Presentation on theme: "Introduction to Geographic Information Systems and Processes"— Presentation transcript:
1 Introduction to Geographic Information Systems and Processes Unit I:What is GIS?
2 Why does location matter? Because everything that happens, happens somewhere. (yes, even on the internet).Knowing where something happened is important to understanding what the effects will be.There are two types of location problems:GeographicSpatial
3 What is a Geographic Problem? A Geographic Problem is any problem that involves any aspect of location, either in the information used to solve them or in the solutions themselves (pg 4).Example:The City of Tallahassee solves a geographic problem when it plans garbage truck and bus routes to optimize pickups and service to the most people with the least amount of fuel or quickest trip time, respectively.
4 Three issues to take into account with Geographic Problems 1) Geographic Scale : What level of geographic detail required?2) Intent : What is the purpose of this analysis?Practical/Applied : solving a problem to achieve a specific end (minimize cost, maximize profit, etc). This is a pragmatic view.Human Curiosity : Mapping glacial deposits and sea level change across the world to understand Global Climate Change ( or Warming , depending on what side of the issue you are on).3)Temporal (Time) Scale: When do the problems need to be solved? Over what span of time do the actions take place.Operational (short term): where is the closest hurricane shelter for a specific neighborhood?Tactical (medium term): where should the county widen roads so that evacuees can more easily and quickly vacate a flood plain next year.Strategic (long term): Where should building codes be updated to ensure proper storm water management to prevent future floods. (Where should new levees and storm surge walls be built to reduce the risk of inundation?)
5 Spatial is SpecialGeographic Problems are problems dealing with the surface (or near-surface) of Planet Earth. ( eg. The optimal bus route to serve FSU’s Campus)Spatial Problems are problems dealing with any (even abstract) space or spaces. (eg. the folding of proteins in reaction to a certain chemical)Therefore, every Geographic problem is Spatial but not all Spatial Problems are Geographic.We use the term Geospatial to cover both terms when discussing spatial analysis of geographic phenomena.
6 What is an Information System? Information Systems help us manage what we know, by making it easier to organize, store, access, retrieve, manipulate, synthesize, and apply knowledge to the process of solving a problem. (pg 11)What we know can be divided into 5 different catagories
7 5 divisions of What We Know 1) Data 2) Information 3) Evidence 4) Knowledge 5) Wisdom
8 5 divisions of What We Know Data:Consist of numbers, text, or symbols which are context free or neutral.In a computer context they are the bits that hold the lowest level of what we know.Eg. Raw geographic info such as temperature at a specific time and location.The most important part of a GIS.Garbage in, Garbage out.
9 5 divisions of What We Know Information:Data that is serving a purpose.Data that has been given some form or interpretation.A database is considered Information.Independent, it exists outside of a Knower.More ‘expensive’ to produce than data.
10 5 divisions of What We Know Evidence:Information from different sources, related to a specific problem, having a consistent level of validation.A geodatabase consisting of many layers of information covering a specific area that has been checked for accuracy in the field (ground truthing).Between Information and Knowledge.
11 5 divisions of What We Know Knowledge:Information or Evidence which has value added to it through a specific context, purpose, or experienceInformation in a book becomes Knowledge when it is read and understood by someone.Requires a “Knower”
12 5 divisions of What We Know Differences between Information and Knowledge:Knowledge entails a ‘knower.’ Information exists independently, but knowledge is related/requires peopleKnowledge is harder to detach from the ‘knower’ than information. Shipping, receiving, transferring knowledge between people are all harder than with information.Knowledge requires more assimilationWe may hold conflicting information, but we rarely hold conflicting knowledge.
13 5 divisions of What We Know Wisdom:The resulting decision made after knowing all the information and evidence that was derived from the data, taking into account the possible consequences of the decision.Highly individualized almost impossible to share others completely.Your view of the world.
14 What does this have to do with GIS? Idiographic Geography: focuses on the description of form and unique characteristics of a placeNomothetic Geography: tries to describe/discover general processes.One important characteristic of GIS is that it allows for combination of the general with the specific.Knowledge with data.The integration of Idiographic Geography with Nomothetic Geography
15 What does this have to do with GIS? The database of a GIS represents the specific knowledge or Data/InformationThe Software of a GIS captures and implements general knowledge through analysis and computation to create more knowledge and evidenceThe Analyst makes decisions based on the analysis and contributes to the wisdom about the topic.
16 So What is a GIS? It depends… 6 general definitions (Table 1.3) All consist of these elements:GIS SoftwareGIS DataGIS communityDoing GIS
17 So What is a GIS? GIS Software: A piece of software one can buy from a vendor to perform well defined functions on Geospatial data.GIS Data:Digital representations of the world or a space that is usually contained in a dataset.GIS Community:A groups of people that use or advocate the use of these tools for various purposes.Doing GIS:The act of using a GIS (all parts) to solve a problem or advance science
18 6 general definitions (table 1.3) Groups of peopleDefinition of GISGeneral PublicContainer of maps in digital formPlanners, community leaders, and decision makersComputerized tool for solving geographic problemsUtility and Transportation managersDigitized (mechanized) inventory of geographically distributed features and facilitiesoperations researchers; Management scientists (foresters)Spatial decision support systemResource managers, other plannersTool for performing operations on geographic data that is too tedious, expensive, or inaccurate if performed by handResearch Scientist and InvestigatorsTool for revealing what is otherwise invisible in geospatial information
19 So What is a GIS?It will vary depending on your Data, Problem, and Required Application
20 Brief History of GIS (Table 1.4) Era of InnovationCGIS – Canadian GIS – Roger TomlinsonURISA – USA – Urban and Regional Information Systems and ApplicationsHarvard Laboratory for Computer Graphics and Spatial analysisSYMAP- First Raster GIS HarvardESRI Inc Founded by Jack Dangermond (a student of the Harvard LabLANDSAT 1 Launched – First major remote sensing satellite.
