Maps
Three sources of map distortion
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Map scale – most maps are smaller than
the reality they represent. Map scales tell
us how much smaller.
Map projection – this occurs because you
must transform the curved surface of the
earth on a flat plane.
Map type – you can display the same
information on different types of maps.
Map scale – tells us relationship between
distance on map and distance on earth’s
surface

Ratio scale = ratio of map distance to earth
distance.
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1:10,000 means that one inch on the map equals
10,000 inches earth’s surface; one centimeter
represents 10,000 centimeters; or one foot equals
10,000 feet.
Recall a small fraction has a large denominator so
that 1:100,000 is a smaller scale than 1:25,000.
A large-scale map depicts a small area with great
detail.
A small-scale map depicts a larger area with little
detail. Distortion is especially severe here.
A.
B.
C.
D.
Which is
the
largescale
map?
Which map scale shows the most detail?
a. 1:250,000
b. 1:24,000
c. 1:100,000
d. 1:62,500
1.
2.
a.
b.
c.
d.
e.
A map with a large scale usually shows
a large amount of land space
a small amount of land space
physical features only of a land space
the local-global continuum
political boundaries between countries only
Map scale – tells us relationship between
distance on map and distance on earth’s
surface

Ratio scale = ratio of map distance to earth
distance.




1:10,000 means that one inch on the map equals
10,000 inches earth’s surface; one centimeter
represents 10,000 centimeters; or one foot equals
10,000 feet.
Recall a small fraction has a large denominator so
that 1:100,000 is a smaller scale than 1:25,000.
A large-scale map depicts a small area with great
detail.
A small-scale map depicts a larger area with little
detail. Distortion is especially severe here.
location, direction, distance
site and situation
The starting point for a
geographer
(After the map…)
Some Vocab:
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Absolute Direction
Absolute Distance
Absolute Location
Site
Situation
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Relative Direction
Relative Distance
Relative Location
Toponym
Toponym
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Place Name!
Absolute location
mathematical location
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Clemmons is:
36o 01’ 17.30” N (longitude)
80o 22’ 55.15” W (latitude)
700 building
36o 03’ 48.84” N
80o 22’ 55.15“ W
Site
internal physical attributes


(includes absolute location, but includes
the physical setting; especially in urban
geography)
Clemmons is bordered on the West by the
Yadkin River
Relative location
regional position relative to other places
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(general spatial interconnection and
interdependence)
Clemmons is in the northwest piedmont
section of Forsyth County
Davidson County is to the south
Davie County (Advance) is to the west
Winston-Salem is 10 miles to the east
Exit off I-40 & Hwy 421
Situation
external location attributes
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(external relations, a type of relation location that refers
to items of significance, especially in urban geography)
Suburb of Winston-Salem, a bedroom
community for persons working in the
medical, bio technical/medical and
aeronautical businesses in the Triad
I-40 and US 421, major transportation
Absolute direction
cardinal points N-S-E-W

Clemmons is southwest of Winston-Salem.
Relative direction
culturally based, not necessarily an accurate
cardinal point


Clemmons is in the “South”.
Clemmons is …
Absolute distance
mathematical space between 2 points

Clemmons is 10 miles (16km) from
Winston-Salem.
Relative distance
meaningful space measurement


Clemmons is about 15 minutes from
Winston-Salem.
Clemmons is one hour from Mt. Airy.
“City of
2
Million”
article
Use the terms…
1. Describe the absolute location, absolute
direction and absolute distance of a place
of your choice.
2. Describe the relative location, relative
direction and relative distance of the same
place.
3. Describe the site.
4. Describe the situation.
Which of the following is not a measure of relative
distance?
a. 2,339 cm
b. 35 seconds
c. $2.50 cab ride
d. 216 footsteps
e. 15 minutes
1.
2.
a.
b.
c.
d.
e.
Relative location is an important geographic concept
mainly because it
locates places according to longitude and latitude
defines a place in terms of how central or isolated it is
to other places
defines patterns of natural environment
helps cartographers to develop more accurate maps
illustrates how local, regional and global factors interact
within the local-global continuum
1.
Who demonstrated the Earth was round
using maps?
a. Ptolemy
c. Eratosthenes
2.
b. Aristotle
d. Sauer
Who coined the word geography?
a. Ptolemy
c. Eratosthenes
b. Aristotle
d. Sauer
Evolution of Mapmaking
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Babylonians – 2300 BC earliest surviving
maps written on clay tablets.
Aristotle – 384-322 BC demonstrated earth
was spherical through maps.
Eratosthenes – 276-194 BC first person to use
the word geography. Also the first person to
correctly divide earth into 5 climatic regions.
Ptolemy – 100-170 AD Guide to Geography
Age of Exploration – by the 17th century,
most continents and oceans were accurately
displayed.
Contemporary Mapping

