Geography - GIS Systems
Geographic information systems called GIS in short, is a constituent of all the complex geographic information technologies that exist today. The Global Positioning System or GPS and remote sensing are all parts of the emerging technologies that are today referred to as GIS systems. GIS thus encompasses both the digital and geographical techniques involved in the systems used for the processing and dissemination of geographic information. (New Horizons for the Social Sciences Geographic Information Systems) GIS may be defined as an automated system that allows the creation, editing, studying, analyzing and displaying spatially referenced data. A GIS has the capacity to manipulate several different spatial datasets at the same time. GIS plays a significant role in resource planning and other planned activities with reference to the geographical aspects of an activity. (Definitions)
GIS makes use of both the traditional disciplines as well as technology. It is a technology that makes use of a wide variety of disciplines and as such may be considered an enabling technology. Geography is a traditional discipline and is the science of comprehending the world and man's place on it and is a constituent of GIS. Geography has made use of spatial analysis for a very long time and this has often been done in the manual form that forms the starting blocks of spatial research and analysis. Cartography is the display of spatial information and is another constituent of GIS. Cartography happens to be the predominant source of data for input to GIS either digitized or scanned. Designing and creating maps forms a significant component in what is the output function of GIS, which gives rise to the popular myth that production of maps is the function of GIS. (What is a GIS and What Does It Do?)
Traditional cartography is now changing to digitalized and automated modes and so terms like digital cartography and automated cartography...
Remote sensing is the collecting of images from space and aircraft as input data for GIS. The commercial satellite systems that are in place as well as those that are planned to be put in place will make remote sensing data more freely available. Remote sensing is gradually becoming the most important source of input data for GIS. Remote sensing offers a very distinct advantage in that it has a very low cost in proportion to the area covered. The newer satellites will be in a position to update information in almost real time basis giving more meaning to the input data. The analyzed and interpreted data is capable of being integrated in the GIS as can the original image. (What is a GIS and What Does It Do?)
Photogrammetry is the activity, wherein photographs taken from the air or space are utilized to create very precise maps of the land surface. Photogrammetry is another discipline of the GIS. Photogrammetry is capable of drawing maps with very precise positions of features in a coordinate system. Photogrammetry caters for high accuracy positional control for the Global Positioning System. Statistics is another discipline of GIS and several of the GIS models are statistically based. Spatial statistics is a significant component for the proper understanding of the distribution of phenomena on the surface of the Earth.
The next discipline of GIS is Computer Science. Computer Aided Design or CAD equips GIS with tools for improved means for data input, display and visualization. Developments in the field of computer graphics have enabled the provision of hardware and software capable of display of spatial information and an example of this is the advances in computer display size and the resolution. Database Management Systems or DBMS play a role in the design of systems and allows for handling vast amounts of data. Another discipline of GIS is Artificial Intelligence and Neural Networks. This discipline is…
