Page 17 - Volt Atlas

Latitudes and Longitudes

Latitude and longitude are imaginary lines that are drawn on a map or globe to easily locate places on Earth.
Latitudes are horizontal lines drawn between North Pole and South Pole parallel to the Equator. Longitudes are
vertical lines drawn from east to west of the Prime Meridian. They run from north to south through Greenwich,
England. Both are measured in terms of 360° degrees of a circle. To measure latitudes, the starting point is the
Equator, i.e. 0° latitude. The latitude of the North Pole is 90°N and that of the South Pole is 90°S. Longitude is

measured in degrees either east or west of the Prime Meridian. This means one half of the world is measured in
degrees of east longitude up to 180° and the other half in degrees of west longitude up to 180°. Thus, latitudes
and longitudes are perpendicular to each other.

Latitudes/Parallels Longitudes/Meridians

North Pole 150º W
North Pole
120º W
180º
80º N West 150º E
90º
60º N (–) 120º E

40º N

20º N 60º W

90º
Equator
East
20º S Prime meridian (+)
40º S 30º W

0º 60º E
30º E
Heat Zones Grid: Map reference — Graticule lines

Earth is divided into diff erent heat zones, according The lines of latitude and longitude together form a
to the heat received from the Sun by areas of diff erent grid. Maps are drawn on a grid of these intersecting
latitudes. In all, there are three heat zones on Earth, lines, called graticule. Number of lines in a grid is
namely, the Torrid Zone (23½°N to 23½°S), the used for the reference of a place on a map.
Temperate Zone
North Pole
66½º N
(North and South, NORTH FRIGID ZONE 90º
North Pole
23½° to 66½°), and
Arctic Circle 80º N
23½º N
the Frigid Zone N NORTH T EMPERATE 60º
S 0º 60º N
(North Pole and ZONE
South Pole, 66½° TO R R I D Z ONE Tropic of Cancer 30º 40º N
23½º S West East
to 90°). Great Circle Equator 20º N 60º
Prime meridian 0º 30º
Equator
SOUTH TEMPERATE
Tropic of Capricorn
ZONE
66½º S
20º S
40º S
Antarctic Circle
SOUTH FRIGID ZONE
South Pole
0º
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