Cartography

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"Mapmaker" redirects here. For other uses, see Mapmaker (disambiguation).
The oldest original cartographic artifact in the Library of Congress: a nautical chart of the Mediterranean Sea. Second quarter of the fourteenth century.

Cartography (in Greek chartis = map and graphein = write) is the study and practice of making geographical maps. Combining science, aesthetics, and technique, cartography builds on the premise that reality can be modeled in ways that communicate spatial information effectively.

The fundamental problems of cartography are to:[citation needed]

Contents

[edit] History

Main articles: History of cartography and List of cartographers
Copy (1475) of St. Isidore's TO map of the world.

The earliest known map is a matter of some debate, both because the definition of "map" is not sharp and because some artifacts speculated to be maps might actually be something else. A wall painting, which may depict the ancient Anatolian city of Çatalhöyük (previously known as Catal Huyuk or Çatal Hüyük), has been dated to the late 7th millennium BCE.[1][2] Other known maps of the ancient world include the Minoan “House of the Admiral” wall painting from c. 1600 BCE, showing a seaside community in an oblique perspective and an engraved map of the holy Babylonian city of Nippur, from the Kassite period (14th – 12th centuries BCE).[3]

The ancient Greeks and Romans created maps, beginning at latest with Anaximander in the 6th century BC.[4] In the 2nd century AD, Ptolemy produced his treatise on cartography, Geographia. [5] This contained Ptolemy's world map - the world then known to Western society (Ecumene). As early as the 700s, Arab scholars were translating the works of the Greek geographers into Arabic.[citation needed]

In ancient China, geographical literature spans back to the 5th century BC. The oldest extant Chinese maps come from the State of Qin, dated back to the 4th century BC, during the Warring States Period. In the book of the Xin Yi Xiang Fa Yao, published in 1092 by the Chinese scientist Su Song, a star map on the equidistant cylindrical projection.[6][7] Although this method of charting seems to have existed in China even prior to this publication and scientist, the greatest significance of the star maps by Su Song, is that they represent the oldest existent star maps in printed form.

Early forms of cartography of India included legendary paintings; maps of locations described in Indian epic poetry, for example, the Ramayana.[8] 327</ref> Indian cartographic traditions also covered the locations of the Pole star, and other constellations of use.[8] These charts may have been in use by the beginning of the Common Era for purposes of navigation.[8]

Mappa mundi is the general term used to describe Medieval European maps of the world. Approximately 1,100 mappae mundi are known to have survived from the Middle Ages. Of these, some 900 are found illustrating manuscripts and the remainder exist as stand-alone documents (Woodward, p. 286).

The Tabula Rogeriana, drawn by Muhammad al-Idrisi for Roger II of Sicily in 1154.

The Arab geographer, Muhammad al-Idrisi, produced his medieval atlas Tabula Rogeriana in 1154. He incorporated the knowledge of Africa, the Indian Ocean and the Far East, gathered by Arab merchants and explorers with the information inherited from the classical geographers to create the most accurate map of the world up until his time. It remained the most accurate world map for the next three centuries.[9]

In the Age of Exploration, from the 15th century to the 17th century, European cartographers both copied earlier maps (some of which had been passed down for centuries) and drew their own based on explorers' observations and new surveying techniques. The invention of the magnetic compass, telescope and sextant enabled increasing accuracy. In 1492, Martin Behaim, a German cartographer, made the oldest extant globe of the Earth.[10]

Johannes Werner refined and promoted the Werner map projection. In 1507, Martin Waldseemüller produced a globular world map and a large 12-panel world wall map (Universalis Cosmographia) bearing the first use of the name "America". Portuguese cartographer, Diego Ribero, was author of the first known planisphere with a graduated Equator (1527). Italian cartogapher Battista Agnese produced at least 71 manuscript atlases of sea charts.

