1. INTRODUCTION TO GIS

Our Complex Society

Our world is becoming…MorePopulatedUrbanizedTechnicalSpecializedConnected GlobalizedInformedFragile

GIS is focused on Integration, making it accessible.GIS is valuable as a FRAMEWORK for Managing Human Activities.

What is GIS?Geographic spatialInformation dataSystem group of related elements > a powerful set of tools for collecting, storing, retrieving at will, transforming and displaying spatial data from the real world

GIS COMPONENTSPeople – manage the system and develop plans for applying it to real world problemsSoftware – made up of integrated collections of computer programs that provides the functions and tools needed to store, analyze, and display geographic infoData – info about the contents of the earth and related parametersProcedures – methodologies, plans, business rules, models, operating practicesHardware – the comp on w/c a GIS operates, including the resources available to the computer

HOW DOES GIS WORK?A GIS stores info about the world as a collection of thematic layers that can be linked together by geography.This simple but extremely powerful and versatile concept has proven invaluable for solving many real-world problems.

Physical reality real world model data model database maps/reports

Actual phenomenon:Properties

Connections

To bring the real world into GIS, one has to make use of simplified models of the real world…

Why GIS?Able to store large amounts of spatial dataIntegrate diverse types of dataProvide better methods for managing and manipulating dataFacilitate the creation and updating of spatial dataProvide a better organizational decision-making tool

Questions GIS can answerLocation: Where is … ?Condition: What is …?Trends: What has changed since…?Patterns: What spatial pattern exists…?Modeling: What if…?

GIS IN THE PHILResource Management / Land Use PlanningNatural Resource ManagementUrban AgriculturePoverty MappingCoastal Resource ManagementAgricultureWater Resource ManagementEnvironmental ManagementSolid Waste Management

2. Participatory GIS

Moving beyond maps:Toward a People-Centered GIS

“If GIS is needed ubiquitous and easy to use…then it has the potentials to revolutionize the ways in w/c communities develop consensus…resolve disagreements and difficulties and plan for the future”

The objective…EmpowermentManagement

Community-based solutionsGIS can assist community organizationsDevelop appropriate responses

The importance…Venue for consultation and dialogueSocial and cultural practices of the peopleResourcesIssuesConcernsAspiration

Community Based-ToolsCommunity Mapping – sketch mappingParticipatory 3D Modeling

Some community mapping and P3DM applicationsDialogueResource managementPlanningResearchIssues managementCultural documentationProgram evaluation

Characteristics of Traditional GIS Applications and Community GIS PracticeTraditional GIS Characteristic Participatory GIS

Technology and people Focus People, process and technology

Facilitate official policymaking. Improve software programs

Motivation/Goal Empower communitiesFacilitate public participation.

Public officials, decision makers

Participants Local, underprivileged groups

Supply driven, technological push

Implementation Demand and need driven

Because it is possible Why adopt? Because it is neededDecided by GIS experts Details of Applications Decided by users/focus

groupsLed and controlled by GIS experts

Role of GIS Experts GIS experts act as facilitators

Top down, hierarchically structured

Information Flow Bottom up, grassroots and citizen participation.

“It is not enough for a handful of experts to attempt the solution of a problem, to solve it, and the apply it. The restriction of knowledge to an elite group destroys the spirit of society and leads to its intellectual impoverishment.” -- Albert Einstein, 1931

Empowerment is the process by w/c stakeholders identify and shape their livs and the society in w/c they live through access to knowledge, political processes and financial, social and natural resources (Arnstein, 1969).

Community Mapping PhasesCommunity Mapping is a process consisting of seven phases:Networking and Initial Consultations: Building solid relationships with key people in the area (e.g., expresses willingness to participate in a community mapping activityData Preparation: All available data is studied and acquainted (topographical maps, socio-economic and demographic data, livelihood, etc.)Initial Consultation with the community and Site Analysis: Aim to gain familiarity with the culture ad the features of its environment.Community Mapping Activity: actual mapping activity-the community produces a map of the area where they live.Community Validation: Opportunity for the community to check and validate the digitized community map. Activity provides the opportunity to discuss further details and concerns that are relevant to the activity.Technical Integration: Spatial accuracy of a topographical map is related to the community map. Geographic Information System- A comp system capable of holding and using data in describing places on the earth’s surface. The integrated map is subject to field verification and community validation. The validation activity will result in the finalization of maps.Presentation and Submission: The validated community map and integrated map are given to the community. Opportunity to discuss with them the significance and uses of maps produced.

