Base maps can be created for a multitude of purposes- orientation, hiking, field studies (see images), and they don’t need to be high tech. They should, however, contain some or all of the five elements of a good map: scale, direction, key (if using symbols), title, and border.
Neighborhood Sketch Map:
When I taught high school geography, one of the first class exercises assigned was to sketch a map of Canada using no other source than memory. It was interesting, to say the least. Try it.
Geographers use the tools of geography to study the environment around them. In doing so, they basically attempt to answer four questions: what, where, why, and what are the effects? Where possible, they go beyond books and memory and visit a site. By walking around a neighborhood, for instance, information can be gathered just by looking. To communicate this information to others in an informal way, geographers can start with a sketch map.
A simple exercise for anyone is to create a map of their neighborhood: the adjacent areas near to or in the vicinity of where they live. The first step is to draft a rectangle on a piece of paper. Then draw a map within the rectangle- strictly from memory- to include what you consider to be your neighborhood. You might include the following:
- roads
- your house, other houses, stores
- paths
- short cuts, detours
- familiar smells
- landmarks: trees, objects
- streams
- vacant lots
- north direction
- unique features e.g. broken fence
Using the features recorded from memory on your neighborhood sketch map, you might set up a chart and complete the following questions:
- Summarize the physical and human features mapped by listing them under a ‘what’ column
- Complete by answering the where, why, and effects columns for each ‘what’.
- Underline or asterisk any effects that you personally consider a problem.
- Suggest solutions to the problems identified.
Mapping to Scale:
Map scales are essentially ratios (e.g. 1: 10 000) and represent features on the ground. But those features (e.g. school building, field house, camp site, or tree) require appropriate map scales in order to be represented accurately. Therefore, we classify map scales, based on the size of the features they are showing: a smaller or larger scale. It can be confusing, however, because it is opposite to what you might think. For instance, 1: 5 000 is a larger scale (but smaller number) than 1:15 000 which is considered a smaller scale (but larger number). The following exercise suggests you create a neighborhood map drawn to a very large scale of 1: 2 000.
The objective is to produce a map to scale that shows the following features within 200 meters left and right of your house (Scale- l cm to 20m, and only one side of the street):
- property sizes
- dwellings, businesses, factories
- parks, woodlots
- sidewalks, boulevards, driveways, roads, significant trees
- one unique feature that makes the area interesting to you
The steps are as follows:
- Determine your pace: walk ten normal steps from a beginning point, measure the distance, and then divide by 10 to obtain your average pace. (repeat several times for accuracy)
- Draw a draft sketch of everything that you will eventually measure and draw to scale.
- Take measurements (pacing), and record them on the sketch
- Draw the features to scale (divide all measurements by 20 to convert to centimeters)
Remember to include the five basic elements of map making, namely:
- scale- use any or all forms and place it in the legend
- legend- use appropriate symbols and place the legend in a location on the map that has enough space
- north arrow- keep it simple
- border
- Appropriate title (block letters) centered in its own space
Using a GPS Unit:
Good map makers can create without the use of high tech gadgets. However, GPS units are useful for pinpointing coordinates (location). Plus, you can download an appropriate topographic map to the unit.
The key to good mapping is to not map everything. Only map what is useful to the user. If you want everything, take a picture. A map is a model of reality. Furthermore, cluttered maps are difficult to read. Stephen MacDonald, writing in The Monograph, suggested an exercise for mapping the types (regular, recycling, organic) and locations of trash bins on a school property. His exercise included the following steps:
- establishing the coordinates (Waypoints) of the corners of the school grounds
- using a GPS unit to determine the (Waypoint) coordinates of existing types of trash bins which will be later drawn using symbols created for the purpose
The steps for drawing a finished map of trash-bin locations using a grid are as follows:
- Label the vertical and horizontal grid lines based on the GPS-established coordinates of the corners of the school grounds.
- Plot the coordinates of the bins on the labeled grid.
- Complete with map elements: symbols and a key, a title, direction arrow, approximate scale (compare a real distance e.g. side of the school with the map distance, and then create a ratio) and a border.
The Georgia Orienteering Club points out that there are situations in which GPS data will not record data with adequate accuracy for map making. These include:
- When cloud cover is absorbing and reflecting satellite signals.
- Leaf cover is blocking the view of the satellites
- At any one time satellites are positioned poorly for optimum reception.
To judge the accuracy of your GPS, the GOC suggests following a line (e.g. a trail) up and back to your start. The two line plots should correspond to each other precisely. If successive recordings of a line do not match very closely, do not use the GPS data on your map. In many situations, traditional methods (compass bearings and pacing) may be more accurate than GPS data.
Advanced Computer Mapping:
For the most part, most of the world has already been mapped and photographed. With mapping software like OCAD you can scan in what already exists. The first step is to collect existing maps. Many local governments are now putting property boundaries and recent aerial photographs online.
Furthermore, as explained on the OCAD website, “if you have access to basic vector geodata, then you can import it and automatically assign symbols.” As Math Works explains, “vector geodata includes points, lines, and polygons that represent geographic objects. Vector geospatial data is used to represent point features, such as cities and landmarks; linear features, such as rivers and highways; and areal features, such as bodies of water and voting districts.”
But good mapping software is pricy: OCAD professional versions which allow the import of GPS data are approximately $1500 Canadian (roughly half price if used academically).
A Public Forum:
If you are truly interested in the art and science of cartography you might like to visit Carto Talk, a public forum for cartography and design. Or, perhaps you want to find employment in the field of cartography, GIS and design? There are even job postings on the site. No matter your pleasure, happy mapping.
Sources:
- Mapper's Guide: Preparing a Basemap. Georgia Orienteering Club.
- OCAD- Smart for Cartography. OCAD
- Stephen MacDonald. It's All About Trash. The Monograph. Vol. 61, Issue No Fall 2010.
- Understanding Vector Data. Math Works
James Gibson - James Gibson is a retired teacher and small business owner. He is a published writer and has a wide spectrum of interests.
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