There are three broad categories of maps. The first, reference maps, generally show several types of spatial data without specific emphasis on one type over another. Reference maps can vary in their complexity and size, but generally include just the various geographic features that give a picture of the area being mapped, e.g. political boundaries, cities, topographic features and/or transportation routes. For instance, in the reference map of Thailand below, major cities, roads, railways, rivers and country borders are shown and differentiated by symbol and label, but the map is not made explicitly for navigation or exploration of those features.
Figure 1.1.1 Reference map of Thailand.
Credit: Courtesy of CIA
A second type of map is the thematic map, which as its name suggests, means the map has a specific theme or focus. This group of maps is extremely diverse. Thematic maps can vary in topic, complexity, purpose and kind of representation. They generally show characteristics, or attributes, of features that vary spatially. The attribute can vary in a qualitative or nominal way, e.g. categories of land cover; or the attribute can vary in a quantitative way, e.g. amount of precipitation. Thematic maps can represent data with points, lines, areas or volumes. Using visual variables (e.g. hue, lightness, pattern, shape) that fit logically with both the kind of feature being used for the symbols (e.g. point, line, area) and the way the attribute varies (qualitatively or quantitatively) is key to representing data in thematic maps. We will discuss symbolization in more depth in Lesson Two.
Figures 1.1.2 and 1.1.3 Thematic maps of Thailand. On the left is a categorical thematic map showing nominal classes of vegetation in 1974, and on the right is a quantitative thematic map showing ordinal classes of population density in 1974.
Credit: Courtesy of University of Texas
Special-purpose maps are a third category of maps. They lie somewhat between reference maps and thematic maps as they are often reference-like in their use but are made for specific types of users or pertain to a specific type of data. Navigational maps, like those in road atlases or nautical/aeronautic charts, are considered special-purpose maps, as are maps for certain industries or occupations, like Sanborn maps, soil maps, and municipal utility maps.
Figures 1.1.4 and 1.1.5 Navigational special-purpose maps. On the left is a portion of an Appalachian Trail map. The full PDF version of the map is available here:http://www.nps.gov/appa/planyourvisit/upload/APPA%20Map.pdf. On the right is a detail portion of NOAA Chart # 14909 showing ''Porte des Morts Passage'' and Washington Island, Wisconsin.
Credit: Appalachian Trail map courtesy of the National Park Service. Nautical chart courtesy of NOAA
Figures 1.1.6 and 1.1.7 Special-purpose maps. On the left is a Sanborn map from 1916 of the area around Indiana's state capitol building. Historically Sanborn maps were created to assess fire insurance liabilities; today they are often used in historical urban research. Full resolution image available here: Indianapolis Baist Atlas Plan # 2, 1916. On the right is a map of the sewer system of the City of El Cajon, CA. Full resolution image available here on page 112: http://media.esri.com/mapbook/volume26/index.html
Credit: Sanborn map courtesy of IUPUI University Library. Sewer system map courtesy of Esri and Tim Williams, Kimberly D. Dodson, and Desiree Taylor.
If you are interested in investigating this subject further, I recommend the following:
- Brewer, C. A. (2008). Designed Maps: A Sourcebook for GIS Users. Redlands, CA: Esri Press
Registered students in GEOG 486 will submit the majority of their projects for the class via the "Create Submission" link under the "Assignments" heading on the right-side menu. Most lessons will have more detailed information about what to upload on the "Lesson Project Tasks" page for each lesson. Below is generic information on how to submit an assignment, and how the Map Gallery works.
Use the link to upload assignments. The page should look similar to the image below.
On the "Create Assignment" page:
- Select the lesson number and assignment you are submitting from the required "Assignment Type" dropdown, e.g. "Lesson 1 map"
- Type your name in the required "Author" field
- Type the title of your map or assignment in the required "Title" field.
- If you are submitting an image file, browse to the image using the "Browse" button located under the "Map Image File" section. Click the "Upload" button upon selection of the image. Image files must be either a png, gif, or jpeg.
- If you are submitting a document that is not an image, browse to the file using the "Browse" button located under "Assignment File" section. Click the "Upload" button upon seleciton of the file. Document files must be either a txt, zip, pdf, doc, and docx.
- Click "Save" at the bottom of the page when you are ready to submit your assignment.
After you save the submission, you will see your uploaded image and/or document surrounded by a pink box. This means that the page is not public, and the only people that can see it include the person submitting it, the instructor, and site administrators.
If map assignments are made public (by the instructor), they become visible publically in the Map Gallery. The Map Gallery functions in two ways, 1) like an album of images that can be paged through, and 2) like a discussion forum for each image.
Below is an image showing an example initial view of the Map Gallery (but images may differ).
What to be aware of in the Map Gallery
- Changing the Assignment Type, via the drop-down menu, will change the set of maps/images shown, based on the assignment designated by you, and peers, upon upload.
- The titles along the top of the images are links that lead to the comment page for each image.
- Clicking on the images themselves will zoom into the maps. There you can page through all the maps in the gallery with the navigation buttons or keyboard arrows. But to get to the comments you have to go back to the main Map Gallery page and click on the title(s).
How we will use the Map Gallery
We will use the Map Gallery throughout GEOG 486, but in different ways in different lessons.
- In Lesson 1, we use the Map Gallery to see and discuss the maps we chose to review for the visual communication portion of the lesson assignment.
- In Lessons 3, 4, 5, 6, and 8, we use the Map Gallery to view each other's work after all work (for each lesson) has been submitted. The goal is to get ideas from each other and to open up discussion on map design.
- For the Capstone Project we use the Map Gallery to do our Peer Reviews and see each other's work.
Posting Comments to the Map Gallery
To post a comment on a map:
- Click on the Title link that is above the map image when viewing the main Map Gallery page.
- Click the "add new comment" button under the image to add a comment unrelated to another comment.
- If replying to a previous comment, click the "reply" button under the comment you are replying to.
- Make sure to click "Save" at the bottom of any page to submit the comment.
- You will be able to edit your own comments, but not others'.
NOTE: Earlier comments appear before later ones, comments are only visible to people logged-in to GEOG 486, and comments will be cleared at the end of each term.
If you have any questions, or any of the information on this page is unclear, post in the "General Questions and Discussion" forum in Canvas, or email me.