ApplicationsFor awareness raising and educationfor community cohesion and self-actualizationfor increasing local communications capacityfor collaborative planningfor collaborative researchfor participatory monitoring and evaluationfor conflict resolution

3. Data Models and Georeferencing

Data Types:Raster Data – cells or pixels in a grid matrix. Points or cells organized into rows and columns. Each cell has an attribute value that represents a geographic phenomenon. Resolution/ pixel size of the grid determines the level of detail.Vector Data – represents the location ad shape of features and boundaries precisely. Geo-objects are represented as points, lines or polygonsReal WorldAttribute Data – Record info about feature. Provide a linkage between spatial and non-spatial data. Linkages make the GIS “intelligent,” as the user can store and examine info

Raster Data vs. Vector DataRaster Vector

Data collection rapid slowData volume large smallGraphic treatment average goodData structure simple complexGeometrical accuracy low highAnalysis in network poor goodArea analysis good averageGeneralization simple complex

BASIC DATA MODELSVector Model – real world can be divided into clearly defined elements. Consists of an identifiable objects with its own geometry of points, lines, or areas. Coordinate systems are displayed in grids. Points, lines and polygons are homogeneous ad discrete units that carry information.Raster Model – surfaces arranged in regular pattern. ‘Grid model’ because squares or rectangles. Common sizes are 10 X 10 m and 100 X 100 m

DATA MODELS FOR SURFACESGrid Model – systematic grid, or raster, of spot heights at fixed mutual spaces often used to describe terrain. Elevations are constant within each cell of the grid. Size of the cells is constant in a model. Suitable for describing random variations in the terrain.TIN Model – array of triangular areas with their corners. Incliation of the terrain are constant w/in each triangle. Requires larger storage capacity than the grid model. Good for describing terrain.

Georeferencinga mechanism to situate measurements on a geometric body, such as the earthestablishes a point of origin, orientation of reference axes, and geometric meaning of measurements, as well as units of measure

In GIS every dataset has a coordinate system, w/c is used to integrate it with other geographic data layers w/in a common coordinate framework such as a map.

Types of coordinate systems:geographic coordinate system – a global or spherical coordinate system such as latitude-longitude

Latitude and longitude – measures of the angles (in degrees) from the center of the earth to a point on the earth’s surfaceLatitude angles – measured in a north-south direction.Longitude angles – measured in an east-west direction.

The Shape of the EarthPossible representations:Geoid – figure that adjusts the best ellipsoid and the variation of gravity locally. Computationally very complex.Sphere – simplistic representation. Assumes the same length of both its axis.Ellipse – assumes different lengths for each axis. More appropriate since the earth is flatter at its poles due to its rotation speed

DatumBase elevation model for mappingRepresentation of the earth’s surfaceUsing a set of control points

projected coordinate system – provide various mechanisms to project maps of the earth’s spherical surface onto a two-dimensional coordinate plane. Sometimes referred to as map projections. An imaginary light is ‘projected’ onto a “developable surface”. Coordinate space becomes implicit. A variety of diff projection models exist.

UTM – best known map projection coordinate systemBased on a special type of cylindrical projection known as the Universal Transverse Mercator (UTM)Coordinates are defined in meters

PHILIPPINE SPATIAL REFERENCE FRAMEWORKCylindrical projection, Transverse Mercator (TM) – projection most commonly used

2 Projected Coordinate Systems:1. Universal Transverse Mercator (UTM) – a series of global projections that divide the

earth into 60 zones, 6 degrees for each zone- designed for regional areas of study- uses a Cartesian coordinate system where the origin of X and Y is located at the

intersection of the equator and the central meridian- unit of measurement is the meter- only one zone to cover the country

2. Philippine Transverse Mercator (PTM)- designed specifically for the Phil- primarily used for surveying political boundaries- uses 5 separate zones:

- Zone I 117° East Area west of 188° E- Zone II 119° East Palawan and Calamian Islands- Zone III 121° East Luzon (except SE), Mindoro- Zone IV 123° East SE Luzon, West Mindanao- Zone V 125° East East Mindanao, Bohol, Samar

- Uses the Luzon 1911 datum and the Clarke 1866 ellipsoid with a scale factor at the central meridian of 0.99995.

2 Basic datums:1. World Geodetic System of 1984 (WGS84)

- commonly used worldwide datum developed from satellite measurements of the earth- rapidly becoming the preferred datum around the world- origin is the center of the earth- the ellipsoid is also called WGS84

2. Luzon 1911most commonly used datum for the Philuses the Clark 1866 ellipsoidorigin is located just south of Luzon at Balacanan, Marinduque Island

4. HARDWARE AND SOFTWARE

GIS HARDWAREInput – data capture devices for both map and on-map dataOutput – data display/printing devices for both map and non-map data

GIS SOFTWAREgeoprocessing engine of a complete, working GISmade up of integrated collections of computer programs that encapsulate geographic processing functions

GIS software packages aim to provide a unified approach to working with geographic information.

