What is a GIS?
- Geographic: Geography is the scientific study of the locational and spatial variation in both physical and biological phenomena on Earth. (The "where")
- Information: A collection of facts or data. (The "what")
- System: A group of interrelated parts working together (hardware, software, data, people...).
Formal definition of GIS: "A computer-based system to aid in the collection, maintenance, storage, analysis, output and distribution of spatial data and information (Bolstad, 2008)"
- Spatial data is data with a "spatial component" describing where something is located on the Earth.
- Aspatial data:
Elements of GIS
- Collection: Internet, web services, GPS...
- Maintenance: Quality control, metadata...
- Storage: Files, folders, databases...
- Analysis: Too many to list!
- Output: Maps, tables, reports, pubs...
- Distribution: Websites, web services...
Modeling the Real World
A world of physical entities that occupy space: (plants, trees, rivers, streets, etc.)
- What: What are the physical features of interest and what are their properties and attributes?
- Where: Where are these physical features located, both in terms of their absolute location (i.e., their coordinates) and their locations relative to other physical entities (their topology)?
- When: When are certain conditions true and how do things change over time?
Get Answers to Questions
- What exists at a certain location?
- Where are certain conditions satisfied?
- What has changed in a place over time?
- What spatial patterns exist?
- How close are things to one another?
- What if this condition occurred at this place?
Questions from Managers
- When and where should we:
- Spray for weeds?
- Build roads?
- Patrol for poachers?
- Protect habitat?
- Reintroduce species?
- Harvest?
- Monitor?
- Allow off-roading?
Test Your Knowledge
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