehicle navigation systems and wireless Internet clients allow tracking of individual movement behaviour in space and time. Information infrastructure initiatives such as the US National Spatial Data Infrastructure are facilitating data sharing and interoperability. Digital geographic data repositories on the World Wide Web are growing rapidly in both number and scope. The amount of data that geographic information systems can handle will continue to increase exponentially through the mid-twenty-first century.