Here is an essay on ‘Geographic Information System (GIS)’ for class 8, 9, 10, 11 and 12. Find paragraphs, long and short essays on ‘Geographic Information System (GIS)’ especially written for school and college students.
Essay on GIS
Essay Contents:
- Essay on the Introduction to Geographic Information System
- Essay on GIS History
- Essay on GIS Components
- Essay on Geographic Spatial Object-Concept
- Essay on GIS as a System and Decision Support Tool
- Essay on GIS as a Tool
- Essay on Core Groups of GIS Activities
- Essay on Requisite Resources for GIS
- Essay on the Selection of GIS Software
- Essay on GIS Benefits
Essay # 1. Introduction to Geographic Information System:
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The geographic information relates to the specific location. It involves physical environment with the data associated. The GIS is an organized collection of computer hardware designed system to create, manipulate, analyze and display all types of geographically or spatially referenced database, efficiently.
The GIS also allows complex spatial operations, which are very difficult to perform. The geographic concern data is related to the geographic scales of measurement. The geographic data are referenced by the coordinate system in respect to the location on the earth surface.
Few important points about GIS are outlined as under:
i. GIS is the data handling and analysis system. The data should be spatially distributed in two-dimensions.
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ii. It is a geo-based or geocoded information system.
iii. It is an information system, in which the data is geographically referenced.
iv. GIS is a means of creating and editing the list of different setups to display their records in the form of tables, graphics or maps.
v. GIS stores, retrieves, manipulate, analyze and displays the data as per user- defined specifications.
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vi. GIS is a decision support system involving the integration of spatially referenced data.
There have been proposed many definitions of GIS, but they conform to a particular task.
In actual sense, what GIS does, are outlined as under:
i. Measurement of natural and artificial phenomenon based data, and process them in spatial perspective. The measurement emphasizes three types of properties, i.e., the elements, attributes and relationships.
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ii. Storage of measured informations in digital form in computer database. The data are linked to the features on digital map. The features may be in three types, namely the points, lines and areas (polygons).
iii. Analysis of collected data to generate other requisite data; and to derive new relationships with them, and also develop models with the generated data.
iv. Depiction of measured or analyzed data in the forms of display maps, graphs, lists, or summary statistics.
Essay # 2. GIS History:
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The GIS is due to advent of computer system. The application of computer-based group of softwares for storage, analysis and display of geographic data is the Geographic Information System. The first computerized GIS was introduced as a project under Rehabilitation and Development Agency Program in Canada, in the year 1964.
This information system was named as the Canada Geographic Information System (CGIS). The main task of CGIS was to analyze the land inventory of Canada to provide a kind of aid in land development for agriculture point of view. The CGIS software is still in use.
From the mid-1960s to 1970s the developments in GIS were mainly by the government agencies and by the universities. The Harvard Lab for Computer Graphics was established to promote GIS technology. The Harvard Lab developed several GISs in which SYMAP (Synagraphic Mapping System), CALFORM, SYMVU, GRID, POLYVRT and ODYSSEY are the main. The ODYSSEY was the first modern vector GIS; its features form a kind of basis for commercial applications.
In the late 1960s the Automatic Mapping System was introduced by the Central Intelligence Agency (CIA), United States, America; and based on which the CAM software was developed to create maps at different scales. From 1980s to 1990s, many GIS applications have been made, worldwide. And simultaneously several packages/softwares have also been developed/refined for better use or friendly use. At now, the most common softwares of GIS are the Arc Info, Arc View, Map Info, SPANS GIS, PAMAP GIS, INTERGRAPH, and SMALL WORLD.
Essay # 3. GIS Components:
The major components of GIS are outlined below:
1. Input System:
Its function is to collect the requisite data.
2. Computer Hardware and Software Systems:
Its main functions are as under:
i. To store the data.
ii. To allow for data management.
iii. To allow for data analysis; and
iv. To display the data manipulation on computer monitor.
3. Output System:
Function of this component is to generate hard copy of maps, images and other types of outputs.
In GIS basically two types of data are used; they are:
i. The data on real world phenomena and features having few types of spatial dimension. These data are depicted mathematically in the form of points, lines or polygons, which are referenced geographically in coordinate system. For feeding this type of data, the devices such as scanners, digitizers, GPS, air photos and satellite imagery are used.
ii. The data called attributes, are in pieces, which are in the forms of points, lines or polygons and map. Such types of data are entered directly in the computer database, where they are linked with the element data.
