What your students need to know: Core Concepts in GIS

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What your students need to know Core Concepts
in GIS

• Dr. David R. Bowne
• Center for Teaching, Learning, and Technology
• dbowne_at_richmond.edu
• ACS-GIS Symposium, Feb. 28 March 2, 2003

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Sample Topics in GIS courses

1. What is a GIS?
2. Map projections coordinate systems
3. Types of geographic data
4. Getting data from the web
5. Digitizing/creating new coverage
6. GPS
7. Geoprocessing
8. Spatial Queries
9. Joining Tables
10. Network Analysis
11. Geodatabase
12. Remote Sensing
13. Raster Analysis

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Objective

• Explore GIS concepts that all users, no matter
  how casual, should know.
• Are a subset of previous list.

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1) Conceptual Domain of GIS

• What a GIS is and is not.
• Mapping and so much more.
• Relationships between GIS, GPS, and Remote
  Sensing

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2) Types of Geographic Data

• Vector
• Polygon Polyline
• Point
• .

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Types of Geographic Data

• Raster
• Collection of cells or pixels, each with a
  specific value

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3) Data Formats

• Spatial and Attribute Data
• Layers, coverages, shapefiles

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4) Coordinate Systems

• Geographic
• Uses a 3D spherical surface to define locations.
• Longitude and latitude, often expressed as
  decimal degrees.
• Not uniform units of measure

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Coordinate Systems

• Projected
• Mathematical transformation of 3D earth to 2D map
• Causes distortion in either shape, area,
  distance, or direction

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Buffer shape dependent on projection
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5) Map Scale

• Mathematical representation of size on map versus
  size in reality
• 124,000 means 1 unit on map 24,000 units on
  earth
• Small scale (11,000,000) represents a large area
  
• Large scale (110,000) represents a small area

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Improper Analysis because of Scale
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6) Metadata

• Data describing data
• When was the layer created, for what purpose, by
  whom, when relevant, what accuracy?
• Explanation of codes, abbreviations
• Coordinate System and Projection

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GIS Curriculum Sources
Each are developing core curriculum

• http//www.ucgis.org/index.htm
• http//www.ncgia.ucsb.edu