What is a GIS?

Geospatial technologies are technolo-gies for collecting and dealing with geographic information. There are three main types:

Global Positioning SystemsRemote SensingGeographic Information Systems

One of a Set

Defining GIS

• Different definitions of a GIS have evolved in different areas and disciplines

• All GIS definitions recognize that spatial data are unique because they are linked to maps

• A GIS at least consists of a database, map information, and a computer-based link between them

One Definition: A GIS is an information system

"An information system that is designed to work with data referenced by spatial or geographic coordinates. In other words, a GIS is both a database system with specific capabilities for spatially-referenced data, as well as a set of operations for working with the data" (Star and Estes, 1990, p. 2).

Paul Bolstad’s Definition

“a computer-based system to aid in the collection, maintenance, storage, analysis, output, and distribution of spatial data and information”

A Current World Definition:GIS is 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”

We usually understand GIS to be computer-facilitated system

GIS is NOT only software/hardware

Also includes:• Trained personnel• Supporting Institution• Protocols for use

Why Learn GIS?..... Because GIS is Everywhere

Why GIS in a Natural ResourcesCurriculum?

• Resource depletion/degradation

• Climate change• Urban-Rural interface

impacts on resources• General increase in

problem complexity• Public’s demand for

better information• Improved capabilities

Why computerize manual methods? 

• To bring together data from multiple sources (synthesis)

• Analytical power• measure distance, density, area• overlay and buffer• adjacency and proximity• vicinity (neighborhood)• networks

• Flexibility

• Output Quality

• Expanded capabilities - do the heretofore impossible

• Improved efficiency - reduce speed of analysis 10-fold or more

Historical Setting and GIS Evolution

Spatial Database Management links computer mapping with database capabilities (80s)

Computer Mapping automates the cartographic process (70s)

Multimedia Mapping full integration of GIS, Internet and visualization technologies (00s)

Manual Mapping for 8,000 years

Map Analysis representation of relationships within and among mapped data (90s)

The US Department of Labor identifies Geotechnology as one of the “three most important emerging

and evolving fields” of the 21st century (along with Biotechnology and Nanotechnology)

Visualizing Spatial Relationships

What spatial relationships do you SEE?

…do relatively high levels of P often occur with high levels of K and N?…how often?…where?

Phosphorous (P)

Multivariate Analysis

The Precision Ag Process (Fertility example)

As a combine moves through a field it 1) uses GPS to check its location then 2) checks the yield at that location to 3) create a continuous map of the yield variation every few feet. This map is 4) combined with soil, terrain and other maps to derive 5) a “Prescription Map” that is used to 6) adjust fertilization levels every few feet in the field (variable rate application).

Farm dBStep 4)

On-the-Fly Yield Map

Steps 1) – 3)

Prescription Map

Step 5)

Zone 1

Zone 3

Zone 2

Variable RateApplication

Step 6)

Cyber-Farmer, Circa 1992

3-D Visualization ApproachesImage Draping -- is an established technique in GIS. Draping a topographic or thematic map onto a 3-D terrain surface is effective but relies on abstract colors, shading and symbols.

SportsTracker (MapTrek, 9/98)

“Map Abstraction”

Visualizing Landscape Impacts (GIS Rendering)

(Berry)

Visualizing Landscape Impacts (Clear cut)

(Berry)

Visualizing Landscape Impacts (Water retention cut)

(Berry)

When (time) Where (X,Y)

GPS Unit

Digital Camera

What (picture) When (time)

Geospatial Multimedia …take pictures with a digital camera or video recorder while carrying a GPS with ‘track logging’ then link the Lat/Lon with each picture.

Export to HTML and post to Internet

Pictures are “posted and linked” to a map

Google Earth (Killer App of 2005)

Vessel for Mapped Data— has brought Geotechnology to the masses; not a GIS but digests map data for 3D display with satellite imagery of the globe as backdrop

Geo-taggedPhotos

…and/or import GIS data layers into Google Earth(Wildfire Risk)

Philosopher’s Progression of Understanding—

Data (all facts)

Information (facts within a context)

Knowledge (interrelationships among relevant facts)

Wisdom (actionable knowledge)

GIS Utility and Understanding

…GeoExploration emphasizes tools for data access and visualization (general user)

…GeoScience emphasizes tools for spatial reasoning and understanding of geographic patterns and relationships (application specialist)

Mapping focus

Data/Structure and Analysis focus