1.2 Notes

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Unit 1: Methods of
Geographic Inquiry
A geographer’s basic tools!
Maps and Globes
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Introductory Video
http://videos.howstuffworks.com/hs
w/8402-basics-of-geography-iimaps-and-globes-video.htm
Map Projections
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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?
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Therefore, geographers created maps!
Map Projections
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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 3Dimensional 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
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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
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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
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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
Mercator Map Projection
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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
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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:
A geographer’s best friend!
Maps
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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
Map of Canada
Creating Maps
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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.
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Specifics for topics can include:
• Listing capital cities of provinces/territories
• Describing the amount of rainfall in different parts of the
country
Rainfall Map of the United States of
America
Creating Maps
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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
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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
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On Maps, the colours chosen are very
important! Generally:
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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?
Map of Ontario
Features of a Map
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Title
• Provides a clear description of:
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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
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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
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Date
• The date when the map was produced should
be displayed.
Features of a Map
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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. 
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. 
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 directions
northeast, 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
Click
the mouse button or press the
indicates north only.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. 
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. 
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 specialpurpose 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.
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