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GIS (geographic information systems)
GPS (global positioning system)
Remote Sensing Satellites
a. Remote Sensing
c. GIS
1.
2.
b. GPS
d. DTM
Layers of geographical information that
can be selected or deselected when
viewing a map
Can immediately scan the Earth’s surface
to determine changes in geography
GIS Layers
Use of GIS in Emergencies
Remote Sensing

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The acquisition of data about Earth’s surface remotely
such as from an airplane or satellite orbiting the planet.
Primarily environmental mapping – vegetation, surface
cover, winter ice cover, deforestation
Satellite images of the north-east coast of Japan before
(left) and after the earthquake and tsunami. Water is
black or dark blue and the thin green line in the 'after'
image indicates the shoreline. Photograph: Nasa

http://www.nytimes.com/interactive/2011/03/13/world/asia/satellite-photos-japan-before-and-after-tsunami.html?_r=0

http://eijournal.com/2011/disaster-response-in-japan-2
Map Grid
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Latitude /Longitude
Tropics
Equator
Prime Meridian /International Date Line
Gain a Day
Skip a Day
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Immediately to the left of the International Date Line, the date is always one day ahead
of the date immediately to the right of the International Date Line. On the time and date
codes shown below, note that Tonga and Samoa have the exact same time, but are
actually one day apart, as Samoa is in the Western Hemisphere (to the east of the dateline)
and Tonga is in the Eastern Hemisphere.
In summary, travel west across the International Date Line and you will gain a day, travel
east across it and you will lose a day.
All Maps should Have
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Cartographer
Title
Scale
Key
How to Lie with maps
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A map is a generalization or representation of
the real world.
Cartography – the science of mapmaking.
All maps lie flat and all maps lie. They
contain distortions. You cannot represent the
three-dimensional earth on a flat surface
without distorting reality.
Any useful map is selective in what is put in
and left out. Example: road or subway map.
Is this a correct map of London?
Is this a correct map of London?
Which map
would be useful
to tour
London?
Three sources of map distortion



Map scale – most maps are smaller than
the reality they represent. Map scales tell
us how much smaller.
Map projection – this occurs because you
must transform the curved surface of the
earth on a flat plane.
Map type – you can display the same
information on different types of maps.
Map Type – you can display the
same information on different maps

Types of maps:

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
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Dot – each dot represents some frequency
Isoline – connects points of equal value
Choropleth – puts features into classes and then
maps classes for each region
Cartogram – adjusts the size of the country
corresponds to the magnitude of the mapped
feature
Proportional symbol – size of the symbol
corresponds to the magnitude of the mapped
feature
Dot – each dot represents some
frequency
Chart
Map
Students applauding at Lecture
Key:
desk
incidents of applauding
Scale 1:9
Cartographer: D. Troxell
Isoline – connects points of equal
value
Choropleth – puts features into
classes and then maps classes for
each region
Proportional symbol – size of the
symbol corresponds to the
magnitude of the mapped feature
Cartogram – adjusts the size of the
country corresponds to the
magnitude of the mapped feature
http://www.worldmapper.org/
Other Thematic Maps- spatial
distribution of one or more specific
themes
What kind of map is this?
What kind of map is this?
What kind of map is this?
What kind of map is this?
Other types of visual images:

Mental map = map of an area in your mind
A
B
D
C
Proportional Symbol?
E
A
B
D
C
Dot Map?
E
A
B
D
C
Isoline?
E
A
B
D
C
Cartogram?
E
A
B
D
C
Choropleth?
E
A
B
D
C
Good for showing
points of equal value?
E
FRQ Practice – NO Notes
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Define the following
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Absolute Location
Relative Location
Absolute Distance
Relative Distance
Toponym
Explain Clemmons using the following
terms Absolute Location

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Relative Location
Absolute Distance
Relative Distance
Toponym