Main components of a GIS software system:User Interface Applications

Geographic Tools – output, translation, analysis, editing, display, customizationData Access – spatial reference, vector, data manager, network

Classical 3-tier architecture of a GIS software systemTIER1 (User Interface – presentation): The user interacts with the graphical user

interface(GUI), an integrated collection of menus, tool bars and other controls. The GUI provides access to the GIS tools.

TIER2 (Tools – business logic): The tool set defines the capabilities or functions that the GIS software has for processing data management software.

TIER3 (Data Management – data server): The data are stored in files or databases organized by data.

3 types of GIS implementation configuration1. project2. department3. enterprise

Classification of GIS software packagesProfessional GIS – high-end, fully functional systemsDesktop GIS – mainstream workhouses of GIS todayHand-held GIS – lightweight systems designed for mobile and field useComponent GIS/ Developer GIS – used by developers to create focused applicationsGIS viewer – have limited functional capabilities restricted to display, query and simple mappingInternet GIS – integrates GIS technology with Web browsers and servers and uses the hypertext transmission protocol (http) for communicationServer GIS – GIS that runs on a computer server that can handle concurrent processing requests from a range of networked clients

MAIN GIS SOFTWARE VENDORS (Companies that design, develop and sell GIS softwares)

ESRI (www.esri.com)Intergraph (www.intergraph.com)Autodesk (www.autodesk.com)Smallworld (www.gepower.com)

5. Other Vendors:

IBMLeicaMapInfo

ESRI GIS SOFTWAREWhat is ArcGIS?ArcGIS is an integrated collection of GIS software products for building a complete GIS. ArcGIS enables users to deploy GIS functionality wherever it is needed in desktops, servers, or custom applications; over the Web; or in the field.

ArcGIS Desktop is a collection of software products that runs on standard desktop computers. It is used to create, import, edit, query, map, analyze, and publish geographic information.

INTRODUCTION TO ARCGIS9

Three views of GIS used for working with elements of geographic knowledge.

HYPERLINK "http://www.esri.com/software/arcgis/concepts/gis-data.html" \t "_parent" Geodatabase view: A GIS is a spatial database containing data sets that represent geographic information in terms of a generic GIS data model (features, rasters, topologies, networks, and so forth). ◊ ArcCatalog

HYPERLINK "http://www.esri.com/software/arcgis/concepts/geovisualization.html" \t "_parent" Geovisualization view: A GIS is a set of intelligent maps and other views that shows features and feature relationships on the earth's surface. Various map views of the underlying geographic information can be constructed and used as "windows into the database" to support queries, analysis, and editing of the information. ◊ ArcMap

HYPERLINK "http://www.esri.com/software/arcgis/concepts/geoprocessing.html" \t "_parent" Geoprocessing view: A GIS is a set of information transformation tools that derives new geographic data sets from existing data sets. These geoprocessing functions take information from existing data sets, apply analytic functions, and write results into new derived data sets. ◊ ArcToolbox

ArcCatalogThe ArcCatalog application organizes and manages all GIS information such as maps, globes, data sets, models, metadata, and services.

It includes tools toBrowse and find geographic information Record, view, and manage metadata Define, export, and import geodatabase schemas and designs Search and browse GIS data on local networks and the Web Administer an ARCGIS server

Users employ ArcCatalog to organize, find, and use GIS data as well as document data holdings using standards-based metadata.

A GIS database administrator uses ArcCatalog to define and build geodatabases.

A GIS server administrator uses ArcCatalog to administer the GIS server framework.

ArcMapthe central application in ArcGIS Desktop for all map-based tasks including cartography, map analysis, and editing. a comprehensive map authoring application for ArcGIS Desktop.ArcMap offers two types of map views

Geographic data view — an environment where geographic layers are symbolized, analyzed, and compiled into GIS data sets. A table of contents interface organizes and controls the drawing properties of the GIS data layers in the data frame. The data view is a window into any GIS data set for a given area.

Page layout view — an environment where map pages contain geographic data views as well as other map elements such as scale bars, legends, north arrows, and reference maps. The page layout view is used to compose maps on pages for printing and publishing. ArcToolboxArcToolbox contains a comprehensive collection of geoprocessing functions including tools forData management Data conversion Coverage processing Vector analysis Geocoding Statistical analysis ArcToolbox is embedded in ArcCatalog and ArcMap and is available in ArcView, ArcEditor, and ArcInfo.

5. VISUALIZATION AND MAP LAYOUT

VIZUALIZATION – the translation or conversion of spatial data from a database into graphics

MAPS – enable the user to perceive the structure of the phenomenon or the area being representedHow do I say what to whom, and is it effective?

