Geographic Information Systems: Putting it all together

The thing about GIS

Some examples of GIS online Maricopa County Assessors’ Office Interactive Maps Yavapai County Interactive GIS USGS – Various web mapping applications related to environmental studies and management

What GIS is NOT: Maps A software system It is not GPS (Global Positioning System) Often these are components of an effective use of a geographic information system.

What is a Geographic Information System (GIS)? National Science Foundation: A computer-based system for capture, storage, retrieval, analysis and display of spatial (locationally defined) data

Definition 1: a tool box for data capture Alabama4,461,130 Alaska628,933 Arizona5,140,683 State Apportionment Population digitize scan convert format manual entry graphical nongraphical

Definition 2: an information system for data management Storage Retrieval updates Querying: Retrieving a particular subset of data

riverfactory With the type of flood that occurs on an average once in a hundred years, what area would flood? If there was a chemical explosion, how far would the toxic chemicals spread? Definition 3: manipulation & analysis

Definition 4: an approach to science “The generic issues that surround the use of GIS technology, impede its successful implementation, or emerge from an understanding of its potential capabilities” (Goodchild, 1992) GIScience is research both on and with GIS GISystems changed the entire approach to spatial data analysis Technology has become simpler and easier to use GISystems and GIScience has crossed disciplinary boundaries

GISystems, GIScience and GIStudies GISystems Emphasis on technology and tools GIScience Fundamental issues raised by the use of GIS and related technologies (e.g.) Spatial analysis Map projections Accuracy Scientific visualization GIStudies Systematic study of the use of geographic information GIServices

100 year flood zone area affected by chemical explosion Definition 5: a display

Definition 6: a multi-billion dollar business “The growth of GIS has been a marketing phenomenon of amazing breadth and depth and will remain so for many years to come. Clearly, GIS will integrate its way into our everyday life to such an extent that it will soon be impossible to imagine how we functioned before” (Clarke)

August 2004, Geospatial technology is listed by the US Department of Labor as one of the three most important emerging fields. GIS industry is worth over $7 billion Software Data Services Publishing Education …a multi-billion dollar business

What is Geospatial Technology? Computer Cartography

Data Entry: Enter 2218 locations into spreadsheet Data Processing: Add spatial data to spreadsheet: full addresses or latitude and longitude coordinates Data Analysis: Classification, range grade data, overlay analysis, create visual variables

Cartography by Conrad Brewjo Every detailed map = hours of work

Global Positioning Systems What is Geospatial Technology?

Remote Sensing What is Geospatial Technology?

30m, LANDSAT

1m, IKONOS

place.com/gw/ 2002/0201/020 1wtc.asp place.com/hott opics/groundze ro/default.asp

GoogleEarth!

…a multi-billion dollar business Critical to the growth of the industry 1. Federal Government Data 2. Successful advocate of itself at all levels and internally 3. GUI software and automation 4. Merged with parallel technologies to become “geospatial technology industry”

Definition 7: a societal role GIS as “organized activity by which people measure and represent geographic phenomena, and then transform these representations into other forms while interacting with social structures” (Chrisman 1999)

Organized collection of Hardware Software Data People Procedures Networks People Software Data Procedures Hardware Societal Role…

Moral and ethical implications Favors generalization Not always neutral Technological rather than human-need focused Maintains and extends societal power structures Societal Role…

Functional definition of GIS: A system for dealing with space-time data, that has the following functions: Data input Data management Data manipulation and analysis Data reporting

Example: a new bus route $$$ for bus service improvements How could GIS be used to help determine the best location for a new bus route?

Where can we get relevant data? Population density Potential ridership Existing bus routes Distance willing to walk Environmental impact? US Census bureau, topographic maps, town records, aerial photographs Marketing questionnaire, demographics Valley Metro Marketing questionnaire Air quality measurements, estimates of pollution in microclimates

Key GIS elements Organize each type of information into its own data layer

Key GIS elements Set up data so it overlays correctly

More key elements: Analysis Create a buffer of ¼ mile around existing bus routes To learn more, take advantage of links between locations and attributes

GIS links location and attributes links Location files: store info about boundaries, locations, adjacency Attribute files: store info on non- spatial characteristics of the features

In summary … GIS allows for spatial data acquisition, storage, manipulation, and analysis Output can be many different forms!