Emerald Robinson: Hi, I am Emerald Robinson, and in this What is? video, we're going to answer the question, What is Topography?
Topography is the study of a land's surface shape, its hills and mountains, valleys, rivers, and craters. Topographers analyze these features, whether they're on the earth, the moon, an asteroid, or on a distant planet.
The primary goal of topography is to find out the latitude (the distance north or south of the equator,) the longitude (the distance east or west of the Prime Meridian,) and elevation (the distance above sea level) of various landforms.
Topographers study about the geology and the geography of land's features. These qualities also make up what we call an areas terrain. Many times, topographers use information about the earth's terrain to create a topographic map.
Topographic maps are useful because they are able to show elevation on a flat piece of paper. Elevation is indicated by a line, usually curved, called a contour line. For example, a mountain's peak that has an elevation of 10,000 feet would be represented by a contour line drawn in the shape of all continuous points of the peak that are 10,000 feet above the ground.
Contour lines are usually labeled with the elevation they represent, and can be used to tell the slope of a landform. Close contour lines mean a steep slope, while contour lines that have more space between them mean a more gentle slope.
Topography is used to determine where to safely construct new buildings; to figure out where rivers and streams flow; to help dig mines and to build dams, and to plan and repair roads.
You may have even used topography at a local, state, or national park to plan a hike, or to find out where to canoe, fish, and do other outdoor activities.