Cartographic Generalization: Principles and Mapping Methods

Defining Cartographic Generalization

Cartographic generalization is the simplification of reality. It involves selecting geographic variables to represent on a map, ensuring the representation is both effective and useful.

Understanding Geographic Variables

A geographic variable is anything located at a site. This can be material (e.g., a house) or intangible (e.g., a political idea), as well as steady (e.g., a road) or dynamic (e.g., a cold front).

Mapping Approaches

There are five primary mapping approaches that are not necessarily incompatible:

• Geometric: Focuses on metric accuracy and measurement. It prioritizes precision over design.
• Technological: Views the map as a tool for storing spatial information, focusing on data collection, processing, and storage.
• Presentation: Prioritizes map design to convey information clearly through simplification and generalization, often at the expense of strict accuracy.
• Artistic: Emphasizes the aesthetic dimension, using visual attributes like color, balance, and contrast to evoke associations and feelings.
• Communication: Focuses on the map's capacity to convey information effectively, treating graphics as a vital tool for thought transmission.

Basic Graphic Elements in Cartography

Maps are constructed using three fundamental graphic elements:

• Points: Theoretically dimensionless, these are symbolized by visible signs with at least two dimensions.
• Lines: Defined as length without breadth, these are represented by linear signs possessing both length and width.
• Polygons or Areas: These are lines closed in on themselves. Possessing two dimensions (length and width), they can be filled with color or patterns to represent surfaces.