GEOSPATIAL INFORMATION TECHNOLOGY (GIT)

GEOSPATIAL INFORMATION TECHNOLOGY

                Information Technology

Information, as used here, refers to a data element of some kind which is useful for a particular application such as decision making process. Even though information and data technically have been used interchangeably throughout the text, there is a slight distinction between the two words. The word “data” is one of those English derivations from Latin. It is the plural past principle of the Latin verb “dare” meaning “to give “ it is a plural word. Literarily translated, it means “given things”. The less used singular form is “datum”, meaning a given things. “Data” sometimes implies what is fed into the computer-number, alphanumeric words or letters. On the other hand, information is knowledge about something. If we are able to relate data to a particular text, then such data become information. For example, the digits 4849.872 and 7642.945 are data of some sort, if we happen to know that they represent the coordinates (X, Y) of a triangulation or traverse station, then they become information. This explains why the two words are, sometimes, used interchangeably in the text.

                Bangemann (1994) observes that throughout the world, information and communication technologies are generating a new industrial revolution already as significant and far-reaching as those in the past. This revolution has added new capacities to human intelligence and consequently, changed the way we work and the way we live together. Technological developments in computer systems and new demands have prompted the institutionalization of information technology (IT). It refers to combination of computer, communication and process technologies. It is an information infrastructure complex which concerns itself with communications, information acquisition and retrieval through on-line computer searches, word processing, data logging and storage, E-mail, internet communication, etc.

GEOSPATIAL INFORMATION

                Spatial information can be defined as data set describing an entity within a space. Space, on the other hand, is the continuous boundless expanse extending in all directions within which all things exist. When spatial data is referred to the earth, it is called geospatial or geographic information. Thus geospatial information can be defined as information that describes entities in space with reference to the earth. Such entities include natural, infrastructural and cultural (man made) features.

                We can distinguish the following types of space, namely, two-dimensional space, three-dimensional space and four-dimensional space. An object can be located in two-dimensional space in terms of Cartesian coordinates using two reference axes (X,Y) or in terms of geographical coordinate (Φ,λ), where Φ (phi) is the latitude and λ (Lambda) is the longitude. This pair of values uniquely locates any entity on the earth’s surface. In three-dimensional space, an object can be located in terms of Cartesian coordinates using three reference axes (X,Y,Z) or in terms of geographical coordinates (Φ,λ,h), where h is the height of the point above a given datum or reference ellipsoid. In a four-dimensional space, an object can be located by choosing three reference axes with time being the fourth axis in dimension. Hence, the location of an object in space-time system can be given as (X, Y, Z, t), where t is time. Time may refer to some observable epochs, say, the time distance from an astronomical phenomenon such as the passage of a particular star over the observer’s meridian. In a simple language, therefore, spatial information refers to data about location, shape and relationships among geographic features. Spatial information can be referenced to two, three or four-dimensional space.

                Geospatial Information technology is the science of design and management of spatial information systems. It is a computerized tool which supports activities involving the creation, storage, manipulation and communication of geoinformation together with their applications. This technology is a technical innovation because it came into practice only in the 80’s. Since then, interest in it has grown tremendously. GIT aims at optimal use of spatial information in planning, policy development, land and infrastructure management, etc. modern development and user needs have necessitated the application of spatial information (SI) analysis in a problem-solving sense because SI provides solution which could not be provided by the use of conventional products such as maps, plans and charts. Information technology can be applied in such areas as conservation and management, environmental protection, etc.