Due to the sheer physical difficulties inherent in cartography, map-makers frequently lifted material from earlier works without giving credit to the original cartographer. For example, one of the most famous early maps of North America is unofficially known as the "Beaver Map", published in 1715 by Herman Moll. This map is an exact reproduction of a 1698 work by Nicolas de Fer. De Fer in turn had copied images that were first printed in books by Louis Hennepin, published in 1697, and François Du Creux, in 1664. By the 1700s, map-makers started to give credit to the original engraver by printing the phrase "After [the original cartographer]" on the work.[11]

[edit] Technological changes

A pre-Mercator nautical chart of 1571, from Portuguese cartographer Fernão Vaz Dourado (c. 1520-c.1580). It belongs to the so-called plane chart model, where observed latitudes and magnetic directions are plotted directly into the plane, with a constant scale, as if the Earth were plane (Portuguese National Archives of Torre do Tombo, Lisbon).

In cartography, technology has continually changed in order to meet the demands of new generations of mapmakers and map users. The first maps were manually constructed with brushes and parchment; therefore, varied in quality and were limited in distribution. The advent of magnetic devices, such as the compass and much later, magnetic storage devices, allowed for the creation of far more accurate maps and the ability to store and manipulate them digitally.

Advances in mechanical devices such as the printing press, quadrant and vernier, allowed for the mass production of maps and the ability to make accurate reproductions from more accurate data. Optical technology, such as the telescope, sextant and other devices that use telescopes, allowed for accurate surveying of land and the ability of mapmakers and navigators to find their latitude by measuring angles to the North Star at night or the sun at noon.

Advances in photochemical technology, such as the lithographic and photochemical processes, have allowed for the creation of maps that have fine details, do not distort in shape and resist moisture and wear. This also eliminated the need for engraving, which further shortened the time it takes to make and reproduce maps.

Advances in electronic technology in the 20th century ushered in another revolution in cartography. Ready availability of computers and peripherals such as monitors, plotters, printers, scanners (remote and document) and analytic stereo plotters, along with computer programs for visualization, image processing, spatial analysis, and database management, have democratized and greatly expanded the making of maps. The ability to superimpose spatially located variables onto existing maps created new uses for maps and new industries to explore and exploit these potentials. See also: digital raster graphic.

These days most commercial-quality maps are made using software that falls into one of three main types: CAD, GIS and specialized illustration software. Spatial information can be stored in a database, from which it can be extracted on demand. These tools lead to increasingly dynamic, interactive maps that can be manipulated digitally.

[edit] Map types

[edit] General vs thematic cartography

Small section of an orienteering map.
Topographic map of Easter Island.

In understanding basic maps, the field of cartography can be divided into two general categories: general cartography and thematic cartography. General cartography involves those maps that are constructed for a general audience and thus contain a variety of features. General maps exhibit many reference and location systems and often are produced in a series. For example, the 1:24,000 scale topographic maps of the United States Geological Survey (USGS) are a standard as compared to the 1:50,000 scale Canadian maps. The government of the UK produces the classic 1:63,360 (1 inch to 1 mile) "Ordnance Survey" maps of the entire UK and with a range of correlated larger- and smaller-scale maps of great detail.

Thematic cartography involves maps of specific geographic themes, oriented toward specific audiences. A couple of examples might be a dot map showing corn production in Indiana or a shaded area map of Ohio counties, divided into numerical choropleth classes. As the volume of geographic data has exploded over the last century, thematic cartography has become increasingly useful and necessary to interpret spatial, cultural and social data.

An orienteering map combines both general and thematic cartography, designed for a very specific user community. The most prominent thematic element is shading, that indicates degrees of difficulty of travel due to vegetation. The vegetation itself is not identified, merely classified by the difficulty ("fight") that it presents.

[edit] Topographic vs topological

A topographic map is primarily concerned with the topographic description of a place, including (especially in the 20th century) the use of contour lines showing elevation. Terrain or relief can be shown in a variety of ways (see Cartographic relief depiction).

A topological map is a very general type of map, the kind you might sketch on a napkin. It often disregards scale and detail in the interest of clarity of communicating specific route or relational information. Beck's London Underground map is an iconic example. Though the most widely used map of "The Tube," it preserves little of reality. It varies scale constantly and abruptly, it straightens curved tracks, and it contorts directions haphazardly. The only traits the map preserves are the order of the stations and crossings along the tracks and whether a station or crossing is north or south of the River Thames. Yet those are all a typical passenger wishes to know, so the map fulfills its purpose.[12]

[edit] Map design

See also: Map projection
Illustrated map.