The user can enter, analyze and manipulate the associated data to some spatial elements in the real world, within GIS database. The cartographic GIS software displays the geographic information at any scale, projection and also in variety of the layers.
In which each layer expresses different aspects regarding the points/place taken into consideration on the earth. In addition, the layers also indicate the view, how they are seen. The things may be the road network, topography, vegetative cover, streams and water bodies, or distribution of rainfall in the region.
Essay # 4. Geographic Spatial Object-Concept
:
It includes graphics, illustrating the informations about the area under consideration.
Mainly, the following two types of data provides a kind of basis for GIS:
i. Vector layers; and
ii. Raster data.
The vector layers include the lines, points and polygons. It is coordinate based data structure for representing the map features. Each object is presented in the form of list of sequential x-y coordinates indicating the attributes of object. The polygon includes the boundaries of the area.
The associated terms are outlined as under:
i. Point:
On map a particular object represents specific locational information. The map object is defined by x.y coordinate. Objects are indicated by a specific symbol such as circle, square, triangle etc., on the map.
ii. Line:
It is the line joining two specific points on the map. Line is also considered as map object. It is defined by a set of sequential coordinates representing the generalized shape of geographic features such as street centres, railroads etc.
iii. Polygon Area:
It is the area feature. It is defined by a series of enclosing segments and nodes.
iv. Triger Files:
The TRIGER (Topologically Integrated Geographic Encoding and Referencing System) files are the best data layers for GIS applications in emergency management.
The raster data or image is a graphic presentation of an object that is typically produced by an optical or electronic device. The image may be the satellite images, scanned pictures and photographs. The photos or satellite images are the raster image. It is a kind of computerized picture consisting of rows of tiny dots called pixels.
The raster images area is called bitmaps. The image data can be arranged in a number of ways depending on the format of particular image. Normally, the image data file contains a header record for storage of the informations about image such as number of rows and columns in the image, the number of bits per pixel, the colour requirements and geo-referencing informations.
Essay # 5. GIS as a System and Decision Support Tool:
GIS as a System:
The GIS involves following basic elements to use spatial data:
i. Input – It includes encoding, collection of phone listing and census information by geographic area- block groups or tracks.
ii. Data Management – It is storage, retrieval and analysis of data using different softwares such as Arc View, Map Info, Geo Media, Land View/Marplot etc.
iii. Output – The output is the map showing risk zones, vulnerable population and phone listing in vulnerable areas.
GIS plays very important role in decision-making. Several modifications have been made in GIS to identify its role in decision- making. The decision support is an excellent goal for GIS, however the level of decision ranges from major (foreign aid project to support with limited budget) to minor. Although, the GIS is best tool for decision support, but not for differentiating their applications; because individual GIS systems are being suitable for different types of decisions.
Essay # 6. GIS as a Tool
:
GIS is useful for spatial analysis and geocoding. In spatial analysis, an operation that examines the data with the intention to extract or create new data to satisfy few required condition or conditions, is carried out. It includes GIS functions as polygon overlay or buffer generation and the concepts of contents, intersects within or adjacent.
In geocoding the management of large database of events is done by putting address such as customer records, tax records etc. Normally, the addresses are the common form of storing geographic data. Geocoding facilitate to display the tabular informations in computerized database with address as points in the map; and also to find their locations on the map. Addresses also specify the location in the same way as the geographic coordinates. The data source can be used to compute and assign the coordinates if the data source features have addresses.
In general, the geocoding allows for following functions:
i. Development of map to show location of different events by addresses.
ii. For query and finding geographic features using addresses.
iii. For performing point-in-polygon analysis such as finding all the customers in a given trade zone.
iv. To analyze crime by their addresses, and to locate their position on the map. And also to analyze other demographic data.
v. To identify the potential impacts of any treatment etc.
Essay # 7. Core Groups of GIS Activities
:
GIS is coalescence of groups of users, managers, academicians and professionals working with the spatial informations. Each group has a distinct features such as educational background, societies, magazines and journals, conferences, traditions etc. Because of this reason each group identifies itself with particular ways, approaching particular set of problems. The interactions between groups are made through joint memberships, joint conferences and organizations. These groups further have another basis for characterizing their application areas.
