Module 10: Dot Mapping

The objective of this week's lab was to explore the concept of dot mapping in which each dot represents a certain amount of some phenomenon. The resulting map shows the 2010 population in South Florida. To create this map, I used ArcGIS Pro and data provided by UWF. I joined an Excel table of 2010 US census population data to a feature class of the South Florida counties and applied Dot Density Symbology. In order to exclude surface water areas from the dot density map, I applied a masking effect using a surface water feature class. To more accurately display the dot density in the areas outside the surface water, I clipped the county population with an urban land feature class. I included and labeled 4 major cities to provide geographic reference to the map. In addition, I uniquely symbolized the surface water by type. I then adjusted the dot size and dot value to find suitable values where the densest areas are just beginning to coalesce. In order to create the visual legend, I created mock data in a new map by creating a new feature class with 3 squares on a grid scaled to the dot map layout scale. I then added a field to the attribute table and used low, medium, and high values corresponding to the population data in Excel. I then applied the same population dot symbology to the new feature class. I used the snipping tool to create .png images of the squares, added them to the layout as pictures, and scaled them appropriately to the map. I drew rectangles around the images, grouped them, and added labels. 

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