Question

Which type of map shows changes in elevation at Earth's surface? A) conic C) Robinson B) topographic D) Mercator

Short answer

B) topographic

Step-by-step solution

Understanding Map Types

Different map types serve various purposes based on the information they present. A conic map projects the Earth on a cone and is often used for mapping regions with a larger east-west spread. A Robinson map is an attempt to portray the entirety of the Earth in a visually appealing way, balancing size, shape, and area. A Mercator map is a cylindrical projection that represents angles correctly, useful for marine navigation.

Definition of Topographic Maps

Topographic maps are specifically designed to show elevation and landforms. They use contour lines to represent changes in elevation and accurately depict the Earth's surface including valleys, hills, and mountains.

Identifying Correct Option

Given the map types explained and knowing that elevation changes are depicted through contour lines, the map type that fulfills this description is the topographic map.

Key concepts

Contour Lines

Contour lines are a fundamental feature of topographic maps. They are lines drawn to connect points that are at the same elevation above sea level. Think of them as the outlines of layers on a staircase that show how steep or gentle a slope is. These lines never intersect with each other, as each represents a distinct elevation.

On a topographic map, contour lines that are close together illustrate a steep slope. Conversely, lines that are far apart indicate a gentle slope or flat terrain. The idea is to give a clear visual sense of the landscape’s shape.

• Each line has a number called an elevation marker that tells you the height above sea level.
• Index contours are the thicker contour lines that are labeled with elevation.

By using contour lines, topographic maps allow us to understand terrain without seeing it directly.

Elevation Changes

Elevation changes on a map show how high or low different areas are compared to sea level. This is crucial when planning activities like hiking or construction, where understanding the steepness of terrain is vital. When you see contour lines on a topographic map with varying distances, it highlights how elevation changes across a region.

Some key aspects of elevation changes include:

• **Relief:** The difference between the highest and lowest points in a region.
• **Gradient:** The rate at which elevation changes, calculated as the steepness.
• Feeling the shape of the land by observing the pattern of contour lines is a skill that enhances map reading.

Grasping these concepts helps users comprehend types and extents of terrain changes, making topographic maps incredibly useful for environmental assessments and outdoor adventures.

Map Projections

Map projections are methods of representing the 3D surface of the Earth on a 2D surface, like a map. Since Earth is a sphere, every projection distorts some aspect of the surface, be it shape, area, or direction. Understanding the different types of map projections helps in choosing the right one for specific purposes.

Some common projections include:

• **Mercator:** Preserves angles and shapes for navigation, distorting size especially near the poles.
• **Conic:** Useful for regional maps with an emphasis on preserving area and shape along the latitude lines.
• **Robinson:** Strikes a balance to show the whole world, often used in educational settings despite minor distortions.

Each map projection has advantages and limitations. In the context of topographic maps, the focus is on accurately depicting elevation without compromising too much on shape or distance.