2012 Land Use Land Cover

Every polygon was reviewed for change, accuracy of polygon boundaries, and adherence to the 2012 LULC classification and mapping criteria. Polygon boundaries and codes were modified as necessary through the addition of new lines and codes or the modification of existing arcs. In addition, large obvious errors in the 2007 data were retroactively (‘retro”) corrected.

The “retro” mapping process helps to ensure a more accurate baseline dataset for change analysis studies. The 2012 LULC interpretations were incorporated directly into the baseline 2007 LULC coverage to create a final composite coverage containing LULC information for both eras. Each polygon in the composite coverage was assigned an item for 2012 and 2007.

Where no LULC change had occurred, the LULC class for both item years remained the same. Where a LULC change did occur, new boundaries were added to the data set as needed, subdividing the existing 2007 polygon, and the polygons were attributed for the appropriate 2012 LULC type. This method ensured that the different layers seamlessly co-registered to each other, creating a sliver free coverage for use in change analysis studies.