Mapping Concepts & Features

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Francisci
WG.1
Latitude: Location north or
south of the Equator,
measured by imaginary
lines called parallels
numbered in degrees north
or south.
• Parallel to equator.
• Lat is flat!
Equator: Zero degrees
latitude, divides the earth
into northern and southern
hemispheres.
Longitude: Location east or
west of the Prime Meridian,
measured by imaginary lines
called meridians numbered
in degrees east or west.
• Vertical Lines
• Longitude is long!
Prime Meridian: Zero degrees
longitude also known as the
Greenwich Meridian (1884 –
Greenwich Observatory near
London. Created a universal
day and 24 hour clock).
Absolute Location: Relationship
between distance on a map and
the actual distance on
the Earth (expressed
mathematically).
• Exact place, or location where
someone, or something is on
the Earth.
Coordinates: The intersection of
latitude and longitude lines,
which identify the exact
location of a place.
 Memphis, Tennessee is at
35° latitude and 90° west
longitude.
 My house is at 1920 First
Avenue.
Relative Location: Place or
position on the globe that is
expressed in terms of one or
more known locations.
Examples:
• The state of Kentucky is
north of Tennessee.
• The pool is a half mile north
of the high school.
• The library is between Smith
and Jones Hall.
Relative location means to locate a place in relation to
another place whereas absolute location is locating a
place using a coordinate system.
• Example: St. Louis, Missouri
• Absolute Location: 38°43' North 90°14' West.
• Relative Location: Along the
Mississippi River southeast
of St. Charles.
Scale: Indicates the relationship between the distances
on the map and the actual distances on the Earth.
• Will show what a measurement on a map is equal to in
real life.
Directional Indicator: A
device drawn on maps to
show direction.
Compass Rose :
 Flower like design used
to show directions
usually showing 32
points on the compass.
 Shows orientation
(object or person’s
location relative to true
north).
Cardinal Directions: The
basic directions on earth:
north, south, east or west
(found on a Compass
Rose).
Intermediate Directions:
Directions that fall
between cardinal
directions: northwest,
southwest, southeast and
northeast (found on a
Compass Rose).
Map Projection: A way of drawing the round Earth on a flat surface.
Map Distortion: Features such as size, shape, distance, or scale that
can be measured accurately on Earth, but once projected on a
flat surface, not all of these qualities are accurately represented.
Why is a flat map of the Earth always distorted?
A: It is difficult to show the surface of a round Earth on a flat map.
Mercator Projection:
• Grid projection
that is useful for
ship navigation.
• Shows land
shapes fairly
accurately.
• Size and distance
not accurate.
Polar Projection:
• Circular projection best
used for mapping
hemispheres as well as
plane/airline navigation.
• Extremely distorted.
Robinson Projection:
Fish blow shaped projection best used for data
representation; shows size and shape with less
distortion.
• Best for general purposes.
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