Geographic Information Systems: Putting it all together

The thing about GIS

Some examples of GIS online

Maricopa County Assessors’ Office Interactive Maps

http://www.maricopa.gov/assessor/gis/map.html

Yavapai County Interactive GIS http://mapserver.co.yavapai.az.us/Interactive/map.asp

USGS – Various web mapping applications related to environmental studies and management

http://rockys20.cr.usgs.gov/RMMC/Main/hud.html

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

Alabama 4,461,130 Alaska 628,933 Arizona 5,140,683

StateApportionment

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

river factory

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 yearflood zone

area affectedby 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 spreadsheetData Processing: Add spatial data to spreadsheet: full addresses or latitude and longitude coordinatesData 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

http://www.geoplace.com/gw/2002/0201/0201wtc.asp

http://www.geoplace.com/hottopics/groundzero/default.asp

http://visibleearth.nasa.gov/cgi-bin/viewrecord?7846

GoogleEarth! http://earth.google.com

…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

PeopleSoftware

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

linkslinks

Location files:store info about boundaries,locations, adjacency

Attribute files:store info on non-spatial characteristicsof the features

In summary …

GIS allows for spatial data acquisition, storage, manipulation, and analysis

Output can be many different forms!