Cartographer's Toolkit

At a conference for salmon scientists recently, I found a disconnect between those wanting to know more about GIS and those who wanted to teach about GIS. There was a lack of common vocabulary with which to describe the GIS procedures to the non-GIS professionals. GIS professionals cannot gain much traction with the non-initiated when we insist on using professional jargon with those who don’t have a clue what we are talking about.

For instance, there was need for explanation to point out that there is a difference between a GPS unit and the software that inputs data from a GPS unit (ArcPad, for example). Another phenomenon of note is a tendency to use the term Google Earth to mean aerial imagery as in, “Put the data on top of Google Earth.” This is a wide-spread colloquial usage that I’ve heard from many people.

On the subject of things that non-GIS people have trouble understanding, Twitter friend @tpstigers says, “Nobody ever understands projections, and I despair of working explanations.” For this particularly difficult concept I too flounder on a regular basis. The only time I feel I have truly successfully imparted the idea of projection to a non-GISer was the time when I sat with a scientist colleague in front of ArcGIS. With a map of the world on-screen I changed the projection on the fly several times. Seeing it change while I discussed the merits and drawbacks of various projections got the message across in a matter of several minutes.

Another Twitter friend, @ebwolf, states that “I always take a deep breath and seriously consider my audience before I say ‘large scale’ or ‘small scale’.” Considering I’ve had trouble with these terms even with other GISers I’d go a step further and advise to never use these terms if you can help it, at all. @geografa explains scale this way, “Large scale, large details. Small scale, small details.” @ebwolf chimes back in with reference to a Goodchild paper explaining that scale is a legacy concept anyway, so don’t use it. Personally, I prefer to use the simple (yet slightly dumber sounding) terms zoom in and zoom out as in, “Do you want that map to be zoomed in quite a bit or zoomed out?”

At the end of all this discussion @spara pitched in, “Now how to explain reference fraction in a meaningful way.” I don’t think I’m going to go there. If you have any grand ideas please let us know.