Chapter 1 Section 8 What is a topographic map? Objective: Describe what is shown on a topographic map

Key Terms elevation: height of a point on Earth above or below sea level topography: general form and shape of the land on Earth’s surface contour line: line drawn on a map that connects all points having the same elevation

Elevation The level of the water in the oceans is about the same height everywhere on Earth. The average height for water in the oceans is called sea level. The height of a place on land is measured from sea level. For example, the height of Mount McKinley, Alaska, is more than 6 km above sea level.

DEFINE What is elevation?

Topography Examples of topography on Earth’s surface are mountains, valley, plains, and plateaus. Mountains have high elevations and steep slopes. Valley are low areas bordered by high ground. Plains are broad, flat areas that are usually only a little above sea level. Plateaus are broad, flat areas of land that have an elevation of at least 300 m above sea level.

2. IDENTIFY What are three types of topography on Earth’s surface?

Contour Lines The elevations of surface features can be shown on a map using contour lines. When you look at the contour lines on a map, you can identify the shape, or contour of the land. Every point on a contour line has the same elevation.

3. DESCRIBE What do contour lines on a map show?

Topographic Maps A map with contour lines shows the surface features, or topography, of the land. That is why these maps are called topographic maps. The contour lines found on a topographic map connect places on the map having the same elevation.

4. EXPLAIN What is a topographic map?

CHECKING CONCEPTS What is sea level? What is topography? What is a contour line? What is the height of a point above or below sea level called?

THINKING CRITICALLY 5. CONTRAST: What is the difference between sea level and elevation? 6. EXPLAIN: A contour line is marked 50 m. What does this mean?