2.8 : Map Projections - II

Map Projection II

Earth is round, but maps are flat. A map projection is a method used to show Earth’s surface on a flat surface. Because flattening a sphere always causes distortion, some parts of the map may look stretched, squished, or misaligned. Different projections are used for different purposes.

Maps take the three-dimensional shape of the Earth and turn it into a two-dimensional image, which can lead to distortions. Different projections address this issue, each with its advantages and trade-offs:

Science and Engineering Practices (SEP): Analyzing and Interpreting Data

Maps provide valuable information but can look different depending on how they are made. You can explore how projections affect distance, shape, and area by comparing maps.

Activity Ideas:

• Use an online map to measure the distance between two cities and compare it to a paper map. Do the measurements match?
• Look at old maps and compare them to modern satellite images. How have mapping techniques improved?
• Track your movements using a mapping app for a day. Then, compare your recorded path to a physical map for accuracy.

As you explore, ask these questions:

• Why do some maps show different distances between locations than others?
• How do satellite images help improve the accuracy of maps?
• How can tracking real-world locations help us understand how maps work?

Crosscutting Concept (CCC): Patterns

Since Earth is a sphere, any attempt to flatten it creates predictable distortions in shape, size, distance, and direction. Have you ever noticed that airline routes look curved on a map? This happens because maps flatten the round Earth, changing how things appear.

Learning about the reasons why different map projections are used for different things can help you understand these patterns.

Recognizing distortion patterns helps you understand why maps look different and why geographers use various projections for specific tasks. For example:

• Navigators use Mercator maps because they preserve straight-line courses.
• Climatologists use Equal-Area projections to compare land sizes accurately.
• Geologists use different projections to study plate tectonics and land formations.

Different maps show patterns, helping us analyze and interpret information. Maps shape how we view the world. By carefully analyzing them, we can learn more about geography, navigation, and climate. As technology improves, maps become even more accurate, helping people explore and understand the world in new ways.