How Information on a Map Can Be Displayed Lesson 6

Cartographer Cartographers collect and interpret geographical information and prepare maps and other databases. Cartographers use many tools to study and communicate geographic information. They use photographs, satellite information, survey data, and other sources to collect information and translate it into maps and other tools needed for environmental planning and management. Cartographers increasingly use global positioning systems (GPS) and geographic information systems (GIS) to collect and use geographic data.

How Information on a Map Can Be Displayed Aerial photos, globes, polar projections, and location technologies are just a few of the examples of how information about the Earth can be displayed.  Each of these types of displays has different advantages and disadvantages.

Polar Projections Because the Earth is round, map projections on flat surfaces always have some type of distortion.  A polar projection is good for showing the North Pole or the South Pole, but it does not accurately represent areas that are far away from the poles. 

Polar Projections On the map to the right, the areas furthest from the center point have a great deal of distortion.

Aerial Photos Aerial photos show how land is being used in an area. The aerial photo to the right shows roads, water, small buildings, and skyscrapers. 

Aerial Photos While different types of maps might show features such as roads or rivers, these types of maps have limitations and cannot show everything.  Aerial photos can be used to see types of information that cannot be seen on regular maps.

Globes Because the Earth is round, the most accurate way to represent the Earth is on a round surface of a globe.  A globe is a scale model of the Earth that correctly represents area, the size and shape of physical features, distances between places, and compass directions.  A globe is very useful when looking at large areas or the entire world.

Geographic Information Systems A Geographic Information System (GIS) records, analyzes, and presents data about a specific location.  The information is presented in different layers so that multiple features can be studied together.  Video: Geographic Information Systems (GIS)

Geographic Information Systems This GIS displays monitoring wells, industries, and population of an area.

Global Positioning Systems The Global Positioning System (GPS) uses a system of 24 satellites to pinpoint exact locations across the world.  This information is then sent through radio waves that can be received by the U.S. government or by individuals.  GPS is commonly used by individuals today to provide driving directions. The Global Positioning System (GPS) uses a system of 24 satellites to pinpoint exact locations across the world.  This information is then sent through radio waves that can be received by the U.S. government or by individuals.  GPS is commonly used by individuals today to provide driving directions.

Digital Satellite Images A special type of “aerial photography” Photographs of Earth taken by satellites Used to see what an area looks like high above the Earth’s surface Advantages Creates more accurate maps Covers a large ground area- showing mountains, rivers and roads Can tell a great deal about what has happened to a city’s size, wealth, and population growth

Digital Satellite Imagery Bombay, India New Orleans, LA September 2005 Hurricane Katrina Pilger, Nebraska June 2014 Twin Tornadoes

Historical Maps Can show the growth of a city over time. Can provide information about places as they were in the past. May show the political boundaries of a place during a certain time. By comparing maps of the same area from different times, you can see how political boundaries change.

Historical Maps- continued The United States, 1848 The United States, 1845

Video: Mapmaking