FUNDAMENTALS OF GIS

Introduction to the courseJanuary 9, 2012

Points to Cover What is GIS? GIS and Geographic Information

Science Components of GIS

Spatial data

Defining GIS Many definitions exist Three main points:

GIS is a computer system consisting of hardware and software

GIS works with spatially referenced dataGIS carries out various management and

analysis tasks on these data GIS is much more than a graphic

package or a mapping systemTurn raw data into information

GIS and Geographic Information Science Geographic Information Science refers

to the body of knowledge underpinning GISDraws and synthesizes knowledge and

methods created by other disciplinesInvolves research into:

Fundamental issues arising from the creation, handling, storage and use of geographic information (Longley et al., 2005)

Impacts of GIS on individuals and society and the influences of society on GIS (Goodchild, 1997)

Components of a GIS Various points of view

exist More comprehensive

definitions include:Computer system

○ Hardware and operating system

Software Spatial dataData management and

analysis proceduresOrganizational

environment

Computer System GIS run on a variety of computer

systems Essential elements of the hardware

(Burrough, 1986)Processor with sufficient powerSufficient RAMGood quality graphic interface, including a

good videocardData input and output devices

Software GIS software includes the following

basic modules:Data input and verificationData storage and database managementData outputData transformation toolsData analysis and manipulation tools

Spatial Data: Concept of Data

Data are observations from monitoring the real worldHourly temperature readings at the Regina

airport

Total number of new social assistance recipients per month

Raw numbers Data taken by itself is relatively useless

for making decisions

Spatial Data: Data and Information Data are observations from monitoring the

Data processing may include Summary/aggregation

Analysis

Adding context such as subject, scale or unit of measurement

Metadata Information that describes the content, quality,

condition, origin, and other characteristics of data or other pieces of information.

Communication is an important step in converting data into information

Data → Processing & Display → Information

Spatial Data: Dimensions of Data

Data has three dimension (modes)Temporal: provides a record of when the

data were collected

Thematic: ties the data to the real world feature or event

Spatial: references the location of the features

The data can be classified based on the dimension that is used to organize it Thematic data: data organized by theme

Spatial data: Structure Ways of structuring data in a

GISLayer-based approach:

Layers containing data related to the same theme or on the same type of features

Defined extent

Object-oriented approach: Spatial entities are regarded as

discrete objects with empty spaces between them

Spatial data: Structure ArcGIS software uses the layer-based

approach to structuring spatial dataLayers can be stored as collection of

interrelated files Coverages

Shapefiles

Layers can be stored as a feature class in a geodatabase The geodatabase storage model is based on a

series of relational database concepts

The multitier architecture of the geodatabase is sometimes referred to as an object-relational model

(ArcGIS Help files, ESRI ,1995-2010).

Data management and analysis GIS handles two types of data

Spatial data Gets visualized in the graphic interface as

map features

Non-spatial attribute data Provide information about features

Functions performed by GISData input, management and output

Data transformation and analysis Transformation is a process of changing

how the data are represented

Data management and analysis GIS handles two types of data

Spatial data Gets visualized in the graphic interface as

map features

Non-spatial attribute data Provide information about features

Functions performed by GISData input, management and output

Data transformation and analysis

Organizational Environment GIS utilization ranges

From small research projects carried out be a single person

To large-scale corporate distributed systems designed and used by different groups of users

Introducing GIS into an organization brings changes to all aspects of businessSuccessful implementation of GIS

requires taking into account existing needs and available resources