Wednesday, October 19, 2016
Creating non-spatial and "not quite true" spatial figures in GIS
The solution? What I call a "not quite true" spatial map. In the figure below we see that each bold box shows a trapping grid and each smaller box is a trapping station. The colors represent the intensity of some value. It may be the number of animals caught in the traps at the locations or some habitat variable having to do with plant cover or soil type. The reason why it is "not quite true" spatial is that distances among trapping grids is much larger than they are in real life and distances between individual traps isn't always exactly even. Nonetheless it shows spatial patterns in a succinct and compact form.
This is a nice reminder of how GIS can be a powerful tool for all sorts of visualizations, not just for maps. Using GIS we can very easily change color schemes using different kinds of classification s (i.e. natural breaks, quantiles, equal intervals, etc.), edit individual lines and polygons, convert from raster to vector formats. Some of this stuff is tedious to do in other types of software.
We're probably all familiar with some examples of "not quite true" spatial maps. Subway maps are a prime example. They are designed to show relative space, but distance isn't always accurate in the true geographic sense. However, we can also take raster GIS outside of the realm of normal geographic space and actually use GIS for displaying things like time series or even data space. More on that later.