Embedded Files
Learning objectives of Module 2
GIS is a way of working with maps in a digital medium rather than in hard copy. This allows several advantages, such as essentially becoming virtual reality where interactions are more immediate. Digital implies a technological component that allows for keeping up with new and different approaches to mapping, involving different disciplines into the process, and incorporating social media. There are several primary advantages of GIS versus paper, such as variable scale, variable extent, animation, 3-D, supplementation, and customization. In this exercise, we learned how to generate good maps in the digital medium. Visualization assists map users to interpret what the map is attempting to show, to validate the data, and to explore the data in different ways.
Problem:
Symbology can be a powerful means of expressing the concepts we want the map to express. In this exercise, we experimented with the shapes, sizes, textures, colors, etc. of the symbols we placed on the map.
Analysis Procedure:
After opening the map document, it was important to explore the data to understand the extent of the information it intended to convey. Following this, the data was categorized, and symbols and labels were optimized for the features, including line and point features, they were representing. Value ranges were defined and symbol sizes adjusted to represent these ranges. To improve the viewing quality, texture was added to the map document, including hillshade.
Results:
A map was generated that showed the number of employees in the area around San Diego, CA (Figure 1). The larger the colored circle, the more employees were represented in that particular area.
Figure 1. Map showing colored symbols for employee number, road features, and districts around San Diego, CA.
Application and Reflection:
Visualization assists map users to interpret what the map is attempting to show. With the map generated for mushroom sightings along the trails of the Eno River State Park (see Our Mushroom Hunting), it was important to distinguish between main trail segments (maintained by Eno River State Park) and others. Additionally, there are a number of access points to the area, that may or may not be well defined. In order to recognize where those are on the map document, symbols are available that can show this information. Eno River State Park is a reasonably large area with several distinct access points as well as terrain types. Distinguishing these areas from one another may assist in cateloging which mushroom varieties can be found where and showing this information in a clear manner to those who may be interested in knowing.
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