Coverage Data

Coverage Data

A coverage is the digital representation of some spatio-temporal phenomenon. Coverages play an important role in geographic information systems, geospatial content and services, GIS data processing, and data sharing.

A coverage is a special kind of geographic feature, with the distinguishing characteristics that other features have one particular value associated (such as a road number, which remains constant over all the road's extent) whereas a coverage typically conveys different values at different locations.

A coverage is represented by its "domain" (the universe of extent) and a number of range of values representing the coverage's value at each defined location. For example, a satellite image derived from remote sensing might record varying degrees of light pollution. Aerial photography, land cover data, and digital elevation models all provide coverage data. Generally, a coverage can be multi-dimensional, such as 1-D sensor timeseries, 2-D satellite images, 3-D x/y/t image timeseries or x/y/z geo tomograms, or 4-D x/y/z/t climate and ocean data. Actually, climate data sometimes occur as 5-D coverages, showing that the coverage goes beyond spatio-temporal axes.

An interoperable service definition for navigating, accessing, processing, and aggregation of coverages is provided by the Open Geospatial Consortium (OGC) Web Coverage Service (WCS).