Geography For Dummies. Jerry T. Mitchell
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(© John Wiley & Sons Inc.)
FIGURE 4-8: The Peters projection.
This size issue is key for advocates of the Peters projection, saying that it renders an important measure of cartographic justice for tropical less-developed regions. They claim that by inflating the size of high-latitude regions relative to the tropics, the Mercator and some other projections present a Europe-centered view of the world that denigrates places in Asia, Africa, and South America. Proponents point out that the Peters projection is an equal area projection that shows tropical regions in their true size relative to, say, Europe and North America. As a result of such advocacy, several agencies with strong interests in these places have adopted the Peters projection as their official depiction of the world.
But is this projection really any better than the others? When you look at the facts of the matter, three things are obvious:
First, the Peters projection terribly distorts shape (especially near the Poles and Equator) and distance.
Second, there is a perfectly good alternative to the Peters that is an equal area map and depicts shape of tropical regions with considerable accuracy — the Goode’s projection.
Third, there is nothing new about The New Cartography. The Peters projection is a knock-off of a projection that was developed by James Gall in 1885. As result, it is usually called the Gall-Peters projection nowadays.
So, is there one perfect world projection that lies flat without lying? No. Is there one perfect projection for all situations? Again, no. Representing Earth cartographically can be as crazy as all the physical and human features contained within it. Do your best!
Chapter 5
Telling a Spatial Story
IN THIS CHAPTER
Knowing what a map is showing
Measuring distance and size
Taking a look at graphics
Using symbols to depict reality
Finding ways to gather information
Harnessing new technologies
I collect old maps, particularly ones of places I once lived like Maryland, Pennsylvania, California, and so on. So, I’m a geek, I guess. Before you think of yourself as being too cool, remember that no one made you pick up this book. So, I guess I’m not the only geek out there!
Of those maps, one is my most prized and until I found a copy in a dusty shop in Savannah, Georgia, I had not seen one like it. It’s a map of major world rivers and mountains published in Gray’s Atlas in 1874. But it isn’t laid out like a traditional map. Each major river is positioned side by side from longest to shortest, and each major mountain is in a row by continent from shortest to tallest. I find the comparisons and different layout fascinating and spatially pleasing for some reason only geeks like you and me can understand. A neat added feature in one corner is a smudged fingerprint. I love the idea of someone like me — or you — exploring physical Earth space with this map nearly 150 years ago.
Over the years, and much to my relief, I have met numerous other geography geeks (geography teachers and students among them) who, however meekly, admitted to similar map affections. Indeed, such behavior turns out to be perfectly normal for people who, whether or not they know it, have a yearning for geography. No doubt, that is because the map is the most basic geographical tool.
Complementing the previous chapters on Earth’s grid and the properties of projections, this chapter focuses on ways in which maps communicate information and how some of that information is obtained. Basically, this chapter is about map reading and map information for the budding geographer. Therefore, if you are, in fact, one of those people who can stare at maps for hours, then you can probably skip this chapter. But if maps confuse you or seem overwhelming, or if you have never been taught the fundamentals of maps and map reading, then this chapter is for you. While you probably won’t master all there is to know, you can familiarize yourself with enough fundamentals so that you get the message of maps.
Why We Need Tal(l) Dogs
The basic function of maps is to show how particular phenomena are distributed over all or part of the world. Cartographers (mapmakers) communicate these and other kinds of information in part by incorporating into their maps a standard set of elements whose purpose is to help the map-reader get the message.
An easy way to remember these elements is with the acronym TALDOGS:
Title: The title conveys the subject of the map and is the first thing a map-reader should look for. Ideally, its wording is simple and accurate. If the title confuses you, then that is probably more of a comment on the cartographer’s communication skills than your intelligence quotient.
Author: Knowing who made the map might say something about the map’s credibility. Are you more likely to trust a map made by the National Geographic Society or one you found online created by [email protected]
(that’s right, we just made that email address up, so no writing in, Joe!)?
Legend: Maps commonly convey information with the aid of symbols whose meanings may be uncertain. Thus, the cartographer always provides a legend (or key) that contains and defines the symbols found on the map.
Date: Every map in print is out of date once printed — the world changes that fast. Newer digital mapping technologies are making this a problem of the past as we can update spatial data more quickly. However, knowing when data is collected can help us in making spatial and temporal comparisons.
Orientation: Orientation is the alignment of the map with respect to cardinal directions: which way are north, south, east and west? The standard rule is that north is towards the top of the map, but not every layperson knows the rule and not every map follows it. Accordingly, many maps include a direction indicator, minimally a north-pointing arrow.
Grid: Many maps contain a couple of labeled grid lines of latitude and longitude (see Chapter 3) in order to convey the global context of the mapped area. If the cartographer has reason to believe that the map reader is intimately familiar with the mapped area, or if previous maps have indicated the global context of the mapped area, then grid lines may be omitted.
Scale: Scale (described more fully in the following section) provides information about the actual size of the area shown on the map. Typically, this is achieved with a small ruler-like entry on a map that equates distance in miles and/or kilometers with measurement in inches and/or centimeters.