Arthur H. Robinson, an American cartographer influential in thematic cartography, stated that a map not properly designed "will be a cartographic failure." He also claimed, when considering all aspects of cartography, that "map design is perhaps the most complex."[13] Robinson codified the mapmaker's understanding that a map must be designed foremost with consideration to the audience and its needs.

From the very beginning of mapmaking, maps "have been made for some particular purpose or set of purposes".[14] The intent of the map should be illustrated in a manner in which the percipient acknowledges its purpose in a timely fashion. The term percipient refers to the person receiving information and was coined by Robinson.[15] The principle of figure-ground refers to this notion of engaging the user by presenting a clear presentation, leaving no confusion concerning the purpose of the map. This will enhance the user’s experience and keep his attention. If the user is unable to identify what is being demonstrated in a reasonable fashion, the map may be regarded as useless.

Making a meaningful map is the ultimate goal. Alan MacEachren explains that a well designed map "is convincing because it implies authenticity" (1994, pp. 9). An interesting map will no doubt engage a reader. Information richness or a map that is multivariate shows relationships within the map. Showing several variables allows comparison, which adds to the meaningfulness of the map. This also generates hypothesis and stimulates ideas and perhaps further research. In order to convey the message of the map, the creator must design it in a manner which will aid the reader in the overall understanding of its purpose. The title of a map may provide the "needed link" necessary for communicating that message, but the overall design of the map fosters the manner in which the reader interprets it (Monmonier, 1993, pp. 93).

In the 21st century it is possible to find a map of virtually anything from the inner workings of the human body to the virtual worlds of cyberspace. Therefore there are now a huge variety of different styles and types of map - for example, one area which has evolved a specific and recognisable variation are those used by public transport organisations to guide passengers, namely urban rail and metro maps, many of which are loosely based on 45 degree angles as originally perfected by Harry Beck and George Dow.

[edit] Layout

[edit] Legend

The legend of a map defines the symbols that are used. Not all symbols should be included in the legend; Symbols that are intuitive do not need to be defined in the legend. Any symbols that are not central to the map's theme can also be omitted from the legend. The appearance of a legend should be simple. A subtle border and definition next to each symbol in the legend make it useful and aesthetically pleasing. The symbols inside the legend should be identical to the corresponding symbols on the map in size, shape, color, etc. The position of a legend depends largely on the open space available in the map. It should be centered in an area of open space. It should be large enough to be easily legible but small enough to keep from drawing too much attention away from the map.[16]

When designing a legend for a map it should be approached the same way that you would approach designing a map or any other kind of graphical representation. The legend is a graphical representation of information. The only difference is that it is related to the information on the map it is connected to. Therefore it is important to remember the layout design concepts such as harmony, visual balance, clarity, visual logic, logical groupings, and unambiguous references to create a legend that is effective in relationship to the map. Creating a well laid out legend will only enhance the over all Gestalt of the maps visual appearance. Often times a well designed map can appear bad because of a poorly designed legend. It is important for map makers to keep an open and creative mind when designing the legend, and to make sure that it connects well to the map.[17]

[edit] Scale Bar

Maps are smaller than the part of the earth's surface they depict. Cartographic scale expresses this relationship, traditionally in one of three ways. A verbal scale statement expresses the amount of distance on the map that represents a particular distance on the earth's surface in words, e.g., 'one inch equals a mile.' The representative fraction (RF) expresses scale as a numerical ratio of map distance to earth distance, e.g., '1:63,360.' The RF has the advantage of being a unitless measure. Finally, a graphic scale bar uses a line of particular length drawn on the map and annotated to show how much earth distance it represents. A graphic scale bar has the advantage that it changes size appropriately when the map is enlarged or reduced. Alternatively, all three expressions of scale may refer to areal measurements rather than linear measurements, e.g., a 1-inch square may represent 1 square mile on the earth.