The core groups of GIS activities are summarized below:
1. The technologies, which Interact with GIS, Sharing its Technology and Creating Data for it:
Under this core group the following activities are the main:
i. Surveying and engineering
ii. Cartography; and
iii. Remote sensing.
2. Management and Decision-Making Groups:
Under this the followings are considered:
i. Preparation of resource inventory and management.
iii. Preparation of land records for taxation and ownership control.
iv. Facilitating management
v. Marketing and retail planning; and
vi. Vehicle routing and scheduling
3. Science and research activities at universities and government labs.
Essay # 8. Requisite Resources for GIS
:
For GIS the followings are mainly considered as the important resources:
1. Computer hardware
2. Computer software
3. Geographic data
4. Procedures, and
5. Trained staff.
Computer Hardware:
Under this, a computer with all accessories is required to perform all the works related to GIS. The computer must be of fast speed with at least 1500 Mb RAM along with large monitor (at least 17 inch size).
In addition, the following items are also required under computer hardware:
i. A colour printer of 17 x 14 inches printing.
ii. A plotter for preparing 36-inch wide maps.
iii. A scanner for scanning photographs or maps.
Computer Software:
There have been developed several computer softwares on GIS. They are easily available in the market. Few are available at website, free of cost. The Geo Media, Arc View and Map Info are the reasonable priced powerful GIS softwares. The other GIS softwares are listed in Table 28.7 and 28.8.
Geographic Data:
The databases that have well clarity and can be geocoded or geographic coordinates are mainly counted under GIS database. Also, the census bureau, water features, image data such a photos, satellite images or USG Squad sheets can be the data for GIS applications.
For developing GIS layers the followings are essential to take into considerations:
i. The source for each data layer.
ii. Owner of the data layer and the method by which the new GIS layer is to be integrated.
iii. Responsible source for data updating.
iv. Cost of data allocation.
v. Availability of accessed data for the general public; how and by whom.
vi. Responsible sources for achieving and retention of the data layer.
The GIS layering involves following steps:
i. Data storage
ii. Analysis of data
iii. Preparation of maps
iv. Storage of files, and
v. Sharing of files.
The operator of GIS computer software must be well acquainted with the software, and should also have full knowledge of computer handling. Also, he should have the knowledge on the computer programming.
Training Staff and Technical Support:
For efficient and effective operation of GIS the associated staff must have a good training on the subject. It should be on priority; otherwise, the work may not be so accurate. If the concerned person has not a good exposure on the subject, then he must be allowed for getting advance training. However, the training must also be essential for each individual involved in the project.
Staffing Requirements:
There are few essential requirements for the technical staffs to be employed for handling the tasks under GIS project, such as:
i. GIS technical staff must have knowledge on file management, database formatting and computer aided graphics. These knowledge for GIS staff is very essential to have a better understating about the project.
ii. The staff should also have a good exposure on computer operation, including printing, scanning, server filing etc.
iii. The technical staff must be capable to perform data layering.
iv. They should also have full ability to test the work done, whether the done work is as per requirement of organization or not.
Essay # 9. Selection of GIS Software:
The GIS software selection depends on the required information about products, data requirements and the functionality requirements, mainly. Based on the following points, one can arrive at best possible selection of GIS software to satisfy the requirements –
i. Successfulness of the software.
ii. Software standards – It should be as per IT standards.
iii. Adequate supports from the supplier.
iv. GIS platform that provides all the capabilities necessary to support the vision, i.e.
(a) Geographic database to store and manage all geographic objects.
(b) A Web-based network for distributed geographic information management and sharing.
(c) Desktop and server applications for data compilation, information query, spatial analysis, geo-processing, cartographic production, image visualization and GIS data management.
(d) Modular software components (engines) to embed GIS logic in other applications and custom applications.
(e) Geographic information services for multi-tier and centralized GIS systems.
Essay # 10. GIS Benefits:
Various benefits of GIS are outlined as under:
i. It provides informations to accelerate decision-making associated to the emergency planning, response, recovery and mitigation efforts.
ii. Provides maps of the concern, and of the areas of special interest for emergency management.
iii. Conducts spatial quires and displays the results.
iv. It also make possible for complex spatial analysis such as the area, residents and business that is vulnerable from a chemical release, from a fixed facility or an intersection.