Goals of Cartography and GI: Representation and Communication - A Primer of GIS: Fundamental Geographic and Cartographic Concepts - page 23

Summary

Geographic information and maps are ways of representing what people see
and observe. Things and events should be distinguished. Things refer to
static representations of something in the world; events refer to dynamic
changes. Because of the complexity of the world, even small aspects of it,
and the challenges of representing the world, a number of choices are
brought together in geographic representations and cartographic represen-
tations. Because of the large number of choices, cultures, fields of science,
and professions rely on conventions and frameworks. Conventions are often
unstated guidelines for representation. Frameworks are rules and procedures
for dealing with the complexity of choices. Geographic information and
maps have a great deal of power as a result of making portions of the world
understandable. The quality and reliability of geographic information and
maps depends on how well they fit the purpose, or “fitness for use.”

In-Depth Globes

For many people globes seem to be ideal cartographic representations of the
earth's geography. They are certainly attractive, but for a number of reasons
they are limited in their use and suit-
ability for most maps and geographic
information. They remain, however,
the best reference for understanding
the earth's three-dimensional shape
and for conceptualizing latitude and
longitude.

Making a Globe
A globe ends up round, but it is printed
on a f lat piece of paper just like any
other map. The map is divided, and
later cut, into what is called a “gore.”
When the paper is glued to the round base, these strips fit together, resulting in
an uninterrupted sphere. This technique has been used for several hundred
years.

Globes indicate lines of latitude and longitude, also
called respectively parallels and meridians.

Reading a Globe
Locations on a globe can be found by latitude and longitude. Latitude is a
degree measure used to indicate the relative distance from the equator. Longi-
tude is another degree measure that has a fixed origin, nowadays the Green-
wich meridian, running through Greenwich, England, just outside London.
Meridians run from pole to pole; parallels run from east to west at a constant
latitude.