Map Concepts in AP Human Geography

Overview

This lecture introduces key concepts in AP Human Geography, focusing on map types, map projections, and understanding how spatial information is represented and interpreted.

Map Projections

• Maps are flat representations of the rounded Earth, causing unavoidable distortion.
• The Mercator projection preserves direction but distorts size, making areas like Greenland appear larger than Africa.
• The Goode Homolosine projection preserves area and shape but distorts distance and is interrupted.
• The Fuller projection accurately shows landmass size/shape but not directions and still distorts areas away from the center.
• The Robinson and Winkel Tripel projections balance distortion, concentrating it at the poles, and maintain reasonable size/shape.
• The Gall-Peters projection accurately depicts landmass size but distorts shape and direction.
• Every map projection is distorted in some combination of area, distance, shape, or direction.

Map Types

• Maps are mainly categorized as reference maps (informational, navigation) and thematic maps (showing spatial patterns/data).
• Reference maps help with boundaries, geographic features, navigation, or directions (e.g., road, subway, or topographic maps).

Absolute vs Relative Terms

• Absolute direction: Fixed compass directions (e.g., east is 90°).
• Relative direction: Based on situation/context (e.g., “north of here”).
• Absolute distance: Precise measurement (e.g., miles or kilometers).
• Relative distance: Approximate, often based on time or non-exact measures (e.g., five minutes away).
• Absolute location: Exact point using coordinates (e.g., latitude and longitude).
• Relative location: Describes location in relation to surroundings (e.g., “near the water tower”).

Thematic Maps and Spatial Data

• Thematic maps display specific topics using quantitative data.
• Choropleth maps use color to show quantity/density but generalize data (e.g., life expectancy per country).
• Dot density maps use dots for data points, showing spatial distribution but can be unclear in dense areas.
• Graduated symbol maps use differently sized symbols to show magnitude but can overlap and cause confusion.
• Isoline maps connect areas of equal value (often weather data), but may be hard to read.
• Cartogram maps alter land area to represent data value, clearly showing differences but distorting shapes.
• Flow-line maps use arrows to show movement (e.g., trade, migration), with size indicating volume.

Key Terms & Definitions

• Map Projection — A method for representing the curved Earth on a flat surface, always with some distortion.
• Reference Map — A map designed for navigation or finding locations and boundaries.
• Thematic Map — A map displaying spatial patterns for specific data or topics.
• Scale — The relationship between distance on a map and actual distance on Earth.
• Choropleth Map — Uses color shading to represent data values.
• Dot Density Map — Uses dots to show the frequency of a variable.
• Graduated Symbol Map — Uses symbols of varying sizes to represent data magnitude.
• Isoline Map — Connects points of equal value with lines.
• Cartogram — Changes the size/shape of areas to show data values.
• Flow-line Map — Uses arrows to depict the movement of objects or people.

Action Items / Next Steps

• Answer the review questions provided at the end of the lecture.
• Review key map types and projection characteristics.
• Practice distinguishing between absolute and relative terms.