Time Zones and Types of Maps Chapter 1 Time Zones and Types of Maps

Time Zones Why 24???? Earth is divided into 24 time zones. It takes about 24 hours for the Earth to rotate on its axis.

World Time Zones Each time zone is 15⁰ wide and corresponds approximately to the lines of longitude. Some time zones have been adjusted to not inconvenience people. Example: if a time zone runs through a big city it may be moved outside the city limits.

Time zones in the U.S. There are 6 time zones in the United States. What time is it right now in Virginia? Arkansas? Utah? Oregon? Alaska? Hawaii?

Types of Maps Chapter 2 Section2

5 Types of Maps Mercator Projection Robinson Projection A cartographer What is a mapmaker called? Mercator Projection Robinson Projection Conic Projection Gnomonic Projection Topographic Map

Mercator Projections Mercator Projection—a map that has parallel lines of latitude AND longitude. It is made by moving the contents of the globe onto a cylinder of paper. This map has distortion near the poles – it makes the land masses near the poles look larger than they really are.

Mercator Maps The Mercator map was developed in 1569 by Gerardus Mercator. Even though the size and distance are distorted at the poles, it shows directions accurately. It was made to help sailors navigate around Earth. It turns the globe into a grid. Still used by navigators today!

Robinson Projection Developed by Arthur H. Robinson. Robinson Projections still has distortion (especially around the edges) but it is minimal compared to a Mercator. Robinson Projections show: Most distances, sizes and shapes accurately

Mercator Vs. Robinson Notice the difference!

Conic Projection Conic Projection—a map projection that is made by moving the contents of the globe onto a cone. The cone touches the map at one particular line of latitude. Little distortion at that line, but more distortion at the top and bottom of this kind of map. These maps are best used to map smaller areas on the globe. Often used to make road maps and weather maps.

Gnomonic Projection Gnomonic Projections – a map that is made by placing a piece of paper on a globe so that it touches a single point. “Great circles” are created and used by navigators to find the shortest distance between two points for long-distance travel in air and sea. This type of map does distort direction and distance between landmasses.

Projection Maps

How maps distort the globe. http://www.youtube.com/watch?v=X4wgFSHZXBg

Topographic Maps Topographic maps—are maps that show surface features (topography) of the Earth. Topographic maps use lines known as contour lines to indicate the elevation of the Earth’s surface on the map.

Topographic Map

Topographic Maps Index Contours Some of the lines on a topographic map will be marked with numbers representing their elevation. This type of contour line is called an Index Contour.

How do you calculate contour interval? Step #1. Locate two index contours. Step #2. Subtract the two numbers. Step #3. Count the number of contour lines between the two numbers. Step #4. Divide the answer from Step 2 by the number of lines counted in Step 3.

Practice calculating contour intervals.

Depression Contour Lines Depression contour lines – some land features, such as volcanic craters and mines, are lower than the surrounding landscape. Depression contour lines have marks on them called hachures.

Map Legends A map legend explains what the symbols on a map represent.

Map Scales When using a map, you need to know how to measure distances by using a map scale. Map Scale – the ratio between distances on a map and actual distances on the surface of Earth.

Graphic Scale Graphic Scale – Consists of lines that represent a certain distance. The line is broken down into sections with each section representing a distance on Earth’s surface.