This week, I was introduced to two new concepts - Field GIS Mapping and Projections. I enjoyed the Field GIS Mapping project and had little issues working with Field Maps or ArcGIS online. I spent the majority of my time this week working with the Map Projection Comparisons portion of the project.The Map Projection comparisons portion of the project compared the Albers Conical Equal Area map with two others, State Plane N and UTM 16 N. The Albers Conical Equal Area, which is maintained within the Florida Geographic Data Library, is the standard projection used for the State of Florida. I observed that both Miami-Dade and Polk Counties, which are larger counties in area and population, both had discrepancies in calculated area (in square miles) compared to Escambia and Alachua Counties. It is possible that the calculated area was different in the larger counties due to map projection distortion. UTM16N and State Plane N are based on conformal projections, while Albers is an equal area projection. Equal area projections typically display true proportion, but will distort the shape. Conformal projections retain the correct shape of small areas, but the size itself may be distorted.
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