[edit] Inset

An inset map is a smaller map featured on the same page as the main map. Traditionally, inset maps are shown at a larger scale (smaller area) than the main map.[18] In this, they differ from locator maps, which show the primary map at a smaller scale (larger area) in the context of a region.[19] Inset maps are used by cartographers to highlight information that would be difficult to perceive at the scale of the main map. This highlighted information may include symbols or points of interest that add to the purpose of the map and address its audience. This techinque should be done for a higlighted area of significance, as the viewer will attach greater importance to the inset map. An effective inset map follows the same design principles as any map, even though it is featured in a smaller frame. The inset should be placed away from the visual center of the map but in a balanced location where the viewer will be able to clearly see it and recognize it is not an extension of the main map (this may be done with a border or text distinction).[20] A good inset should include use similar colors and text as the main map, and should include a legend and scale bar unless the cartographer makes these two clear in some other way.

[edit] Balance

Balance within cartography creates an overall stability. Applying correct balancing technique can greatly enhance the clarity of the map. An essential part of correctly balancing a map is knowing how different map features are weighted. A weight is applied based on how quickly an element draws the readers attention. Heavier elements tend be be dark, brightly colored, and larger. Lighter map features are generally dull colors, small, and lighter.

When balance is poor, map readers might be distracted. When balance is achieved, map readers will focus on the content of the map. Visual balance results from two major factors: weight and direction.[19]

[edit] Negative Space

Negative space is the space around and between the subject of an image. Negative space may be most evident when the space around a subject, and not the subject itself, forms an interesting or artistically relevant shape. Negative space in maps is useful in drawing attention to places where you want your audience to look. Oceans and other large bodies of water are good examples of negative space because they can either draw attention away from the purpose of the map if done incorrectly or they can be represented without taking over the visual hierarchy.

Using negative space properly will greatly affect the balance and aesthetic value of an image. By working with negative space in the image instead of positive space, one may find that they are better able to accurately portray the subject or positive space in a visually pleasing and complete manner. One way to understand the negative space in an image is to represent the subject in white and the rest of the image with black. This allows you to creatively work with space in order to find the right balance between negative and positive space.

[edit] Naming conventions

Most maps use text to label places and for such things as a map title, legend and other information. Maps are often made in specific languages, though names of places often differ between languages. So a map made in English may use the name Germany for that country, while a German map would use Deutschland and a French map Allemagne. A word that describes a place, using a non-native terminology or language is referred to as an exonym.

In some cases the proper name is not clear. For example, the nation of Burma officially changed its name to Myanmar, but many nations do not recognize the ruling junta and continue to use Burma. Sometimes an official name change is resisted in other languages and the older name may remain in common use. Examples include the use of Saigon for Ho Chi Minh City, Bangkok for Krung Thep and Ivory Coast for Côte d'Ivoire.

Difficulties arise, when transliteration or transcription between writing systems is required. National names tend to have well established names in other languages and writing systems, such as Russia for Роѝѝи̝ѝ, but for many placenames a system of transliteration or transcription is required. In transliteration, the symbols of one language are represented by symbols in another. For example, the Cyrillic letter Р is traditionally written as R in the Latin alphabet. Systems exist for transliteration of Arabic, but the results may vary. For example, the Yemeni city of Mocha is written variously in English as Mocha, Al Mukha, al-Mukhĝ, Mocca and Moka. Transliteration systems are based on relating written symbols to one another, while transcription is the attempt to spell in one language the phonetic sounds of another. Chinese writing is transformed into the Latin alphabet through the Pinyin phonetic transcription systems. Other systems were used in the past, such as Wade-Giles, resulting in the city being spelled Beijing on newer English maps and Peking on older ones.

Further difficulties arise when countries, especially former colonies, do not have a strong national geographic naming standard. In such cases, cartographers may have to choose between various phonetic spellings of local names versus older imposed, sometimes resented, colonial names. Some countries have multiple official languages, resulting in multiple official placenames. For example, the capital of Belgium is both Brussels and Bruxelles. In Canada, English and French are official languages and places have names in both languages. British Columbia is also officially named la Colombie-Britannique. English maps rarely show the French names outside of Quebec, which itself is spelled Québec in French.[21]

The study of placenames is called toponymy, while that of the origin and historical usage of placenames as words is etymology.

