Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN>Revised 2007 LULC based on re-interpretation by AIS using the 2007 Aerial Imagery. This revision was part of the contract to update the 2012 LULC for the State of Delaware. Many errors were detected in the 2007 LULC interpretation and AIS provided correction for those errors.</SPAN></P></DIV></DIV></DIV>
Service Item Id: 7e16121c034a4eccbcba07c69351a0ce
Copyright Text: Aerial Information Systems, Inc. (AIS)
Description: The 2012 Land Use Land Cover (LULC) update was performed using computer interactive heads-up digitizing techniques and ArcGIS software. The baseline datasets were year 2012 digital CIR orthophotos and the State’s existing 2007 LULC data. The data was digitally subdivided into working production modules based on the 1:24,000 scale USGS topographic quadrangle system. The LULC update was performed per the modified Anderson, et al., LULC classification and 2 acre minimum mapping unit (140’ width) established for the State’s previous LULC Update projects. The work was performed by Aerial Information Systems, Inc. (AIS) of Redlands, California.AIS staff analysts compared the State’s existing 2007 LULC data to the 2012 project imagery. 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.
Service Item Id: 7e16121c034a4eccbcba07c69351a0ce
Copyright Text: Mapped by Aerial Information Systems, Inc., for the Delaware Office of State Planning Coordination
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN>Land Use dataset for New Castle, Kent, and Sussex Counties in the State of Delaware. This Land Use dataset represents land use classification for the State of Delaware for two time periods: 2017 and 2022. This dataset originates from Aerial Information Systems, Inc who were tasked with updating the state of Delaware's existing 2012 GIS Land Use/Land Cover (LULC) and Impervious Surface datasets to 2017 conditions. The UVM Spatial Analysis Lab received the updated 2017 layer, and using a detailed manual review system, corrected and edited this dataset to 2017 orthorectified imagery of the State of Delaware as necessary. Additionally, the dataset was edited to accommodate an update that includes 2022 land use classification, using a detailed manual review system and 2022 orthorectified imagery of the State of Delaware. The manual review was carried out at a scale of 1:5000, and all observable errors were corrected. The land use codes used for this dataset are derived from the metadata of Delaware's existing 2012 GIS Land Use/Land Cover (LULC) and Impervious Surface datasets</SPAN></P></DIV></DIV></DIV>
Service Item Id: 7e16121c034a4eccbcba07c69351a0ce
Copyright Text: University of Vermont Spatial Analysis Laboratory in collaboration with State of Delaware.