Introduction to Maps

Introduction to Maps

  • Understanding maps is essential for representing spatial information and relationships.

Objective and Essential Learning

  • Types of Maps: Identify various map types and the information they present.
  • Spatial Patterns: Recognize different spatial patterns and relationships represented on maps.
  • Information Selectivity: Acknowledge that all maps are selective in the information they present and that projections distort spatial relationships.

Types of Maps (1.1.1)

Reference Maps

  • Provide general information about locations.
  • Types include:
    • Political Maps: Show states, countries, capitals.
    • Physical Maps: Highlight natural features like mountains and rivers.
    • Road Maps: Display highways, streets, and routes.

Thematic Maps

  • Focus on specific themes or information about a place.
  • Types include:
    • Choropleth Maps: Use colors/shades to represent spatial data distribution.
    • Dot-Density Maps: Each dot represents a quantity of a specific characteristic.
    • Graduated/Proportional Symbol Maps: Use varying symbol sizes to indicate different amounts.
    • Cartograms: Distort country sizes based on specific data.
    • Isoline & Topographic Maps: Show lines connecting points of equal value (e.g., weather, elevation).

Spatial Patterns on Maps (1.1.2)

Types of Patterns

  1. Absolute Location: Exact position based on coordinates.

    • Example: Rio de Janeiro is at 23°S, 43°W.

  2. Relative Location: Position of a place concerning another.

    • Example: "Next to my house"; geographical relations.

  3. Absolute Distance: Measured in units (miles/km).

    • Example: "Oak Hills is 21.3 miles from my house."

  4. Relative Distance: Conceptual distance, often influenced by factors like technology.

    • Example: Online shopping reducing effective distance to goods.

  5. Absolute Direction: Precise cardinal directions (N, S, E, W).

  6. Relative Direction: Describes location based on landmarks or other features.

    • Example: "Turn left at Target, right at the stop sign."

  7. Clustering: Objects close together within a defined area (density).

  8. Dispersal/Distribution: Objects spread out across an area.

  9. Patterns & Spatial Associations: Indications that multiple phenomena may relate.

Map Projections & Distortions (1.1.3)

  • Map Projection: Method for representing the Earth's curved surface on a flat surface.
  • All map projections involve a distortion of reality, affecting:
    • Shape: How regions appear.
    • Area: Size of regions represented.
    • Distance: Lengths between locations.
    • Direction: Orientation of map elements.

Types of Map Projections

  1. Mercator Projection (1569)

    • Advantages: Accurate direction, good for navigation.
    • Disadvantages: Distorts size, particularly near poles.

  2. Peters Equal Area Projection

    • Advantages: Accurate area size, correct representation of landmass proportions.
    • Disadvantages: Shapes distorted, especially near poles.

  3. Robinson Projection

    • Advantages: Minimal distortion across most aspects.
    • Disadvantages: All features slightly distorted, which compromises accuracy.

  4. Other Projections: Include Conic, Azimuthal, Fuller projections with various advantages and disadvantages.

Conclusion

  • All maps serve specific purposes and distort reality in some aspects. Understanding these characteristics helps in effectively interpreting maps and geographic data.