Introduction to Maps and Map Projections (IMP-1.A.1–1.A.3)

Geography: The Why of Where - Studies spatial distribution, patterns, and implications for people.

Geographical Concepts - Geographers view place through space.

Introduction to Maps (Topic 11)

  • IMP-1.A.1: Types of maps:

    • Reference maps: general info.

    • Political Map: human-created boundaries (countries, cities).

    • Physical Map: natural features (mountains, rivers).

    • Thematic maps: show spatial aspects of specific phenomena.

Thematic Map Types (IMP-1.A.1)

  • Choropleth Map: Uses colors/patterns for spatial data; darker usually means higher value.

  • Dot Map: Each dot = quantity; shows specific locations.

  • Graduated Symbol Map: Symbol size varies by amount; uses key.

  • Isoline Map: Connects points of equal value (e.g., topographic maps); close lines = rapid change.

  • Cartogram: Area size reflects a statistic.

Spatial Patterns on Maps (IMP-1.A.2)

  • Absolute Location: Exact point (e.g., latitude/longitude).

    • Latitude (Parallels): N/S distance from Equator (0exto0^ ext{o}).

    • Longitude (Meridians): E/W distance from Prime Meridian (0exto0^ ext{o} Greenwich).

    • International Date Line: 180exto180^ ext{o} longitude. Time zones: roughly 15extoextperhour15^ ext{o} ext{ per hour}.

  • Relative Location: Location in relation to other places; can change with accessibility.

Map Projections and Distortions (IMP-1.A.3)

  • All maps distort (shape, area, distance, direction) when projecting Earth's curved surface onto a flat map.

Projection Examples and Distortions

  • Mercator: For navigation (accurate directions); distorts size near poles.

  • Peters: Preserves area; distorts shapes (especially near poles).

  • Conic: General mid-latitude use; distorts direction.

  • Goode-Homolosine: Preserves area/shape for landmasses; oceans interrupted.

  • Robinson: Balances size/shape; distorts poles (e.g., Antarctica exaggerated).