Smith College Spatial Analysis Lab

September 2017 Mystery Map Solution

We concluded the first Mystery Map over the weekend with six entries! Despite the robust difficulty testing (an impressive sample size of two), all the contestants proved to be seasoned map puzzle solvers. The victory belongs to Susannah Howard, who identified all the parameters correctly and promptly (submitted the same day it was released, and from abroad no less!)

The map depicts the national monuments under review by the Department of Interior. The categories represent:

  • Red – subject to change
  • Green – set to remain the same
  • Beige – status unknown

The list of national monuments were provided in the Department of Interior EO 13792. The spatial data was gathered from USGS’s Protected Area of the U.S. database, NOAA, Bureau of Land Management, and National Park Service. The basemap consisted of TIGER boundary of U.S. states and world boundaries from Natural Earth. The cartographic logistics involved (for the GIS nerds inside all of us):

  • Simplify Polygon – Since the map encompasses the continental U.S., a detailed boundary of each state will appear unwieldy at this scale. By using this cartography tool, we get a visually comfortable depiction of the entire U.S.
  • Projection – This composite map uses two different projections. The U.S. national map uses US National Atlas Equal Area projection. The world map uses World Mollweide which is suitable for global data. By modifying the coordinate system, the center is placed on the Pacific Ocean.
  • Convert labels to annotation / convert to graphics – Converts map elements to graphics that can be tinkered without exporting to an external graphic software.