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Welcome to GEOG 070 Intro to Geographic Information. Autumn Session - 2005 Instructor: Gregory Taff. Lesson 1: Intro to Geographic Information. Geography = Place names only?. World Population . The heavier the color, the more the population. Population Growth Rate .
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Welcome to GEOG 070Intro to Geographic Information Autumn Session - 2005 Instructor: Gregory Taff
Lesson 1: Intro to Geographic Information 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
Intro to Geographic Information • 1.1 The “G” in GI (Geographic Information) • Geography – Patterns and processes of human and physical phenomena on the surface of earth. • Examples of geographic information: • Location of Chapel Hill • Interstate I40’s spatial pattern • Distribution of world population density • Urban sprawl/development of Raleigh over 100 years. Gregory Taff
GI examples (cont.) • Water quality of Michigan Lake. • Water pipe lines in Orange county. • GI could be static, or dynamic, depending on how you collect and study GI. • For the same object, for example, a car, its spatial position might change over time. • For the same location, like chapel hill, you can study its population changes over time. Gregory Taff
1-2 Variables in GI 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
Variables in GI • GIS data can contain Z-values (elevation) – e.g. for an airplane • Time – GI data usually will have a time stamp. • Updates of census information in a census tract • Land cover change of a plot of land (field may grow into forest). Gregory Taff
Sources of GI • 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 GI • GI exists in many formats • 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 as defined by Heywood • Computer hardware • Software • Data management and analysis procedures (this could be considered part of the software) • Spatial data • People needed to operate the GIS This is a good test question! Gregory Taff
Components of a GIS Software Commercial software – Esri family, ArcGIS, Arcview, etc. Hardware: Digitizer, scanner, PC, ETC. People GIS specialists, analysts, researchers, technicians, Operators, etc. Data: Shape files, Coverage files, Remote Sensing data, Census data, etc. Gregory Taff
1-5 GIS Application classification First, we can divide applications by customers • 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 (Happy Valley) planning • Trucking company – inventory and route planning • Personal • Yahoo maps • GPS and map tracking system in automobiles • Palm pilot Zagat’s guide, etc. • Entertainment (check out GoogleEarth) 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 (Greg Fishel 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 • 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): • GIS • Biotechnologies • Nanotechnologies • Data from GIS Monitor: 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: • Network newsgroup GIS-L (comp.infosystems.gis) • 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