Cartography

MAPMAKING IS ONE OF MY FAVORITE THINGS TO DO: partially because I know that good maps can tell a story in a compact form, but partially because it allows me to see hidden patterns and unexpected oddities. Mapmaking also allows me to express myself artistically.

Mapping software

I use a state-of-the-art Geographic Information System (GIS) from ESRI to create polished maps for use in planning sessions, in public presentations, on Internet sites, in large-format posters, on outdoor signs, and to accompany reports or books.

Although most of the time GIS software is the right mapmaking tool, occasionally an alternative is more desirable. Google’s KML language provides a simple structured way to annotate Google Earth and Google Maps with descriptions, place-markers, paths and polygons. I see promise in this newest addition to the mapping world: it combines a heavyweight dataset with a lightweight language, making it easy to deploy Internet-based spatial data.

My days of making maps using vellum and India ink with Lettraset dry transfers are long over—replaced by the superiority of computers—but GIS software isn’t the only way to make presentation-quality maps with computers: occasionally I make special maps using Adobe Illustrator, when the “art” of the cartography needs to be masterful.

Map products

Many types of maps can be created with today’s software, each type following a form that reflects their intended use.  I’ve drafted maps for reference, for working sessions, for planning purposes, for portraying complex data, and for telling stories. Here’s the nomenclature I use to classify the types of maps I’ve created:

Reference maps—with generous amounts of jurisdictional data, textual labels, symbology, and crosshair grids—are useful for locating the position of things in relation to one another. Reference maps are the most common type of map that people use on a daily basis.

Work maps—with plain backgrounds and simple symbology—are useful for teamwork planning sessions, where annotations can freely be added by team members.

Planning maps—where a matched set of maps are created, each with the same scale and extent, but with distinct map layers—are useful for understanding a region’s complexity and for making good placed-based decisions. Typical layers for planning maps include: geology, soil, topography, vegetation, cadastral data, jurisdictions, infrastructure, etc.

Thematic maps—where demographic and statistical data are charted spatially—are useful for presenting analytical results.  Thematic maps can express the hidden patterns behind complex data in ways that reveal new insights to the viewer.

Story maps—where the location of events, as they unfolded, are placed in relation to one another—are useful for telling a story as it traverses a landscape. The writings of field journals, exploratory campaigns, reconnaissance trips, and even natural disasters, can all be enhanced with story maps.

Time series maps—which chart the change in landscape features over time, through the use of a fixed frame of reference—are useful for projecting trends into the future.

Spatial analysis

Several powerful tools are available for use with GIS software that allow sophisticated analyses to be conducted on data sources.  These mathematical transformations enable two or more map layers to be manipulated through simple operations such as intersect and union, or through more advanced operations such as proximity and buffer.

By using spatial analysis, complex inferred data can be expressed from pre-existing datasets, providing answers to questions like: “How many residences are situated within 100 meters of a creek?,” or “Which hillsides have critical slopes and loose soils that might lead to landslides?” These types of analyses are not difficult to conduct, but the general public’s familiarity with this approach to the study of the Earth hasn’t yet reached the point where we are asking the right questions.

As a geographer, I often help clients to rethink their problems and to formulate more sophisticated questions.  When pursued with a spatial analysis approach, solutions to these problems can produce deeper results.

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The old cliché, "a picture is worth a thousand words," may be true, but I like to add "a map is worth a thousand pictures."