GIS
Geography:-
 The study of the Earth’s physical features,
environments, and human interactions with those
environments.
 It explores landforms, climates, populations,
resources, and how people shape and are shaped
by the world around them.
Information:-
 Data that has been processed or organized to
provide meaning or context.
 In GIS, information refers to spatial data (like
coordinates, attributes, and maps) that help us
understand patterns or relationships.
System:-
 A set of connected components or processes that
work together to achieve a goal.
 In GIS, a system integrates hardware, software,
data, and people to capture, analyze, and visualize
geographic information.
Part I - GIS
CHAPTER ONE: Introduction to Geographic Information Systems (GIS)
Title: Introduction to Geographic Information Systems (GIS)
Subtitle: Part I - GIS | Chapter One
Presented by: Tajebe Negash WeldeMichael
What is GIS?
Definition: A system that captures, stores, analyzes, and
visualizes spatial data.
Supports decision-making through spatial analysis.
Example: Mapping flood zones, planning cities, tracking
diseases.
What GIS can do?
What Analysis GIS can do ?
Components of GIS
 Hardware: Computers, GPS devices.
 Software: ArcGIS, QGIS.
 Data: Spatial (maps) and attribute (descriptive)
data.
 People: Analysts, researchers, decision-makers.
 Methods: Techniques and workflows for
analysis.
Key Functions of GIS
 Data Capture: Collecting geographic data.
 Data Storage: Organizing data in databases.
 Data Analysis: Identifying spatial patterns.
 Visualization: Creating maps and charts.
 Decision Making: Supporting planning and management.
Types of GIS Data
1. Raster Data: Grid-based images (e.g., satellite
images).
2. Vector Data:
 Points (e.g., locations).
 Lines (e.g., roads).
 Polygons (e.g., land parcels).
GIS Applications
 Urban Planning: Managing infrastructure.
 Environmental Management: Monitoring ecosystems.
 Disaster Management: Flood and earthquake mapping.
 Agriculture: Precision farming and crop monitoring.
 Health: Disease tracking and healthcare access.
Concepts of GIS
 Spatial Data: Geographical data with coordinates.
 Layers & Overlay: Stacking data layers for analysis.
 Spatial Relationships: Proximity, intersection, etc.
 Georeferencing: Assigning coordinates to data.
 Data Integration: Merging multiple data sources.
 Spatial Analysis: Advanced analysis like route selection.
Objectives of GIS
 Data Collection & Management: Organizing geographic data.
 Spatial Analysis & Decision Support: Finding patterns.
 Visualization & Mapping: Creating maps and models.
 Environmental Management: Monitoring land use.
 Urban Planning: Designing infrastructure.
 Scientific Research: Climate change, public health.
Real-World Representation in GIS
 Vector Data Model: Points, lines, polygons.
 Raster Data Model: Grid of pixels with values.
 Attribute Data: Descriptive data tied to features.
Vector Data
 Advantages: High precision, small file size.
 Disadvantages: Complex processing, manual
digitization.
 Examples: Roads, buildings, land parcels.
Raster Data
 Advantages: Ideal for continuous data, fast analysis.
 Disadvantages: Large file size, pixelated boundaries.
 Examples: Satellite images, elevation models.
Attribute Data
 Advantages: Enhances GIS analysis.
 Disadvantages: Data errors, processing overhead.
 Examples: Population, land use, temperature.
Feature Vector Data Raster Data Attribute Data
Structure Points/lines/polygons Grid of cells Descriptive tables
Best For Boundaries, networks Elevation, imagery Feature descriptions
Accuracy High Lower (pixelated) Varies
File Size Small Large (high-res) Varies
Analysis Speed Slower Faster Database-dependent
Summary Table - Vector vs. Raster vs. Attribute Data
Real-World Feature Vector Representation Raster Representation
Tree Point Single cell
River Line Connected cells
Lake Polygon Group of cells
Population Density Data table linked to map Heatmap/grid
Real-World Objects vs. GIS Representation
Layers in GIS
 Example: City GIS database with
layers for:
o Roads (lines)
o Buildings (points)
o Land Use Zones (polygons)
o Population Density (attribute data)
Case Study - Flood Risk Mapping
 Goal: Identify flood-prone areas.
 Data Layers:
o DEM (elevation).
o River networks.
o Land use.
 Process:
o Generate slope and flow maps.
o Buffer rivers to mark risk zones.
o Overlay land-use data to assess impact.
Visualization and Results
 Flood Risk Map: Shows high/medium/low risk zones.
 Impact Analysis: Highlights affected infrastructure.
 Outcome: Informs flood prevention strategies.
Conclusion & Summary
 GIS: A powerful tool for spatial data analysis.
 Key Concepts: Layers, spatial analysis,
georeferencing.
 Applications: Planning, environment, disaster
management.
 Models: Vector, raster, and attribute data.

Part I - ch-1 GIS Lesson.pptx **introduction to geographic information systems (GIS)**

  • 1.