[edit] Map symbology

The quality of a map’s design affects its reader’s ability to extract information and to learn from the map. Cartographic symbology has been developed in an effort to portray the world accurately and effectively convey information to the map reader. A legend explains the pictorial language of the map, known as its symbology. The title indicates the region the map portrays; the map image portrays the region and so on. Although every map element serves some purpose, convention only dictates inclusion of some elements, while others are considered optional. A menu of map elements includes the neatline (border), compass rose or north arrow, overview map, scale bar, projection and information about the map sources, accuracy and publication.

When examining a landscape, scale can be intuited from trees, houses and cars. Not so with a map. Even such a simple thing as a north arrow is crucial. It may seem obvious that the top of a map should point north, but this might not be the case.

Color, likewise, is equally important. How the cartographer displays the data in different hues can greatly affect the understanding or feel of the map. Different intensities of hue portray different objectives the cartographer is attempting to get across to the audience. Additionally, there are certain accepted color associations for representing certain features on a map. For example, blue is traditionally used for bodies of water, green for natural areas, black to denote political boundaries. Not following these conventions when designing a map would lead to a confusing product.[22]

Similarly, the principle of visual hierarchy must be considered when choosing colors for a map. Bright, bold colors will draw the eye first and must be reserved for map elements of paramount importance. Lighter shades should be used for information that is important to place on the map, but that play a supporting role to the features at the top of the visual hierarchy. For example, a map showing the library branches of a city may have the actual branch locations symbolized as bright red dots, while the city divisions they serve would be shown as areas of pale pastel colors.

Today, personal computers can display up to 16 million distinct colors at a time, even though the human eye can distinguish only a minimum number of these (Jeer, 1997). This fact allows for a multitude of color options for even for the most demanding maps. Moreover, computers can easily hatch patterns in colors to give even more options. This is very beneficial, when symbolizing data in categories such as quintile and equal interval classifications.

Quantitative symbols give a visual measure of the relative size/importance/number that a symbol represents and to symbolize this data on a map, there are two major classes of symbols used for portraying quantitative properties. Proportional symbols change their visual weight according to a quantitative property. These are appropriate for extensive statistics. Choropleth maps portray data collection areas, such as counties or census tracts, with color. Using color this way, the darkness and intensity (or value) of the color is evaluated by the eye as a measure of intensity or concentration (Harvard Graduate School of Design, 2005).

[edit] Map generalization

A good map has to provide a compromise between portraying the items of interest (or themes) in the right place for the map scale used, against the need to annotate that item with text or a symbol, which takes up space on the map medium and very likely will cause some other item of interest to be displaced. The cartographer is thus constantly making judgements about what to include, what to leave out and what to show in a slightly incorrect place - because of the demands of the annotation. This issue assumes more importance as the scale of the map gets smaller (i.e the map shows a larger area), because relatively, the annotation on the map takes up more space on the ground. A good example from the late 1980s was the Ordnance Survey's first digital maps, where the absolute positions of major roads shown at scales of 1:1250 and 1:2500 were sometimes a scale distance of hundreds of metres away from ground truth, when shown on digital maps at scales of 1:250000 and 1:625000, because of the overriding need to annotate the features.

[edit] Aesthetics

Aesthetics deals with beauty or artistic appeal [1]. In cartography, the aesthetic aspects of a work influence the overall quality of that work. It is important for cartographic works to have aesthetic features because the aesthetic quality of a work has a significant impact on the overall quality and user friendliness of that work. [2]. When choosing between two similar maps, one usually chooses the map that has more aesthetic appeal. As cartographer Felix Ortag said, “A beautiful map is not necessarily a good map, but a good map should be beautiful.” [3]

Aesthetics in cartography can take one of two forms:

1. Responses to the map itself as an aesthetic object. This can be accomplished through details the cartographer chooses to put emphasis on, the color or combination of colors included in the map, or artistic form the map takes.

