Spatial Data and GIS

Spatial Data refers to information related to a location anywhere on the earth's surface, and allows users to look at an area or geographic feature in relation to other areas (in relation to changes over time and in relation to various factors).  Spatial Data describes both the location of a geographic feature and its attributes (non-locational information about a feature), usually stored as coordinates and topology. A feature's attributes may be viewed as descriptive information that is used to classify and/or describe a particular feature.

Spatial Data exists in many forms including digital maps and printed maps, aerial photography and digital satellite images and can be manipulated in desktop mapping or GiS programs such as ArcView, Mapinfo, or Intergraph. Common data formats include vector, raster and tabular:

  • Vector Data represents geographic features as points, lines, and polygons. Each point feature is represented as a single coordinate pair, while line and polygon features are represented as ordered lists of vertices. Attributes are associated with each vector feature, as opposed to a raster data model, which associates attributes with grid cells.  Examples of common vector formats are arc/info Export (.E00 files), Mapinfo MiD/MiF files, DXF and Shape (.shp).
  • Raster Data defines space as an array of equally sized cells arranged in rows and columns, and composed of single or multiple bands.  Each cell contains an attribute value and location coordinates.  Unlike a vector structure, which stores coordinates explicitly, raster coordinates are contained in the ordering of the matrix.  Groups of cells that share the same value represent the same type of geographic feature.  Examples of raster formats are TIFF, GIF, JPEG, and BMP.
  • Tabular Data is descriptive information, usually alphanumeric, that is stored in rows and columns in a database and can be linked to spatial data.

Spatial - Both the location of a geographic feature and its attributes. Spatial data includes digital maps, aerial photography and digital satellite images and can be manipulated in desktop mapping or GIS programs.

Statistical - Includes library, general and government statistical databases.

Software -  Required when viewing or working with data accessed via SANDS.

(GIS) Geographic Information Systems is an integrated collection of computer software and data used to view and manage information about geographic places, analyze spatial relationships, and model spatial processes.  GIS provides a framework for gathering and organizing spatial data and related information so that it can be displayed and analyzed. GIS is used as an analytical tool in academic and professional applications ranging from historical analysis of human settlement patterns to predictive modeling of environmental phenomena.

GIS assistance is not available.