Overview What is geography? What is geographic information? What is a GIS? GIS applications Tool versus science

Geography = Place names only?

What is geography? The scientific study of the locational and spatial variation in physical and human phenomena Where things are located on the earth’s surface How places differ from one another How people interact with the environment

Geographic Information Examining patterns & processes of human and physical phenomena on the surface of earth Examples of geographic information: Spatial distribution of world population totals or growth rates Location of Chapel Hill Interstate I40’s spatial pattern Urban sprawl/development of Raleigh over time

Geographic Information (GI) GI - static or dynamic? Static: Does not change position Locations, such as city/town, lake, park Dynamic Car with On-Star recording its position Studying population change at a particular location over time Motorola, Nokia,

What is GIS? Many definitions, depending on whom you ask A computer-based system to aid in the collection, maintenance, storage, analysis, output, and distribution of spatial data and information

Components of a GIS Computer hardware Software Spatial data Data management and analysis procedures Spatial data People needed to operate the GIS

Computer Hardware Computers Disk storage Digitizers and scanners Printer and plotter output devices

Components of a GIS: software ArcGIS from the Environmental Systems Research Institute (ESRI) ERDAS Imagine from Earth Resources Data Analysis System

Components of a GIS: Spatial Data Aerial photographs Digital remote sensing Surveying Global Positioning System Digitizing maps Censuses

Data in GIS (vector model) Pasture So you have your Entities, your real world objects that you want to put into the GIS. Entities are represented by Data Objects. A data object is… House Road

Data in GIS (raster model)

Reasons for GIS applications? GIS address environmental problems. Identify the source, location, and extent of the adverse environmental impacts. Many businesses need GIS Where are the potential customers? What is the spatial distribution of competing businesses? Public organizations need GIS Monitor urban growth and use GIS for rational planning Emergency service vehicles are dispatched and routed using GIS

GIS Application Areas Government Business Education & Research Census Bureau: population Dept of Agriculture: soils data Dept of Defense/CIA: monitoring Dept of Transportation: roads data Political redistricting Business Researching retail markets Evaluating site suitability Evaluating health care resources Education & Research Land use change research Environmental monitoring Seismological research Population research