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ESCI 4515/6515, PLAN 6515: Introduction to Geographic Information Science. Spring 2008 Instructional material prepared by Taff & Ozdenerol. Lesson 1: Intro to Geographic Information Science (GISc). Geography = Place names only?. World Population.
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ESCI 4515/6515, PLAN 6515:Introduction to Geographic Information Science Spring 2008 Instructional material prepared by Taff & Ozdenerol
Lesson 1: Intro to Geographic Information Science (GISc) Gregory Taff
Geography = Place names only? Gregory Taff
World Population The heavier the color, the more the population. Gregory Taff
Population Growth Rate The heavier the color, the higher the growth rate. Gregory Taff
World Vegetation Gregory Taff
GIS Provides the Framework for Studying Complex Systems Gregory Taff
GIS Facilitates Learning About Earth and Its Life Gregory Taff
Intro to Geographic Information • 1.1 The “G” in GIS (Geographic Information Systems) • Geography – Patterns and processes of human and physical phenomena on the surface of earth. • Examples of geographic information: • Location of Memphis • Interstate I-40’s spatial layout • Distribution of world population density • Urban sprawl/development throughout Tennessee over the past 100 years. • Water quality of Michigan Lake. • Water pipe lines in Shelby county. Gregory Taff
Geographic Information examples (cont.) • Static or dynamic • For the same object, for example, a car, its spatial position might change over time. • For the same location, like Memphis, you can study its population changes over time. • Census information changes between decades • Landcover maps change with development, new crops, etc. Gregory Taff
1-2 Variables in Geographic Information Geographic information involves: • Location/Spatial information of objects • Objects: • Points (air pollution monitoring station) • Lines (the location of the length of a road) • Polygons (the boundaries of a county) • Pixel (from a satellite image) • Location/spatial information – coordinate system • Latitude and longitude • UTM • State Plane • Attributes • Income levels of census tract • Air pollution levels at monitoring station • Elevation of a topographic contour line Gregory Taff
1-2 GIS Example – layers of data Gregory Taff
Overlay (of data layers) Gregory Taff
Change layers (here a 2002 satellite image) Gregory Taff
Sources of GIS data • There are many ways we can obtain GI data. Popular ways – • Surveying/Field work • Remote Sensing • Digitizing old maps • Purchasing • Get free data by downloading from Internet, copying from CDs borrowed from library. Gregory Taff
1-3 Formats of Geographic Information • Paper maps • Tabular data (weather station lists of city temperatures) • Text (a description of a place) • Digital format, necessary to copy/analyze using software. Gregory Taff
1-4 Geographic Information Systems What is GIS? GIS is built on the collective knowledge from geography, cartography, computer science, and mathematics. A GIS has many definitions depending on whom you ask. GIS as a Toolbox: GIS is a powerful set of tools for storing and retrieving at will, transforming and displaying spatial data from the real world for a particular set of purposes. Peter Burrough, 1986 This definition emphasizes a set of tools designed to solve specific problems. Gregory Taff
GIS definition GIS as an Information System: A geographic information system is a spatial case of information system where the database of observations reflects spatially distributed features, activities or events, which are definable in space as points, lines, or areas. A geographic information system manipulates data about these points, lines and areas to retrieve data for queries and analyses. Ken Dueker, 1979 [edited by Taff]. The information system definition implies that GIS collects data, sifts and sorts them, and selects and rebuilds them to find the right information to answer a question. Gregory Taff
GIS definition Dueker’s definition only applies to the vector model of the real world, which represents the real world on a map as point, line, and area features. In fact, there is another model of the world, the raster model of the world, to which the definition does not apply. My preferred definition is a hybrid of both: “GIS is an information system that allows for capture, storage, retrieval, analysis and display of spatial data.” Note that GIS is closely tied to the infrastructure that exists for creating spatial data – satellites, census protocols, weather stations, land survey techniques, and more. Gregory Taff
Components of a GIS • Computer hardware • Software • Spatial data • (this can include the infrastructure needed to create spatial data) • People needed to operate the GIS This is a good test question! Gregory Taff
Components of a GIS • Hardware • Digitizer • Scanner • PC • Software • ESRI • Google Earth • Data • Remote sensing data • Census data and their geographically referenced coordinates • People • GIS specialists • GIS analysts/technicians • Researchers • General public (esp. with Google Earth and personal GPS receiver devices Gregory Taff
1-5 GIS Application classification GIS users - applications • Government • Census bureau • Dept of Agriculture • Dept of Defense/CIA • Dept of Transportation • Education & Research • Land use change research • Environmental monitoring • Seismological research • Population research Gregory Taff
1-5 GIS Application classification (Cont.) • Business • Real estate development • Ski resort planning • Trucking company – inventory and route planning • Personal • Yahoo maps, Google Earth • GPS and map tracking system in automobiles • Palm pilot Zagat’s guide, etc. Gregory Taff
1-5 GIS Application classification (Cont.) GIS applications, considered by functionality • Information Management – data input, data editing and updating. • Data output and display • Maps • Spatial information queries • Time series of maps (Weatherman shows movement of cloud cover over the region) Gregory Taff
1-5 GIS Application classification (Cont.) • Spatial Analysis – • Shortest Distance • Overlay • Buffer analysis • Classification • Spatial modeling – has all above features. • Simulations (weather) for understanding and prediction • Real-time Systems (Forest fire, military, etc., using real time data.), Gregory Taff
1-6 The Role of GIS within Geograhpy • GIS is an effective tool that integrates human and physical geography • GIS can combine (and overlay) human and physical data • E.g., envr mgt, hazards… • Tool v.s. science • GIS is a tool for those who use it to conduct research on other subjects • GIS is also a science, as is computer science. GISci v.s. GIS. Gregory Taff
1-7 Synonymous Terms for GIS • Geographic Information Systems (US) • Geographical Information Systems (Europe) • Geomatics (Canada & Europe) • GeoInformatics (Europe & Asia) • Spatial Information Systems • Geographic Information Science Gregory Taff
The Market • In 2003 the US Dept of Labor listed these as the three fastest growing emerging career fields in the US (order not specified): • Biotechnologies • Nanotechnologies • GIS Gregory Taff
GIS Market Share - 2000 Data from GIS Monitor Gregory Taff
GIS Market Share-2001 Gregory Taff
Geographic information systems – cont. • GIS internet resources: • Try googling “GIS”, you will find a lot of GIS related websites. Some examples: • USGS (Geological Survey)’s brochure Geographic Information Systems (http://www.usgs.gov/research/gis/title.html) • News services – www.gismonitor.com, www.spatialnews.com, www.giscafe.com, www.geoplace.com. Gregory Taff