Types of Maps

This is an image of the choropleth map of the GDP of countries around the world. The choropleth maps have spatial units filled with a uniform color or pattern. These maps are mainly used for data that has been scaled or normalized and for indicating differences in a kind of area data such as  ownership of land.

This map is an isarithmic map that shows the average of the annual temperatures for the United States. Isarithmic maps are also known as topographic maps or contour maps. These maps portray continuous and smooth phenomenon using isolines that represent constant values. Isarithmic maps have two different forms: isometric maps, which show point data, and isopleth maps where data occurs over geographical areas. The map shown is an example of an isopleth map because the temperature exists at every point and does not change abruptly. 

 This type of map is known as the proportional symbol map. A proportional symbol map uses symbols of different sizes to represent data that correlates with a certain location; or in other words, these maps scale icons according to the data that they represent. This particular map shows the number of lynchings in the different states in the US between 1882-1968. The number of lynchings in that state are depicted by the size of the square that is on the state. 

                            

                                                            

     

The next map is a dot density map. The dot density map is a map that uses a dot to represent the presence of a feature or a phenomenon.  The map on the right shows the Hispanic population in each state which is depicted by dots. Each dot represents a population of 100,000. Dot maps create a visual impression of density and should be used to represent raw data.

      

The Environmental Sensitivity Index Map is used to identify the sensitive resources that may be impacted in the case of an oil spill. This map shows the Gulf of Mexico shoreline and the areas that would be effected the most. The environmental sensitivity index map also can be a way to plan clean-up and preventive strategies in the case of an oil spill to save important natural resources.