21 Brief History of GIS (Table 1.4) Era of Commercialization1981 – ArcInfo Launched – first major commercial GIS, set new industry standard (ESRI)1985 – GPS Operational – Major source of geo-locational information and accuracy assessment.1988 – TIGER – US Census data in easily usable digital form – (Topologically Integrated Geographic Encoding and Referencing)1994 – Open GIS Consortium – GIS Vendors, Agencies and data providers working together to improve interoperability1996 – First online GIS products introducedMapquest
22 Brief History of GIS (Table 1.4) Era of Exploitation1999 – IKONOS- New generation of Remote Sensing satellite – 1 meter spatial resolution.2000 – GIS passes $7 Billion in revenue2004 – National Geospatial Intelligence Agency (NGA) – Biggest GIS user in the world, US government geo-intelligence agency (National Imagery and Mapping Agency)2005 – Google Maps and Earth – integrate Keyhole technology for the masses
23 What is GIS?Geographic Information Systems (GIS) are computer-based systems for the management, display, and analysis of geographic data.This includes the Computers, Data, and People that collect and analyze data.
24 Why Use GIS?GIS was originally developed as an extension of the use and analysis of the traditional paper map.The most basic form of digital map data represents the same types of data that are displayed on paper maps.Digital maps use the same measurement frameworks, and frequently also use the same representation methods (e.g., colors, classification schemes) used on paper maps.
25 Why is a GIS better than a Paper Map? GIS uses the analytical power of the computer to complete complex tasks which would be impossible or impractical using paper maps.GIS allows the integration of many different types of data from many different sources (maps, tabular data, aerial photos, elevation models, satellite imagery, CAD data, linear measurements, etc.) within an integrated storage, management, analysis, and display environment. Many of these data types are not easily represented on paper maps.GIS registers a variety of different data to the same coordinate space, which allows for the analysis of the combination of different layers (e.g., slope, forest windthrow hazard, distance to streams, and forest age). Frequently with paper maps, different thematic maps appear on different map sheets that are in different scales or use different representation frameworks.Digital data are more stable than paper media, easier to copy, and easier to distribute. Many web sites exist that distribute digital geospatial data.
26 Why is a GIS better than a Paper Map? Digitally created maps are more easily updated than paper maps (change the data and print a new copy).GIS allows the creation and use of "one-time" maps (whereas paper maps generally need to be printed and sold by the thousands to recapture the cost of production). For example, a map can be prepared with GIS specifically for a particular public presentation; the map may never be used after that presentation.GIS allows individual users to tailor their map displays for their own purposes, rather than having to settle for a general-purpose paper map.GIS eliminates some user bias in measurement or analytical processes (the computer repeats measurement and analytical processes identically, whereas people often repeat processes with random or systematic errors).GIS brings new tools for thinking differently about the world and its interrelationship.
27 What can GIS Do?Locate geographic features based on their properties (e.g., "Where are all the cities within western Washington of population greater than 5000, but less than 10,000?").Identify properties of geographic features based on their location (e.g., "How many people live in the cities within 20 miles of Seattle?").Determine a good location of a Wal-Mart, based on the demographics and land-use/availability of a given area.Generate optimal routing and scheduling for an appliance delivery and repair truck.Determine the ground area covered by a new cellular phone network. Locate "holes" in cellular coverage.Delineate watershed boundaries for the major tributaries of a River, and generate land-cover area statistics for those watersheds.Predict landslide hazard for forest harvest units, based on slope, precipitation, and soil type.Make colorful, interesting, and informative maps that are easily reproduced.
28 Anatomy of a GIS The Network: Includes the Internet, WWW, and Intranets of agencies, companies, and groupsInternet began as ARPANET (Advanced Research Projects Agency Network)Hypertext developed by Tim Berners-Lee
29 What can GIS Do?Locate geographic features based on their properties (e.g., "Where are all the cities within western Washington of population greater than 5000, but less than 10,000?").Identify properties of geographic features based on their location (e.g., "How many people live in the cities within 20 miles of Seattle?").Determine a good location of a Wal-Mart, based on the demographics and land-use/availability of a given area.Generate optimal routing and scheduling for an appliance delivery and repair truck.Determine the ground area covered by a new cellular phone network. Locate "holes" in cellular coverage.Delineate watershed boundaries for the major tributaries of a River, and generate land-cover area statistics for those watersheds.Predict landslide hazard for forest harvest units, based on slope, precipitation, and soil type.Make colorful, interesting, and informative maps that are easily reproduced.