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Introduction to GIS. Longley et al. (2001), GISystems and Science , Ch 1. Data – numbers, text, symbols Sea surface temperature, soil type, population density Information – differentiated from data implying some degree of selection, organization, and preparation for particular purpose, or
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Introduction to GIS Longley et al. (2001), GISystems and Science, Ch 1
Data – numbers, text, symbols Sea surface temperature, soil type, population density Information – differentiated from data implying some degree of selection, organization, and preparation for particular purpose, or data given some degree of interpretation Geographic Information (map, digital form) Information about places on Earth’s surface Geographic versus spatial Geographic refers to Earth’s surface and near surface Spatial refers to any space (more general) Knowledge about where something is Knowledge about what is at a given location Can be very detailed or very course Can be relatively static or change rapidly Can be very sparse or voluminous Opening Definitions
Information Systems • Help us to manage what we know • Make it easy to organize and store, access and retrieve, manipulate and synthesize, and apply solution of problems • Examples of Information Systems
Geographic Information Technologies • Technologies for collecting and dealing with geographic information • Global Positioning System (GPS) • Remote Sensing • Geographic Information System (GIS)
What is GIS? GIS stands for “Geographic Information Systems” • Special kind of “information system” • Uses special information about what is where on the Earth’s surface
What does a GIS look like?How would I know one if I saw one? Two distinct meanings of the question “Is this a GIS?” • GIS is a real application including hardware, data, software and people needed to solve a problem (a GIS application) • GIS is a type of software sold by a software developer GIS hardware like any other computer with perhaps some extra components. Like? What is important is the kind of information that’s stored. In addition, a GIS includes tools to do things with this information. • Special functions that work on geographic information
Spatial is Special • Almost all human activities and decisions involve a geographic component • Technical reasons why geographic information is special[Longley et al. (2001) Box 1.2] • Multidimensional (at least 2 coordinates to define a location) • Voluminous • Often must be projected onto flat surface • Requires special methods of analysis
GIS Software Vendors ESRI – http://www.esri.com Intergraph – http://www.intergraph.com Autodesk – http://www.autodesk.com Clark Labs – http://www.clarklabs.org
What is GIS used for? Why go to all this trouble and expense? Who needs to know what is where? Few of the most important uses: • Utility companies • Transportation • Farmers • Planning • Forestry
Why Does GIS Matter? “Almost everything that happens, happens somewhere. Knowing where something happens is critically important.” Longley et al. (2001, 6) Because location is so important, it is an issue in many of the problems society much solve
Geographic problems Problems that involve an aspect of location • Information used to solve the problem • Solutions themselves Classifying geographic problems • Spatial scale • Intent or purpose • Temporal scale Examples • Location of a new highway • Management of forests • Precision agriculture
Systems, Science, StudiesWhat does it mean to be “doing GIS”? What’s the “S” in GIS • Using the tools and helping to build the tools of geographic information systems (GISystems) • Studying the theory and concepts that lie behind GIS and other geographic information technologies (GIScience) • Study the societal context of geographic information – legal context, issues of privacy, economics of geographic information (GIStudies) Wright, Dawn J., Michael F. Goodchild, and James D. Proctor. 1997. GIS: Tool or Science? Annuals of the Association of American Geographers, 87(2): 346-362.
Geographic Information Science Term coined in a paper by Goodchild (1992) Goodchild, Michael F. 1992. Geographic Information Science. International Journal of Geographical Information Systems, 6:31-45. Studies the fundamental issues arising from geographic information; body of knowledge that GISystems implement and exploit Address questions: • How does a GIS user know that the results obtained are accurate? • What principles might help a GIS user to design better maps? • How can user interfaces be made readily understandable by novice users? Other terms meaning same as GIScience Evolved significantly over the past 10 years • Research journal renamed • UCGIS – http://www.ucgis.org In 1996, UCGIS institutions held an assembly to identify the most important research topics • International Conference on GIScience - http://www.giscience.org
Scholarly Journals Emphasizing GIS Research • International Journal of GIScience (formerly International Journal of GISystems)* • Cartography and GIScience (formerly American Cartographer and Cartography and GISystems) • Computers and Geosciences* • Computers, Environment and Urban Systems • Photogrammetric Engineering and Remote Sensing* • Transactions in GISystems • Geographical and Environmental Modeling • Geographical Analysis* • GeoInformatica* • Annals of the Association of American Geographers* • Journal of Geographical Systems* (successor to Geographical Systems) *UD subscribes
Big Questions in GIScience UCGIS> Priorities > Research > 2002 Research Agenda • dedicated to promotion of GIScience
Disciplines of GIScience Traditionally researched • geographic information technologies • digital technology and information • studied Earth • worked to integrate knowledge from different disciplines within context of Earth’s surface • studied nature of human understanding and its interactions with machines