  • 2.
    Geography:-  The studyof the Earth’s physical features, environments, and human interactions with those environments.  It explores landforms, climates, populations, resources, and how people shape and are shaped by the world around them.
  • 3.
    Information:-  Data thathas been processed or organized to provide meaning or context.  In GIS, information refers to spatial data (like coordinates, attributes, and maps) that help us understand patterns or relationships.
  • 4.
    System:-  A setof connected components or processes that work together to achieve a goal.  In GIS, a system integrates hardware, software, data, and people to capture, analyze, and visualize geographic information.
  • 5.
    Part I -GIS CHAPTER ONE: Introduction to Geographic Information Systems (GIS)
  • 6.
    Title: Introduction toGeographic Information Systems (GIS) Subtitle: Part I - GIS | Chapter One Presented by: Tajebe Negash WeldeMichael
  • 7.
    What is GIS? Definition:A system that captures, stores, analyzes, and visualizes spatial data. Supports decision-making through spatial analysis. Example: Mapping flood zones, planning cities, tracking diseases.
  • 8.
  • 9.
  • 10.
    Components of GIS Hardware: Computers, GPS devices.  Software: ArcGIS, QGIS.  Data: Spatial (maps) and attribute (descriptive) data.  People: Analysts, researchers, decision-makers.  Methods: Techniques and workflows for analysis.
  • 11.
    Key Functions ofGIS  Data Capture: Collecting geographic data.  Data Storage: Organizing data in databases.  Data Analysis: Identifying spatial patterns.  Visualization: Creating maps and charts.  Decision Making: Supporting planning and management.
  • 12.
    Types of GISData 1. Raster Data: Grid-based images (e.g., satellite images). 2. Vector Data:  Points (e.g., locations).  Lines (e.g., roads).  Polygons (e.g., land parcels).
  • 13.
    GIS Applications  UrbanPlanning: Managing infrastructure.  Environmental Management: Monitoring ecosystems.  Disaster Management: Flood and earthquake mapping.  Agriculture: Precision farming and crop monitoring.  Health: Disease tracking and healthcare access.
  • 14.
    Concepts of GIS Spatial Data: Geographical data with coordinates.  Layers & Overlay: Stacking data layers for analysis.  Spatial Relationships: Proximity, intersection, etc.  Georeferencing: Assigning coordinates to data.  Data Integration: Merging multiple data sources.  Spatial Analysis: Advanced analysis like route selection.
  • 15.
    Objectives of GIS Data Collection & Management: Organizing geographic data.  Spatial Analysis & Decision Support: Finding patterns.  Visualization & Mapping: Creating maps and models.  Environmental Management: Monitoring land use.  Urban Planning: Designing infrastructure.  Scientific Research: Climate change, public health.
  • 16.
    Real-World Representation inGIS  Vector Data Model: Points, lines, polygons.  Raster Data Model: Grid of pixels with values.  Attribute Data: Descriptive data tied to features.
  • 18.
    Vector Data  Advantages:High precision, small file size.  Disadvantages: Complex processing, manual digitization.  Examples: Roads, buildings, land parcels.
  • 19.
    Raster Data  Advantages:Ideal for continuous data, fast analysis.  Disadvantages: Large file size, pixelated boundaries.  Examples: Satellite images, elevation models.
  • 20.
    Attribute Data  Advantages:Enhances GIS analysis.  Disadvantages: Data errors, processing overhead.  Examples: Population, land use, temperature.
  • 21.
    Feature Vector DataRaster Data Attribute Data Structure Points/lines/polygons Grid of cells Descriptive tables Best For Boundaries, networks Elevation, imagery Feature descriptions Accuracy High Lower (pixelated) Varies File Size Small Large (high-res) Varies Analysis Speed Slower Faster Database-dependent Summary Table - Vector vs. Raster vs. Attribute Data
  • 22.
    Real-World Feature VectorRepresentation Raster Representation Tree Point Single cell River Line Connected cells Lake Polygon Group of cells Population Density Data table linked to map Heatmap/grid Real-World Objects vs. GIS Representation
  • 23.
    Layers in GIS Example: City GIS database with layers for: o Roads (lines) o Buildings (points) o Land Use Zones (polygons) o Population Density (attribute data)
  • 24.
    Case Study -Flood Risk Mapping  Goal: Identify flood-prone areas.  Data Layers: o DEM (elevation). o River networks. o Land use.  Process: o Generate slope and flow maps. o Buffer rivers to mark risk zones. o Overlay land-use data to assess impact.
  • 25.
    Visualization and Results Flood Risk Map: Shows high/medium/low risk zones.  Impact Analysis: Highlights affected infrastructure.  Outcome: Informs flood prevention strategies.
  • 26.
    Conclusion & Summary GIS: A powerful tool for spatial data analysis.  Key Concepts: Layers, spatial analysis, georeferencing.  Applications: Planning, environment, disaster management.  Models: Vector, raster, and attribute data.