Cartographic symbology. By proj jasper

meaning of symbols, types of symbols, context of symbols in cartography, symbology in GIS, uses of map symbols, types of map symbols

1. CARTOGRAPHIC SYMBOLOGY GROUP 1

2. CARTOGRAPHY SYMBOLOGY Symbology, in the context of Cartographic design, is the use of graphical techniques to represent geographic information on a map . Map symbols for geographic features include Visual variables such as color, size, and shape . Generically, a symbol is an object, picture, written word, sound, or a particular mark that represents something else by association, resemblance, or convention. For example, Roman numerals are symbols for quantitative values and personal names are symbols representing individual people.

3. Semiotics Semiotics is the science and study of signs and symbols, including language and other systems of communication. It is a discipline that is very similar to philosophy of language, in that they both share a common focus on language. It is an important theoretical framework for Cartography, specifically the design of effective map symbology. The Science of semiotics was originally founded by Charles Sanders Peirce in the 1860s, its theories were first applied directly to cartography by Jacques Bertin in his 1960 book, “ The semiology of graphics ”.

4. Map Symbols Some example of map symbolization include: A title describe the theme or subject of a map Frame or grid line: a frame is use to enclose a map Compass or north arrow provides orientation A linear scale or bar scale shows relationship between distance on the map and distance on the Earth surface Map legend describes or explain the symbols used on a map.

5. Classification Of Map Symbols by Dimension Maps communicate their messages through symbols--drawn graphics that represent spatial phenomena such as objects, places, or attributes . At their most basic, map symbols can be categorized by Dimension: points , lines, and regions; each can be portrayed using symbology . These symbols are commonly used to describe different features mapped. For example, cities or airports are commonly represented as point symbols (depending on scale), roads or railroads are usually represented by line symbols and the cities, lakes, or forests are common examples of region symbols.

6. POINT SYMBOL A point symbol represents a geographic feature or event characterized by location and attributes. Its location can be represented by a single " x,y " coordinate pair, while attributes can be many. For example, a populated place or a mine site can be represented by a point symbol. Eg . settlement, trees, poles.

7. LINE SYMBOL A line symbol represents a geographic feature characterized by linear dimension, but not area. In digital technology, a line is a sequence or stream of point coordinates with a node at each end (vector data) that symbolizes a linear feature such as a road, river, or boundary. Example roads, rivers, contour lines, rail line etc.

8. AREA SYMBOL An area symbol represents a closed geographic surface feature, two-dimensional geometric region, or a polygon. A census division, a lake, or a province (any geographically defined surface) are examples of area features.

9. EXAMPLE OF POINT, LINE AND AREA SYMBOL

10. Classification of map symbols by shape Map symbols can also be categorized by shape: P ictorial/descriptive symbols G eometric/abstract symbols Letter or number symbols.

11. PICTORIAL/DESCRIPTIVE SYMBOLS Symbols that are pictorial look like the features that they represent. These symbols tend to reflect the shape and color of the feature. For example, the symbol for a picnic site may be a picnic table, or the symbol for a vegetated area may be a green polygon.

12. GEOMETRIC/ABSTRACT SYMBOLS Symbols described as abstract may be any geometric shape assigned to represent a feature. For example, a series of graduated dots and/or squares could represent populated places on a reference map. On the other hand, colored or patterned polygons could represent varying concentrations of people, on a population density map.

13. IMAGE EXPLAINING THE SHAPE OF SYMBOLS AS USED IN MAP

14. TYPES OF MAP SYMBOLS Image or iconic symbols : look like the real world features, for example a tree icon to represent a forest or green denoting vegetation . Functional symbols : directly represent the activity that takes places at the represented features. For example a picture of skier to represent a ski resort or a tent to represent a campground. Conceptual symbols : directly represent the concept related to the represented features. For example a dollar sign to represent an ATM, or star of David to represent a Jewish synagogue. Conventional symbol : Do not have any intuitive relationship but are so commonly used that map readers eventually learn to recognize them. For example, a red line to represent a highway or a cross to represent a hospital. Ad hoc symbol : do not have any intuitive relationship in fact, the symbols is often used only for a single map. For example a polygon in a chloropleth map filled with a particular shape of red that means high income these symbols require effective legends/labels to be correctly interpreted.

15. CONCLUSION Cartographers typically have a great degree of freedom to design and implement map symbology according to their personal tastes, creativity, and innovation. However, in some applications, the need for consistency and immediate usability has driven the development of standard sets of symbols. A good symbol is easily recognizable (i.e., connected to the geographic features and concepts it represents), is aesthetically pleasing, and works in harmony with other symbols (for example, as part of a clear visual hierarchy). A legend is needed to explain the meaning of the symbols that cannot safely be assumed to be intuitive . The choice of symbology is a crucial part of cartographic design; the goal is for the map reader to spend less time figuring out what the symbols mean, and thus more time using the symbols to understand the World.