Lecture 1 - What is GIS? Flashcards
What is GIS?
Geographic information systems: a method that utilizes special software to analyze spatial data
What is the history of GIS?
- 1854: John Snow tracked cholera outbreak in London
- 1962: Roger Tomlinson created first GIS system in Canada for forestry and rural development (CGIS)
- 1964: Howard Fisher, grandfather of GIS, at Harvard
- 1980s: ESRI (ArcGIS)
What is geographic info?
- info about places on earth
- knowledge about what is where
What are geographic info technologies? give examples.
Computer tools to analyze spatial data; geomatics
ex.
- GPS: uses satellites
- GIS: uses spatial info as layers
- RS (remote sensing): sensing something without being in direct contact, commonly on satellites and planes
What is Tan’s favourite definition of GIS (component-based)?
GIS is a collection of computer hardware, software, geographic data, methods, and personnel designed to efficiently capture, store, update, manipulate, analyze and display all form of geographically referenced info
What are the 3 possible “S” that can follow GI?
- systems: tech for spatial info management (what and where)
- science: comprehending underlying conceptual issues (how of development)
- studies: understanding social, legal, and ethical issues associated with GIS application
What makes a GIS unique/special? (Why use it?)
- uses spatially referenced data (known location in specific coordinate system)
- graphical and attribute data input and editing
- selective and spatial attribute query
- specialized spatial analysis tools (ex. overlay, buffer zones, terrain analysis, etc.)
- map and report generation
Why can a GIS perform spatial operations?
- because it links diff data sets together using geography/space as a common key between data sets
- integrates spatial and other kinds of info within a single system
- offers consistent framework for analyzing geo data
How is map data separated?
Into layers/themes/overlays of discrete info
ex. hydrologic data on separate overlay from soil data
What are the two forms that a GIS can store data? What is the big difference between them?
Vector: uses points/nodes and connecting segments (lines) as basic building blocks for representing geo features (polygons)
Raster: data structured based on grid cells (pixels) to represent features
What kind of questions can a GIS answer?
- location: what is at …?
- condition: where is at …?
- trends: what has changed since …?
- patterns: what spatial patterns exist?
- modelling: what if …?
What types of queries are there? What are the difference between them?
Aspatial: does not require a map - ex. what is the avg pop of …?
Spatial: uses maps and lat/long to determine - ex. which cities are within 1000km of each other?
What was the first GIS map?
- Lascaux, France cave drawings (~35,000 yrs ago) to track animals
What was the first GIS analysis?
- Cholera map: a dot at each case and tracked it back to the water pump
What is the history of GIS overlays?
- hand drawn overlays were originally used to combine the info on separate maps of the same area
- used several transparent maps physically overlaid to trace and put together
What is an example of current GIS overlay uses?
- GPS collar transmitter/receiver to track migration in caribou and polar bears
- helps design wildlife protection programs
What are contributing disciplines to GIS?
- cartography: science of map making
- RS: science of earth observation from space
- geodesy: science of accurate earth measurements
- surveying: science of accurate measurement of natural and manmade features on earth
- photogrammetry: science of measurement from images
- image processes: science of handling and analysis of image data
What is the history of GIS development in Canada?
- Canada Land Info Systems: one of earliest GIS developed (1960s) and used to inform land management plans
- Harvard Lab for Comp Graphics/Spatial Analysis: software widely distributed and built base for GIS
- Census Bureau: used geocoded censuses and stimulated street network database development
- commercial GIS (ESRI)
What are the major areas of practical application of GIS?
- Mature technologies (ex. surveying/engineering, cartography, RS)
- Management and decision-making (ex. natural resource management, planning, marketing, vehicle routing, etc.)
- Science and research activities in universities and governments
Give natural resource management examples of GIS
- EIA
- toxic waste siting
- environmental remediation
- forestry management
- habitat analysis
Give land info systems (LIS) examples
- zoning/development control
- EIS
- water quality management
- parcel records
- facility location
- urban spatial structures (ex. historic districts and developing master plans)
Give street networks examples of GIS
- emergency response systems (address matching)
- vehicle routing (ex. buses)
- evacuation plans
Give facilities management examples of GIS
for gas, electric, phone line, and other utilities
- routing pipes and wires
- planning facility maintenance
- tracking energy use
Give business geographics examples of GIS
- retailing
- insurance
- banking
- real estate
- sales/marketing
Give aviation examples of GIS
- pavement
- flight path
- land use
- utilities
- etc.
How can GIS be used for environmental justice?
The right to safe, sustainable environment regardless of identity - GIS can be used to identify that there are usually more risks in poor, racialized communities
What are the limitations of using a GIS?
- knowledge-based
- technology
- cost
- organizational factors
- lots of people don’t know how to use it properly
Why is GIS important?
- almost every decision made is influenced by geography
- heavily used by mun, prov, and fed gov’t as well as in the private sector and for research
