The Role of Color Theory in Spatial Analysis

Spatial Analysis and Color Theory

Anytime I am consulting with a GIS client in regards to map design and layout, I almost always refer them directly to Colorbrewer.  I was fortunate to have a colleague recommend this website to me a couple years back and have referenced it several times when designing my own maps.

Cynthia Brewer, a Professor of Geography at Penn State, has dedicated her academic research to how color theory applies to Spatial Analysis.  Not only is Cynthia Brewer responsible for Colorbrewer, she has also authored a couple helpful books on map design; Designing Better Maps: A Guide for GIS Users and Designed Maps: A Sourcebook for GIS Users, both of which are available at Amazon.

There’s no denying Cynthia Brewer’s impact on Color Theory within Spatial Analysis

For the 2000 Census, Cynthia Brewer contributed a substantial amount of research to assist the US Census Bureau to redesign some of their thematic maps.  This lead to the development of a thematic color scheme that ranges from purple to orange, which has aided to increase the readability for those that are colorblind.

It is important for data visualization to be quick and concise.  The more difficult it is to distinguish between colors on a map, the more difficult it is for readers to interpret the purpose of said map.  Though purple and orange are not fit for every thematic map, it is important to select thematic map color schemes with your data and audience in mind.  It can become confusing to the reader if your map’s color scheme takes too long to make sense of.

The great thing about Colorbrewer is that it provides three different types of color schemes to choose from.  Sequential, Diverging and Qualitative color schemes can be selected – each of which provides several different color combinations that are easy to distinguish between.

The Colorbrewer website allows you to quickly choose between different thematic schemes and dynamically loads a sample map to illustrate how the selected color scheme would appear through an RGB digital monitor display.

Another great feature that Colorbrewer offers is color codes for three different color systems.   If you’re designing maps to be viewed digitally on an electronic device, Colorbrewer gives codes in RGB values.  If you’re designing a map to be printed out, then you can select the CMYK color system so as to optimize the way your thematic map appears on paper.  Finally, Colorbrewer gives the option to use HEX codes, which comes in handy if you planned on publishing a thematic map to the web.

There is no denying that Colorbrewer is a great tool when designing a thematic map.  Where Colorbrewer falls short is when it comes to applying styles to point and line objects.  Though the website can show sample roads and point symbols, it is obvious that the website is designed to work best with region or polygon based thematic shades.

Though it would be nice if Colorbrewer was optimized so as to prescribe display properties for roads and points, it isn’t necessarily a deal breaker.  The website does allow users to change the color used to display for roads, which is nice because it allows you to experiment with different design and layout styles that could compliment a potential thematic color scheme.

If you haven’t already, then I highly recommend visiting the Colorbrewer website.  It’s a great tool that has immense value when creating a thematic map for data visualization and spatial analysis.

Thanks a ton,
@ROB_MOR

Simon Garfield plugs his new book “On the Map” with Steve Inskeep on Morning Edition

On my way into the office this morning, I caught a Morning Edition segment on my local NPR affiliate about Simon Garfield’s new book entitled “On the Map.”  Garfield spoke with Steve Inskeep about everything from Ptolemy’s affect on Columbus’ voyage, to the Mercator Projection making Greenland appear larger than Africa, despite being a fraction of the size.

Reactions to Simon Garfield discussing “On The Map” with Steve Inskeep on NPR’s Morning Edition

One thing that I thought was particularly interesting was how the conversation between Garfield and Inskeep went to what the orientation, or the focal point, of a map connoted.  They discussed how old maps of Greece focused on the Island of Rhodes due to it being a popular vacation destination for Greeks.  They also discussed how maps on Smart Phones and GPS devices largely focus on the user and as such digital maps have become more egocentric in focus.

Ultimately, it was an interesting conversation and I highly recommend tuning in.  I believe this conversation is important in understanding the contemporary role that maps have on our digital lives.

Thanks a ton,
@ROB_MOR