Unit 1: Methods of Geographic Inquiry A geographer’s basic tools!
Maps and Globes • Introductory Video • http://videos.howstuffworks.com/hsw/8402-basics-of-geography-ii-maps-and-globes-video.htm
Map Projections • Because the earth is a sphere, the only true way to represent the earth is with a ball or sphere. To fully represent the earth, geographers and scientists alike have created the globe. • Imagine yourself as a tourist in New York City. Wouldn’t it be difficult to walk around 45th Street with a globe in your back pocket? • Therefore, geographers created maps!
Map Projections • When features of a globe (or the earth) are transferred to a flat surface, ie: a piece of paper of computer monitor, a map projection is created. • There are several ways to transfer the 3-Dimensional shapes to a 2-Dimensional surface
Map Projections • When a map projection is created, however, there is distortion that occurs • Distortion occurs in the shape and size of the natural features • Because we are transferring the natural features to a 2D surface, we have to stretch or compress some of those natural features.
Types of Map Projections • Interrupted Projection: There are many different types of interrupted projection maps. These types of maps try to depict the continents as accurately as possible by leaving blank space in the less important areas of the map, such as in the oceans.
Types of Map Projections • The most commonly used map is the Mercator Map • developed by Gerardus Mercator, a Flemish mapmaker, in 1569
Map Projection Take the oranges on the right. If we were to draw a triangle on the oranges and then peel the orange. From the peels we would then flatten them as best as possible. What would the triangle look like?
Mercator Map Projection • In the Mercator Map Projection • angles are preserved • distances away from the equator become progressively distorted. • South America (land mass) is actually nine times as big as Greenland • But how does South America compare to Greenland on the Mercator Map?
Mercator Map Projection • The Mercator projection is called Conformal. A projection is conformal if the angles in the original features are preserved. • Over small areas the shapes of objects will be preserved. • A line drawn with constant orientation (e.g. with respect to north) will be straight on a conformal projection (a thumb line). • Parallels and meridians cross each other at right angles (note: not all projections with this appearance are conformal). • Generally, areas near margins have a larger scale than areas near the center (i.e. Greenland in Mercator projection).
Mercator Map Projection • The Mercator map has always been a poor projection for a world map. • Because it was based on a rectangular grid, the average person found it easy to read and found it useful for wall maps, atlas maps, and maps in books. • It became the standard map projection in the mental map of most westerners. • The argument for using the Mercator projection was the "advantage for colonial powers" by making Europe look a lot larger than it actually is on the globe.
Maps • What is a map? • A map is a drawing or image of the earth’s surface drawn on a flat surface. • Maps use symbols and colours to represent the features of an area • A map can be hand drawn or computer drawn
Creating Maps • All maps should be drawn for a purpose, such as: • to provide direction from A to B or to • provide information on a specific topic. • Specifics for topics can include: • Listing capital cities of provinces/territories • Describing the amount of rainfall in different parts of the country
Creating Maps • Great care should be taken when creating a map. • Maps should be drawn neatly and it is best to draw lightly in pencil and then to go over in ink when necessary.
Creating Maps • When placing text on maps, it is best to print the words. • When using colour, it is very important that you chose the correct colour to show different features.
Features of Maps - Colours • On Maps, the colours chosen are very important! Generally: • roads and trails are brown • parks are green • water ways (lakes and rivers) are blue • roads are usually black • highways are usually red or orange • text such as city labels are in black
Features of a Map - Elements • When creating a map, there are some features that must be included on all maps. • What do you see on the following map?
Features of a Map • Title • Provides a clear description of: • the area the map it is representing and • what information is presented (Example: Road Map of Ontario). • tell the reader what the map is used for. • The title should be short and descriptive. • Should be placed in an appropriate location (top and centre). • Should be neat and printed in dark ink.
Features of a Map • Source • The author of a map is called a cartographer. • The person/people/company or organization that created the map should be provided.
Features of a Map • Date • The date when the map was produced should be displayed.
Features of a Map • Legend • The legend provides the map reader with an understanding of the various symbols that are used on the map. • The symbols chosen should accurately reflect the feature that is being represented.
