Modernly, Geospatial Technology has two main subdivisions and studies: Human and Physical. While all "Geospatial" mappings are based upon a map of a physical area, that area is then overlayed with data either of a physical nature or a human (man-made) nature. Below are examples of each:

• Physical Geographies & Studies:
  • Climatology
  • Geomorphology
  • Biogeography
  • Soil Geography
  • Natural Resource Management
  • Environmental Studies
• Human Geographies & Demographics:
  • Population
  • Economy
  • Culture
  • Politics
  • Health/Medicine
  • Education

Government Programs and Initiatives

• 1965-1968- NASA launches the GEOS (Geodynamics Experimental Ocean Satellite) 1 and 2, with the goal of creating a framework that connected all the Earth's major landmasses
• 1971- International Satellite Geodesy Experiment program begins, using GEOS 2 to further explore satellite mapping capabilities
• 1972- NASA launches first Earth Resource Technology Satellite (ERTS)
• 1994- President Clinton issues Executive Order 12906, titled “Coordinating Geographic Data Acquisition and Access”
• National Spatial Data Infrastructure (NSDI)- assists with the management of Geospatial data and promotes cooperation between the local, state, and national subdivisions of government

Mapping Data: Raster vs. Vector 

Data entered into a geographic information system is most often found in two distinct forms – discrete objects (i.e. a building) and continuous fields (i.e. elevation, rainfall). Likewise, both types of data are stored in two formats, each with their own advantages: raster and vector.

Data storage is best described in a visual sense. Raster data consists of an extended grid of cells where each cell is a different value. Each cell has the capability to represent a different variable, ranging anywhere from colors to create images to the ability to store continuous values in a long string of data. Because each cell is of equal proportion, the cells in the grid are viewed as a whole when a computer or person is attempting to analyze the data. Vector data, on the other hand, uses coordinate geometry to define various areas to store the data. Points and lines connected in a polygonal fashion distinguish different areas of data from each other.

With both types of data, additional information can be attached and stored easily. Raster data often possess a separate attribute table that corresponds with the raster grid, and vector values can have an identifier tag placed on them containing an additional description of the included data points.

Military Applications

As with commercial imagery, unmanned aerial vehicles (UAVs) are becoming increasingly important to both operational support and as a way to augment space-based technical means of collection. UAV platforms are transforming intelligence, surveillance and reconnaissance (ISR) concepts by providing persistent surveillance, precision engagement and dominant battlespace awareness to support our warfighters.

UAVs obviously have some limitations as well. Current systems do not have the immediate global reach that a satellite has; it takes time to move assets to a theater. They can suffer damage from bad weather or hostile ground fire. Current UAV systems do not provide the metadata in their data sets that could provide accurate target location for weapons that use geopositioning for guidance. Finally, UAVs are a cost efficient alternative for some missions, when compared to a space-based system. They are cheaper and faster to replace if a sensor or subsystem fails. UAVs also provide a cost efficient test platform for a sensor, improving its reliability before ultimately installing it on a space-based platform.

Additionally, a GIS can be used to store and display data needed as basemap data for the military applications showing contours, transportation routes and cities. GIS is used by the military to aid their understanding of regional terrain and how it affects overall battlefield support. Satellite imagery and GIS terrain data can give information about potential landing site analysis, vehicular travel time, field of view and line of site assessement. Hence it aids in the tactical decision. A GIS can display feature information stored as aerial photographs simultaneously. These data can create a more realistic rendition of the area while clarifying specific features needed for navigation. These digital map provides a commander in the field with state-of-the-art technology that can identify a position, interrogate that position for access to water, fuel, cover and parking for vehicles, determine areas of visibility to the enemy and assess its strength and develop strategies accordingly.

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