Threats to the natural world, such as global warming and loss of biodiversity, as well as disruptions to human society from social conflicts and resource shortages make the need for better information for decisions pressing. Changing prevailing perceptions of the relationship between the human and natural worlds fosters a greater appreciation of the consequences of decisions and policies.
The volume of geospatial data is growing exponentially, but more data by itself is not the solution. Though this has been dubbed the "Information Age," a more accurate assessment of the current situation is that an abundance of data often obscures the information it contains. Better methods for collecting, processing, organizing, analyzing, and disseminating data make possible the creation of better information. GIS provides the framework and tools for producing information that leads to greater knowledge and awareness of the world, increases the efficiency of processes, and promotes sustainability.
Geospatial imagery has always contributed to the creation of geospatial knowledge and GIS. Much of the data used for mapping and GIS is built on this imagery. It has long been used as a background for vector data in utilities, public safety, and other GIS applications. While it is to be used for these purposes, the greater availability of imagery that is both more current and at a higher resolution has led to the use of imagery for change detection, the verification of vector data, geospatial analysis, and three-dimensional modeling.
As it has expanded from the single user to multiuser implementations across organizations and in federated systems, GIS has moved to additional platformsthe server, Web, and mobile devices. ArcGIS 9.3 Desktop, ArcGIS Server 9.3, ArcGIS Online, and ArcGIS Mobile combine to optimize the use of imagery for the generation of geospatial knowledge through GIS.