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The term Digital Earth Reference Model was coined by Tim Foresman in context with a vision for an all encompassing geospatial platform as an abstract for information flow in support of Al Gore's vision for a Digital Earth. The Digital Earth reference model seeks to facilitate and promote the use of georeferenced information from multiple sources over the Internet. A digital Earth reference model defines a fixed global reference frame for the Earth using four principles of a digital system, namely:
The distinction between "digital" versus "analog" Earth reference model is made in the manner the entire Earth surface is covered. Tessellation refer to a finite number of objects/cells that cover the surface as discrete partitions while Lattice refer to ordered sets of points that cover the surface in continuous vector space. The mathematical frame for a digital Earth reference model is a tessellation while the mathematical frame for an analog Earth reference is a lattice.
The value of a digital Earth reference model to encode information about the Earth is akin to the value obtained from other digital technologies, namely synchronization of the physical domain with the information domain, such as in digital audio and digital photography. Efficiencies are found in data storage, processing, integration, discovery, transmission, visualization, aggregation, and analytical, fusion and modeling transforms. Data reference to a Digital Earth Reference Model becomes ubiquitous facilitating distributed spatial queries such as “What is here?” and “What has changed?”. Image and signal processing theory can be utilized to operate on data referenced to a DERM.
The DERM structure is data independent allowing for the general quantization of all georeferenced data sources onto the common grid. Application, algorithms and operations can then be developed on the grid independent of data sources.