Key Cartographers use a variety of symbols to represent map information. Graphic symbols are easily understood by people around the world. To be sure that the symbols are clear, however, every map contains a key–a list that explains what the symbols stand for. This key shows symbols commonly used on a political map. Reading a Map 2 Click the mouse button or press the Space Bar to display the information.
Boundary Lines On political maps of large areas, boundary lines highlight the borders between different countries, states, or counties. Reading a Map 3 Click the mouse button or press the Space Bar to display the information.
Compass Rose Most maps feature a compass rose, a marker that indicates directions. The four cardinal directions–north, south, east, and west–are usually indicated with arrows or points of a star. The intermediate directionsnortheast, northwest, southeast, southwest–may also be shown, usually with smaller arrows or star points. Sometimes a compass rose may point in only one direction because the other directions can be determined in relation to the given direction. The compass rose on this map indicates north only. Reading a Map 4 Click the mouse button or press the Space Bar to display the information.
Cities Cities are represented by a dot. Sometimes the relative sizes of cities are shown using dots of different sizes. Reading a Map 5 Click the mouse button or press the Space Bar to display the information.
Scale Bar The scale bar shows the relationship between map measurements and actual distances. By laying a ruler along the scale bar, you can calculate how many miles or kilometers are represented per inch or centimeter. Reading a Map 6 Click the mouse button or press the Space Bar to display the information.
Capitals National capitals are often represented by a star within a circle.
Reading a Map Using Scale All maps are drawn to a certain scale. Scale is a consistent, proportional relationship between the measurement shown on the map and the measurement of the earth’s surface. The scale of a map varies with the size of the area shown. Use the scale bar to find actual distances on a map. The scale bar gives the relationship between map measurements and actual distances. Most scale bars are graphic representations, allowing you to use a ruler to calculate actual distances.
Small-Scale Maps A small-scale map, like this political map of Mexico, can show a large area but little detail. Note that the scale bar for this map indicates that about ½ of an inch is equal to 300 miles and a little more than ½ of a centimeter is equal to 300 kilometers.
Large-Scale Maps A large-scale map, like this map of Mexico City, can show a small area on the earth’s surface with a great amount of detail. Study the scale bar. Note that the map measurements correspond to much smaller distances than on a small-scale map.
Types of Maps Maps are prepared for many uses. The use for which a map is intended determines the kinds of information it contains. Learning to recognize a map’s purpose will help you make the best use of its content.
Types of Maps General-Purpose Maps Maps that show a wide range of information about an area are called general-purpose maps. General-purpose maps are typically used for reference, education, and travel. Two common forms of general-purpose maps are physical maps and political maps.
Political Maps A political map shows the boundaries between countries. Smaller internal divisions, such as states or counties, may also be indicated by different symbols. Political maps often show human-made features such as capitals, cities, roads, highways, and railroads.
Types of Maps Special-Purpose Maps Maps that emphasize a single idea or a particular kind of information about an area are called special-purpose maps. There are many kinds of special-purpose maps, each designed to serve a different need. You can learn more about several types of special-purpose maps in the SkillBuilder features in your textbook: relief maps (page 126), climate maps (page 172), population density maps (page 232), vegetation maps (page 432), elevation profiles (page 580), economic activity maps (page 680), and cartograms (page 754).
Types of Maps Special-Purpose Maps Some special-purpose maps–such as economic activity maps and natural resource maps–show the distribution of particular activities, resources, or products in a given area. Colors and symbols represent the location or distribution of activities and resources.
An Economic Activity Map The special-purpose map below shows the distribution of land use and natural resources in Southwest Asia. Geographers use maps like this one to study the distribution of natural resources. Governments and industry leaders use land use maps and natural resource maps to monitor the economic activities of countries and regions.
Common Map Projections Geographic Information Systems Modern technology has changed the way maps are made. Most cartographers use computers with software programs called geographic information systems (GIS). A GIS is designed to accept data from many different sources, including maps, satellite images, and printed text and statistics. The GIS converts the data into a digital code, which arranges it in a database. Cartographers then program the GIS to process the data and produce the maps they need. With GIS, each kind of information on a map is saved as a separate electronic “layer” in the map’s computer files. Because of this modern technology, cartographers are able to make maps–and change them–quickly and easily.