Cartography and maps
Arturo Flores and Bradley Miller
- Discuss the importance of maps for geography.
- Define the concept of geographic maps.
- Identify the different elements of a map.
Keywords: cartography, map, scale, legend, coordinates.
Cartography and map creation
Cartography is a subdiscipline of geography that graphically represents geographic data on flat surfaces. The preferred method of geography to represent spatial phenomena is with maps. A map is defined as a flat representation of spatial phenomena. Maps support visualizing data that is linked to a specific location within a geographic extent. These are easily interpreted by the users and help explain how features are spatially distributed.
Maps represent topographic features (related to the landscape) or thematic themes (quantitative or qualitative data). Topographic maps represent landforms or geographic accidents in the landscape. Thematic maps include cities and roads, land use, soil properties, and even religions distribution. It includes the absolute location of a feature (position in the Earth’s surface using coordinates) or a relative location (position using another object as reference). A map of a 10-acre farm with a pond next to a field may be useful to navigate through space locally. However, it will lack context about where that farm is located in respect to the world. On the contrary, a world map may provide the location of the farm on the Earth’s surface but will fail to be a precise navigation tool when trying to locate features, e.g., the pond.
Elements of a map
For a map to be efficient in transmitting spatial information, it has to include at least the following items:
Data. Also, the actual map. It is the flat representation of the geographic space and the spatial phenomena occurring in it and is the most important part because without it the map would not exist.
Title. The title is the first approximation of the user to the map’s content. It should provide some background on what the map represents. The title “Organic Matter Content” provides enough information to know which soil property is being mapped. However, it may not be completely clear where this field is located for someone other than the author. Hence, other guidance is required.
Coordinates and Reference Point. The coordinates help locate the geographic feature in the world. They are commonly included in the border of the map as ticks or as a grid overlaying the image. Different coordinates systems exist, and it should also be included in the map. A reference point can include a compass or arrow pointing towards the north, letting the reader situate itself better in the geographic space.
Scale. A basic concept of cartography for paper maps (fixed map scale) is that the level of detail is dictated by the map scale. For example, if we made a map of Polk County, Iowa, it would make sense to delineate the city boundaries of Des Moines. In contrast, if we made a map of the world, we would only mark the