Why Visualize?Maps are…valuable sources of Infouseful for storing and displaying infoimportant bases for planning and decision-makinggood records of landscape changes

Types of MapsGeneral Reference MapsAlso known as topographic mapspresets general image of the earth’s surface

Thematic MapsUsed to emphasize the spatial distribution of one or more geographic attributes or variables

Basic Steps for Communicating Map Info

Important factors to consider:Who is going to use it?What is its purpose?What is its content?What is the scale of the map?What is the projection of the map?How accurate is the map?

Levels of Measurements

Type of Variables:Qualitative (nominal) – attribute values are diff. in nature, w/out one aspect more important than anotherOrdinal – attribute values are different from each other, but there is one single way to order them, as some are more important/intense than othersQualitativeInterval – data measured with a randomly selected starting point and arbitrary intervalRatio – data measured in relation to a zero starting point and fixed interval

Visual VariablesBasic Graphic Variables:colorsizevaluegrain/textureorientation

shape

Visual Variables for Color Mapshuelightnesssaturationtip: use associative colors!!!

DATA CLASSIFICATION- Purpose is to simplify the appearance of the mapClasses portray relationship among data.

Methods:Equal intervals – difference bet lowest and highest value in each class is the sameQuantiles – arranges from low to high. Equal number of observations in each class.Natural Breaks – looks for gaps (breaks) in the dataMean Standard Deviation – standard deviation used to set cutpoints above and below the average (mean)

Types of Thematic MapsChoropleth Map – values are calculated for the areas and expressed as stepped valuesProportional Symbol Map – scaling symbols that are proportion to the magnitude of data occurring at point locations whether these locations are true point or conceptual pointDot Map – one dot is set equal to a certain amount of a phenomenon, and dots are placed where that phenomenon is most likely to occurIsopleth Map – map showing lines with equal values

Map DesignBasic Map Elements

6. BASIC SPATIAL ANALYSIS

Spatial Analysis – transforming data into useful info to satisfy the requirements or objectives of decision-makers at all levels in terms of detail

process for looking at geographic patterns in data and relationships bet features

It helps us to:Identify trends on the datacreate new relationships from the dataview complex relationships bet data setspredict events in another location or at another point in timemake better decisions about the real world

Attribute Data Operation:Query by Location

- also known as select-by-theme- where features in one theme are selected based on their spatial relation to features in a second theme; new data is not created, just a set of features are selected

Query / Logical Operations- set algebra- boolean

Arithmetic Operations- perform simple mathematical functions on values in the database

Statistical Operations- sum, ave, min, max, std. deviation, etc- histograms (frequency charts) and correlations can also be derived from attribute data

Reclassification creating a new field (‘class’) in the data table dissolving boundaries bet polygons of same attribute valuereducing/increasing info content

Relating Tables- involves joining or liking records bet 2 tables

Spatial Join- this operation is a mix of spatial and attribute operations. The end result is a join of two database tables, but the basis for the join is ‘coincident space’

Overlay – is the core of GIS analysis operations- a spatial operation that combines various geographic layers to generate new info

Vector Overlay – can be performed on various types of map features: polygon-on-polygon, line-on-polygon, point-on-polygon- during the process of overly, the attribute data associated with each feature type are merged

Points on polygon – det w/c pt. features of specified characteristics fall in specified areas

Lines on polygons – det w/c line features of specified characteristics fall in specified areasPolygons on polygons – overlapping 2 or more polygons to create a new region

Raster Overlay – Also known as map algebra- the pixel or grid cell values I each map are combined using arithmetic and Boolean operators to produce a new value in the composite map

3 groups of mathematical operators in the map calculator:1. Arithmetic operators (+, -, ×, ÷) allow for the addition, subtraction,

multiplication, ad division of 2 raster maps or umbers or a combination of the 22. Boolean operators (and, not, or, xor) use Boolean logic (true or false) on the

input values. Output values of true are written as 1 and false as 0.3. Relation operators (<=, =, >, >=) evaluate specific relational conditions. If the

condition is true, the output is assigned 1; if the condition is false, the output is assigned 0.

Buffer – creates a new theme with new polygon features (geometric objects) based on a constant measure from features in a source theme- buffers can be created based on: a single set width, multiple widths, varying width

Buffer types (vector data)

point circlesline corridorspolygon donuts Buffer (Raster data) – calculates the distance from each source cell center to all other centers

Determine whether users find the maps USEFUL and INFORMATIVE

Construct the map

Collect DATA appropriate for the map purpose

Det. the PURPOSE for making the map

Consider the REAL WORLD

ImpactsEnvironmentSecurityNatural PlacesBiodiversityAvailable ResourcesSustainability

Symbol,Line,text

Object:TypeAttributesRelationshipGeometryQuality

Entity:TypeAttributesRelationships