MAPPING THE WORLD

Maps

Maps are fundamental to the discipline of geography and have been used
by humans since before 6,000 B.C. Today’s maps are much more sophisticated,
complex, and precise, and are used by many people who employ GPS mapping
systems in their vehicles. This technology allows motorists to navigate from placeto-
place with relative ease, but the process by which these digital and other maps
are created is exceptionally complex.
Essentially, a map, which is a flat presentation of a place on Earth, is actually
depicting a curved surface. The Earth, which looks like a sphere, is technically an
oblate spheroid, which means that the “middle” of the Earth, around the equator,
is slightly wider, and the north/south pole axis is slightly shorter, than a perfect
sphere. When any curved surface is depicted on a flat surface, that process is
known as projection, and many types of map projections exist. A fundamental
characteristic of all maps is they involves projections, and all projections have
some sort of distortion inherent in them. The size, shape, distance, and direction of
objects are distorted to various degrees on maps. The reason this distortion occurs
can be visualized by simply imagining peeling an orange, and trying to flatten the

peel on a table. If you drew the continents on that orange before peeling it, the
continents would most certainly be distorted when you try to flatten the peel on
the table. This analogy does not precisely describe how projections are created; the
process is much more involved. However, the underlying principle still applies. An
example of distortion is shown on the map of the globe below (Figure 1.2). Note,
for example, in this Mercator projection that Greenland appears to be larger than
South America, although it is, in fact, much smaller.
Besides projections, another important characteristic of maps is the scale. The
scale of a map is a ratio of the length or distance on the map versus the length or
distance on the Earth or ground (actual). The amount of detail shown on a map
will vary based on the scale. For example, a map with a scale of 1:100,000 (which
means 1 in/cm on the map equals 1,000,000 in/cm on the ground) would show
much less detail than a map at a scale of 1:10,000 (Figure 1.3). Besides showing
scale as a ratio, it can also be presented as a bar graph or as a verbal statement.
Scale can also mean the spatial extent of some kind of phenomena. For example,
one could examine migration at the global, national, state, or local scale. By either
definition, however, each refers to the level of detail about the place that the
geographer is researching. Examining the world from different scales enables
different patterns and connections to emerge.

WHERE IN THE WORLD AM I?

One of the most important pieces of information that maps provide is location.
Knowing precisely where a place is in the world is fundamental to geography.

While one can define a location simply by using a street address, not all places on
Earth have such an address. Therefore, one of the basic ways to pinpoint a location
on the Earth is using the geographic grid. The geographic grid is comprised of
meridians and parallels, which are imaginary lines and arcs crisscrossing the
Earth’s surface. Meridians are half circles that connect the north and south poles,
and longitude refers to the numbering system for meridians. Parallels are
circles that encompass the Earth and are parallel to the equator, and the numbering
system for these circles is known as latitude (Figure 1.4). Where meridians and
parallels intersect at precise locations (points) on the Earth on the geographic grid,
a location can be known by its latitude and longitude.

A few meridians on Earth are of particular importance, one being the Prime
Meridian located at 0o longitude, which passes through Greenwich, England. The
other important meridian, called the International Date Line, follows roughly
along 180 o longitude, and this meridian is on the opposite side of the world from
the Prime Meridian (Figure 1.5). When a traveler crosses the International Date
Line, the day of the week instantaneously changes. When moving westward, the
day moves forward, and when traveling eastward, the date jumps backward one
day. Fortunately, the International Date Line is in the middle of the Pacific Ocean,
so disruptions to the daily calendar are minimal for most people in the world.
Moreover, the International Date Line does not precisely follow the 180 o longitude
line, and this accommodation allows countries and territories consisting of islands
that straddle 180 o longitude to share the same calendar date.

HOW DO I DESCRIBE WHERE I AM?
Defining a location by using the geographic grid is only part of the process of
describing a place. Geographers are primarily concerned with two ways of describing
a place: site and situation. Site refers to the physical characteristics, such as the
topography, vegetative cover, climatic conditions, and the like. Situation, on the
other hand, refers to the area surrounding the place, and is sometimes referred to
as relative location. In other words, where is this place relative to other places, and
how is it connected to its surroundings via transportation networks? New Orleans
provides an excellent example of site versus situation. The site of New Orleans is
not ideal for a city, as it lies below sea level and is prone to flooding. However, the
situation of New Orleans is much better in that New Orleans is connected to large
portion of the Mississippi River’s network of navigable waterways while also being
close to the Gulf of Mexico and convenient to coastal traffic. Hence, the situation of
New Orleans is why the city has not long since been abandoned, despite catastrophic
flooding such as during Hurricane Katrina in 2005. As we examine various places
around the world, both site and situation are key considerations in determining
the “why” of where a place is located.