2. The subject of the map symbolized. An example of this would be the cartographer creating an expression of terrain which forms an imagined visual experience.

With these two forms in mind, a cartographer must always be aware of the audience the map is to be created for. Just as important as the audience is the theme of the map. Cartographers make aesthetic judgments when designing maps to ensure that the content forms a clear expression of the theme(s). [4]


[edit] See also

Atlas portal
Main article: Outline of cartography

[edit] References

  1. ↑ Kunzig, Robert; A Tale of Two Archeologists. Discover Magazine, May 1999.
  2. ↑ Meece, Stephanie; A bird’s eye view - of a leopard’s spots. The Çatalhöyük ‘map’ and the development of cartographic representation in prehistory. Anatolian Studies, 56:1-16, 2006.
  3. ↑ 2006. The Nippur Expedition. Oriental Institute, University of Chicago. Accessed 3 October, 2011.
  4. ↑ History of Cartography. Absolute Astronomy Web site. Accessed 3 October 2011
  5. ↑ J. L. Berggren, Alexander Jones; Ptolemy's Geography By Ptolemy, Princeton University Press, 2001 ISBN 0691092591
  6. ↑ Miyajima, Kazuhiko (1997). Projection Methods in Chinese, Korean and Japanese Star Maps from "Highlights of Astronomy" vol. 11B p. 714. Ed. J. Andersen. Norwell: Kluwer Academic Publishers.
  7. ↑ Needham, Joseph (1971). Part 3: Civil Engineering and Nautics. Science and Civilization in China. 4. Cambridge University Press. 569. ISBN 9780521070607. 
  8. ↑ 8.0 8.1 8.2 Sircar, D. C. C. (1990). Studies in the Geography of Ancient and Medieval India. Motilal Banarsidass Publishers. 327. ISBN 8120806905. 
  9. ↑ S. P. Scott (1904), History of the Moorish Empire, pp. 461-2.
  10. ↑ Globes and Terrain Models -- Geography and Maps: An Illustrated Guide, Library of Congress
  11. ↑ "Map Imitation" in Detecting the Truth: Fakes, Forgeries and Trickery, a virtual museum exhibition at Library and Archives Canada
  12. ↑ Devlin, Keith. The Millennium Problems. New York, New York: Basic Books, 2002. Pages 162-163.
  13. ↑ Robinson, A.H. (1953). Elements of Cartography. New York: John Wiley & Sons. ISBN. 
  14. ↑ Robinson, A.H. (1982). Early Thematic Mapping: In the History of Cartography.. Chicago: The University of Chicago Press.. ISBN. 
  15. ↑ MacEachren, A.M. (1995). How Maps Work. New York: The Guilford Press. ISBN. 
  16. ↑ Slocum, Terry; McMaster, Robert; Kessler, Fritz; Howard, Hugh. Thematic Cartography and Geovisualization (Third Edition). 2009 Pearson Education, Inc.
  17. ↑ 2010. Dykes, Jason; Wood, Jo; Slingsby, Aidan. Rethinking Map Legends with Visualization. giCentre - Department of Information Science, City University London. (PDF, 8.13 MB)
  18. ↑ (2006). Maps tutorial: The elements of a map, Maps and Cartography. Geospatial Resources and Map Collection, Ball State University Libraries. Retrieved 2 Oct 2011.
  19. ↑ 19.0 19.1 Besley, J. & Snider, K. (2010). Map design and layout, Rowan University. Retrieved 2 Oct 2011.
  20. ↑ Buckley, A. (2008). Cartographic design: Inset Maps, Esri Mapping Center. Retrieved 2 Oct 2011.
  21. ↑ This section based on: "Transliteration Systems". Illustrated Atlas of the World. Rand McNally. 1992. pp. A16-A17. ISBN 0-528-83492-4. 
  22. ↑ Pesses, M.; Color for cartography. Geography 222 lecture notes, Cartography for GIS, Antelope Valley College. Retrieved 3 October 2011.

[edit] Further reading

[edit] External links

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