Geographer’s Tools
Maps
Globes
Graphs
Organization
• The grid that covers a
globe is made of lines
that run east to west
and north to south.
– Lines of latitude run
east-west
– Lines of longitude run
north-south
Organization
• The equator is an imaginary line that
circles the globe halfway between Earth.
– Lines of latitude measure distances north and
south of the equator. They are also know as
parallels
• The prime meridian is an imaginary line
drawn from the North Pole through
England to the South Pole
– Lines of longitude, also called meridians,
measure distance east and west of the P.M.
Parallels and meridians measure distances in degrees. Those north of the
equator are noted with an N, south with an S. Meridians can go west or east
of the prime meridian and will be noted with a W or E
Hemispheres, Continents, and
Oceans
• The equator divides the
world into two halves,
or hemispheres.
Northern and Southern
• The prime meridian
and the 180 meridian
divide the world into
Eastern and Western
Hemispheres
• 7 Continents
• 4 Oceans
Maps
• Flat representations of all or part of Earth’s
surface.
• There are many ways of presenting our
round earth on flat maps these are called
map projections
– Because the earth is round, all flat maps have
some distortion
– Most common maps projections are
cylindrical, conic, and flat-plane
Cylindrical Maps
• Designed as if a
cylinder has been
wrapped around the
globe
• Meridians parallel
• Landmasses near
poles larger than they
really are
A Mercator map, is a type of cylindrical map projection. It is useful to
navigators because it shows true direction and shape. However landmasses
appear larger than they really are.
Conic Maps
• Designed as if a cone
has been placed over
the globe
• Most accurate along
lines of latitude
• Retains almost true size
and shapes of
landmasses
Most useful for areas with long east-west
dimensions (USA, Russia)
Flat-plane
• Appear to touch the
globe at one point,
such as North or
South Pole.
• Useful for showing
true direction for
airplane pilots and
ship navigators
Flat-plane shows true area size
but distorts shape
Great Circle Route
• A straight line on a
flat map is not the
shortest distance
• Shortest route is
called a great-circle
route
• Pilots and ship
captains use greatcircle routes to help
navigate
The loxodrome is a line of constant heading, and
the great circle, although appearing longer than
the loxodrome, is actually the shortest route
between New York and London.
Geographic Coordinates
• Absolute location
– is shown as (latitude, longitude) or
(33N,118W) which is the location of El
Segundo
• Distance between Lines
– If you divide the circumference of the earth
(approximately 25,000 miles) by 360 degrees,
the distance on the earth's surface for each
one degree of latitude or longitude is just over
69 miles, or 111 km
Even more precise
• Minutes and Seconds
– For precision purposes, degrees of longitude
and latitude have been divided into minutes (')
and seconds ("). There are 60 minutes in
each degree. Each minute is divided into 60
seconds. Seconds can be further divided into
tenths, hundredths, or even thousandths.
– El Segundo – (33.9’25” N,118.4’15” W)
Map Elements
• Cartographers provide
basic map elements to
help us translate the
codes that contain
information on maps
• Almost all maps have
several common
elements
– Distance scale
– Key
– Directional indicator
Distance Scale
• Distance scales helps
us determine real
distance between two
points on a map
• Distances measured
and measurements
used can vary
Keys
• A maps legend, or
key, identifies the
symbols representing
cities, roads, and
other features.
• They can use colors
to represent different
elevations, regions,
and locations
Directional Indicators
• Shows which
directions on a map
are north, south, east,
and west
• A compass rose has
arrows that point to all
four principal
directions
Other Elements
• Inset maps are used
to focus in on a small
part of a larger map
– They can focus in on a
specific area or focus
on an area that is far
away
– The map of the USA
shows both contiguous
and non contiguous
states.
• Contiguous means
connected or bordering
Special-purpose maps
• The two main types of maps we will be
using are political and physical feature
maps
• Other include
– Climate and precipitation maps
– Population and economic maps
– Elevation profile and topographic maps
Climate and Precipitation Maps
Population and Economic Maps
Elevation maps and elevation
profiles help us better understand
the location of physical features
for an area
Elevation is the height above sea
level
Topography - or elevation – is
shown on contour maps
Climate Graphs and Population
Pyramids
• Climate graphs show the average
temperatures and precipitation in a place.
• Population pyramids show the percentage of
males and females by age group in a country’s
population
– Help us understand population trends in countries
– Name comes from pyramid shape
– If not in shape of a pyramid, called age-structure
diagram