Geog 206
1a)
GIS Definition one from: http://www.webopedia.com/TERM/G/GIS.html
Short for Geographic Information Systems, tools used to gather, transform, manipulate, analyze, and produce information related to the surface of the Earth. This data may exist as maps, 3D virtual models, tables, and/or lists.
GISs can be as complex as whole systems that use dedicated databases and workstations hooked up to a network, or as simple as "off-the-shelf" desktop software.
GISs play an important role in many organizations. For instance, police and fire departments may use GISs to locate landmarks and hazards, plot destinations, and design emergency routes. GISs may also be used by governments, research institutes or any other body that can't possibly handle the task of manually processing large amounts of geographical data.
GIS Definition two from: http://gps.about.com/od/glossary/g/GIS.htm
A Geographic Information System, or GIS, integrates data, hardware, software and GPS to assist in the analysis and display of geographically referenced information.
GIS is a general term that refers to any scientific effort to integrate data to help researchers visualize, analyze, and explore geographically referenced information. For example, GIS is helping researchers measure the speed of glacier melting in Greenland and Antarctica. GIS can assist in the analysis of small-scale and localized data, as well, such as development trends, or watershed analysis.
The field of GIS has advanced rapidly in recent years, with the availability of rapidly increasing computer power, development of software, and proliferation of inexpensive GPS devices.
GIS is frequently used to create maps that illustrate hidden data. For examples, visit Geodata.gov.
GIS Definition three from: http://www.nwgis.com/gisdefn.htm
GIS (Geographic Information Systems) is a system of hardware and software used for storage, retrieval, mapping, and analysis of geographic data. Practitioners also regard the total GIS as including the operating personnel and the data that go into the system. Spatial features are stored in a coordinate system (latitude/longitude, state plane, UTM, etc.), which references a particular place on the earth. Descriptive attributes in tabular form are associated with spatial features. Spatial data and associated attributes in the same coordinate system can then be layered together for mapping and analysis. GIS can be used for scientific investigations, resource management, and development planning.
GIS differs from CAD and other graphical computer applications in that all spatial data is geographically referenced to a map projection in an earth coordinate system. For the most part, spatial data can be "re-projected" from one coordinate system into another, thus data from various sources can be brought together into a common database and integrated using GIS software. Boundaries of spatial features should "register" or align properly when re-projected into the same coordinate system. Another property of a GIS database is that it has "topology," which defines the spatial relationships between features. The fundamental components of spatial data in a GIS are points, lines (arcs), and polygons. When topological relationships exist, you can perform analyses, such as modeling the flow through connecting lines in a network, combining adjacent polygons that have similar characteristics, and overlaying geographic features.
1b)
All definitions discuss GIS somehow as a computer-based system to support the gathering, preservation, storage, retrieval, analysis, output, and distribution of spatial data and information.
1c)
The main difference lies in the amount of information’s provided. Where some definitions are right to the point, others are giving detailed information’s about GIS as an information system as well as an approach to science. However, some definitions contain further unique phrases and descriptions.
1d)
As a result, one can consider the field of GIS as one with many different aspects that can be used in many different areas of life.
2.)
Example one from: http://libraries.mit.edu/gis/examples/examples.html
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| City Space |
Overall, the map demonstrates the Boston Metro Area. The color red illustrates industrial land; the pink coloring refers to “Other” that is currently used land and the grey area shows all other values. The map serves as verification that land that was used to be utilized by industrial development is in fact empty space today and hence can be used for redevelopment projects. Therefore, there is in fact space to live or build in the city of Boston, much of it is even close to business district and connected to transportation.
Example two from: http://libraries.mit.edu/gis/examples/examples.html
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| Pure Water Access |
Example three from: http://libraries.mit.edu/gis/examples/examples.html
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| Sea Surface Temperatures |
3.)
Differences between maps (Cartography) and GIS:
• In general, output from GIS does not have to be a map.
• Text output may be more important than a map for analysis reporting.
• Many GIS are designed with poor map output capabilities.
• The main differences between a GIS and a mapping system are in their functional components.
A GIS contains these four components: a. Input b. Database c. Analysis d. Output
In contrast, a mapping system can be described in three components: a. Input b. Map design c. Output
Similarities between maps (Cartography) and GIS:
• Much GIS output is in the form of hard copy maps or graphic displays.
• Design of graphic output is critical to effective use of GIS analysis.
• Maps are the main source of data for GIS and GIS has roots in the analysis of information on maps.
• Many standard GIS operations were conceived and executed where possible on analogue maps.
• Many people use GIS to make maps.
• Both cartography and GIS however use map/data layers.
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