Positive openness rasters for the Greater Raleigh Area, North Carolina

Rasters of positive openness and positive openness difference in the Greater Raleigh, NC Area based on 1-meter high-resolution lidar-derived digital elevation models (DEMs). This dataset contains positive openness rasters for 2013, 2015, and 2022 and one positive openness difference raster. The positive openness difference raster represents the difference in positive openness values between the years 2015 and 2022. The 2015 and 2022 positive openness rasters were selected for differencing because of the superior quality level (QL2) of base lidar data used to develop the positive openness rasters compared with the poorer quality level (QL3) of base lidar data used to develop the 2013 positive openness raster. Positive openness uses a line-of-sight approach to measure the surrounding sixteen zenith angles viewed above the landscape surface out to a specified distance. The raster cell value represents the average of all sixteen angles. A positive openness value of 90 degrees indicates a flat surface. Positive openness values less than 90 degrees indicate varying degrees of concavity; positive openness values greater than 90 degrees indicate varying degrees of convexity. Positive openness was calculated with the Relief Visualization Toolbox v 2.2.1 (https://www.zrc-sazu.si/en/rvt) with the search radius set to 18 meters (approximately 60 feet). All files are available as Cloud Optimized GeoTIFF, meaning they are formatted to work on the cloud or can be directly downloaded.