In geography maps are one of the most important tools researchers, cartographers, students and others can use to examine the entire Earth or a specific part of it. Simply defined maps are pictures of the Earth's surface. They can be general reference and show landforms, political boundaries, water, the locations of cities, or in the case of thematic maps, show different but very specific topics such as the average rainfall distribution for an area or the distribution of a certain disease throughout a county. Today with the increased use of GIS, also known as Geographic Information Systems, thematic maps are growing in importance.
There are however applications for different types of general reference maps when the different types are understood correctly. These maps do not just show a city's location for example; instead the different map types can show a plethora of information about places around the world.
The following is a list of each major map type used by geographers and a description of what they are and an example of each kind.
• Political Map: A political map does not show any topographic features. It instead focuses solely on the state and national boundaries of a place. They also include the locations of cities - both large and small, depending on the detail of the map. A common type of political map would be one showing the 50 U.S. states and their borders along with the United States' north and south international borders (map of the United States).
• Physical Map: A physical map is one that shows the physical landscape features of a place. They generally show things like mountains, rivers and lakes and water is always shown with blue. Mountains and elevation changes are usually shown with different colors and shades to show relief. Normally on physical maps green shows lower elevations while browns show high elevations. An example of a physical map is one showing the state of Hawaii (map of Hawaii). Low elevation coastal regions are shown in dark green, while the higher elevations transition from orange to dark brown. Rivers are shown in blue.
• Topographic Map: A topographic map is similar to a physical map in that it shows different physical landscape features. They are different however because they use contour lines instead of colors to show changes in the landscape. Contour lines on topographic maps are normally spaced at regular intervals to show elevation changes (e.g. each line represents a 100 foot (30 m) elevation change) and when lines are close together the terrain is steep. For example a topographic map showing the Big Island of Hawaii would have contour lines that are close together near the steep, high elevation mountains of Mauna Loa and Kilauea (map of the Big Island). By contrast, the low elevation, flat coastal areas show contour lines that are spread apart.
• Climate Map: A climate map shows information about the climate of an area. They can show things like the specific climatic zones of an area based on the temperature, the amount of snow an area receives or average number of cloudy days. These maps normally use colors to show different climatic areas. A climate map for Australia for example uses colors to show differences between the temperate area of Victoria and desert region in the center of the continent.
• Economic or Resource Map: An economic or resource map shows the specific type of economic activity or natural resources present in an area through the use of different symbols or colors depending on what is being shown on the map. For example an economic activity map for Brazil can use colors to show different agricultural products of given areas, letters for natural resources and symbols for different industries (image showing a map of Brazil).
• Road Map: A road map is one of the most widely used map types. These maps show major and minor highways and roads (depending on detail) as well as things like airports, city locations and points of interest like parks, campgrounds and monuments. Major highways on a road map are generally red and larger than other roads, while minor roads are a lighter color and a narrower line. A road map of San Francisco, California for example would show the major highways as a wide red line and other large roads as a lighter red with minor streets as gray (map of San Francisco).
• Thematic Map: A thematic map is a map that focuses on a particular theme or special topic and they are different from the six aforementioned general reference maps because they do not just show natural features like rivers, cities, political subdivisions, elevation and highways. If these items are on a thematic map, they are background information and are used as reference points to enhance the map's theme. An example of a thematic map would be one showing the population change of Canada in specific locations from 1996 to 2001. The map shows the theme it is attempting to get across to its audience and uses a political map (e.g. one showing the provincial and territorial borders of Canada) to give it more of a reference.
To learn more about maps and to see different maps, visit the Maps section of this website.
Briney, Amanda. (2 March 2011). "Thematic Maps: Thematic Maps Display Data on a Map." Geography at About.com. Retrieved from: http://geography.about.com/od/understandmaps/a/thematicmaps.htm
FactMonster.com. (n.d.). Types of Maps: From Climate to Topographic. Retrieved from: http://www.factmonster.com/world/geography/types-maps.html