Understanding Geospatial Technology
Geospatial technology is defined as “an information technology field of practice that acquires, manages, interprets, integrates displays, analyzes or otherwise uses data focusing on the geographic, temporal and spatial context.” Organizations throughout the world use geospatial technology to transform previously hand-produced maps into high quality applications that can be beneficial to gas and electric utilities, government agencies, emergency vehicles, car manufacturers, private businesses and others. According to the Geospatial Information and Technology Association, approximately seventy to eighty percent of the information managed by a business is connected to a specific location or point, whether it is an address, street, intersection or coordinate. Geospatial technology is critical to the effectiveness of emergency response programs. When equipped with the appropriate technology, response teams can more accurately and speedily locate those in need. Local municipalities rely on this technology to route emergency vehicles, redraw voter districts, establish tax valuations, route sanitation vehicles, replace water mains and match the right equipment to the job. Farmers rely on geospatial technology to track agricultural conditions and drought tendencies. The technology is used in the planning of utility distribution networks; it helps monitor pollution and assists in determining effective alternative traffic patterns.
Geospatial technology and spatial science bring together multidisciplinary fields of scientific study through the application of three distinct technologies: Geographic Information Systems (GIS), Global Positioning Systems (GPS), and Remote Sensing.
Geographic Information System, (GIS) – A geographic information system (GIS) is a system designed to capture, store, manipulate, analyze, manage and present all types of geographical data. The acronym GIS is sometimes used for “geographical information science” or “geospatial information studies” to refer to the academic discipline or career of working with geographic information systems. It is a large domain within the broader academic discipline of Geoinformatics. In its simplest terms, GIS is the merging of cartography, statistical analysis and computer science technology. The term GIS describes any information system that integrates, stores, edits, analyzes, shares and displays geographic information for informing decision-making. GIS applications are tools that allow users to create interactive queries (user-created searches), analyze spatial information, edit data in maps and present the result of all these operations. The three major components of a GIS are input, computer hardware and software and output subsystems.
Remote Sensing (RS) – Remote sensing can be defined as the collection of data about an object from a distance. Humans and many other types of animals accomplish this task with the aid of their eyes or by their sense of smell or hearing. Geographers use the technique of remote sensing to monitor or measure phenomena found in the Earth's lithosphere, biosphere, hydrosphere and atmosphere. Remote sensing of the environment by geographers is usually done with the help of mechanical devices known as remote sensors. These gadgets have a greatly improved ability to receive and record information about an object without any physical contact. Often these sensors are positioned away from the object of interest by using helicopters, planes and satellites. Most sensing devices record information about an object by measuring an object's transmission of electromagnetic energy from reflecting and radiating surfaces.
Within the context of geospatial technology, remote sensing generally refers to the use of aerial sensor technologies to detect and classify objects on Earth (both on the surface and in the atmosphere and oceans) by means of propagated signals (e.g. electromagnetic radiation emitted from aircraft or satellites). Remote sensing imagery has many applications in mapping land-use and cover, agriculture, soils mapping, forestry, city planning, archaeological investigations, military observation and geomorphological surveying, among other uses. For example, foresters use aerial photographs for preparing forest cover maps, locating possible access roads and measuring quantities of trees harvested. Specialized photography using color infrared film has also been used to detect disease and insect damage in forest trees.
The Global Positioning System (GPS) – GPS is a satellite-based navigation system made up of a network of 24 satellites placed into orbit by the U.S. Department of Defense. GPS was originally intended for military applications, but in the 1980s, the government made the system available for civilian use. GPS works in any weather condition, anywhere in the world, 24 hours a day. There are no subscription fees or setup charges to use GPS. GPS satellites circle the earth twice a day in a very precise orbit and transmit signal information to earth. GPS receivers take this information and use triangulation to calculate the user's exact location. Essentially, the GPS receiver compares the time a signal was transmitted by a satellite with the time it was received. The time difference tells the GPS receiver how far away the satellite is. Now, with distance measurements from a few more satellites, the receiver can determine the user's position and display it on the unit's electronic map.
A GPS receiver must be locked on to the signal of at least three satellites to calculate a 2D position (latitude and longitude) and track movement. With four or more satellites in view, the receiver can determine the user's 3D position (latitude, longitude and altitude). Once the user's position has been determined, the GPS unit can calculate other information, such as speed, bearing, track, trip distance, distance to destination, sunrise and sunset time and more.