In May 2013, the Grand Canyon Monitoring and Research Center (GCMRC) of the U.S. Geological Survey’s (USGS) Southwest Biological Science Center (SBSC) acquired airborne multispectral high resolution data for the Colorado River in Grand Canyon in Arizona, USA. The imagery data consist of four bands (blue, green, red and near infrared) with a ground resolution of 20 centimeters (cm). These data are available to the public as 16-bit geotiff files. They are projected in the State Plane (SP) map projection using the central Arizona zone (202) and the North American Datum of 1983 (NAD83). The assessed accuracy for these data is based on 91 Ground Control Points (GCPs), and is reported at 95% confidence as 0.64 meters (m) and a Root Mean Square Error (RMSE) of 0.36m. The airborne data acquisition was conducted under contract by Fugro Earthdata Inc. using two fixed wing aircraft from May 25th to 30th, 2013 at altitudes between 2440 meters to 3350 meters above mean sea level. The data delivered by Fugro Earthdata Inc. were checked for smear, shadow extent and water clarity as described for previous image acquisitions in Davis (2012). We then produced a corridor-wide mosaic using the best possible tiles with the least amount of smear, the smallest shadow extent, and clearest, most glint-free water possible. During the mosaic process adjacent tiles sometimes had to be spectrally adjusted to account for differences in date, time, sun angle, weather, and environment. We used the same method as described in Davis (2012) for the spectral adjustment. A horizontal accuracy assessment was completed by Fugro Earthdata Inc. using 188 GCPs provided by GCMRC. The GCPs were marked during the image acquisition with 1m2 diagonally alternated black and white plastic panels centered on control points throughout the river corridor in the GCMRC survey control network (Hazel and others, 2008). The Root Mean Square Error (RMSE) accuracy reported by Fugro Earthdata Inc. is 0.17m Easting and 0.15m Northing, or better, depending on the acquisition zone. The 16-bit image data are stored as four band images in embedded geotiff format, which can be read and used by most geographic information system (GIS) and image-processing software. The TIFF world files (tfw) are provided, however they are not needed for many software to read an embedded geotiff image. The image files are projected in the State Plane (SP) 2011, map projection using the central Arizona zone (202) and the North American Datum of 1983 (NAD83). A complete detailed description of the methods can be found in the associated USGS Data Series 1027 for these data, https://pubs.er.usgs.gov/publication/ds1027.

Lake Mead is a large interstate reservoir located in the Mojave Desert of southeastern Nevada and northwestern Arizona. It was impounded in 1935 by the construction of Hoover Dam and is one of a series of multi-purpose reservoirs on the Colorado River. The lake extends 183 km from the mouth of the Grand Canyon to Black Canyon, the site of Hoover Dam, and provides water for residential, commercial, industrial, recreational, and other non-agricultural users in communities across the southwestern United States. Extensive research has been conducted on Lake Mead, but a majority of the studies have involved determining levels of anthropogenic contaminants such as synthetic organic compounds, heavy metals and dissolved ions, furans/dioxins, and nutrient loading in lake water, sediment, and biota (Preissler, et al., 1998; Bevans et al, 1996; Bevans et al., 1998; Covay and Leiker, 1998; LaBounty and Horn, 1997; Paulson, 1981). By contrast, little work has focused on the sediments in the lake and the processes of deposition (Gould, 1951). To address these questions, sidescan-sonar imagery and high-resolution seismic-reflection profiles were collected throughout Lake Mead by the USGS in cooperation with researchers from University of Nevada Las Vegas (UNLV). These data allow a detailed mapping of the surficial geology and the distribution and thickness of sediment that has accumulated in the lake since the completion of Hoover Dam. Results indicate that the accumulation of post-impoundment sediment is primarily restricted to former river and stream beds that are now submerged below the lake while the margins of the lake appear to be devoid of post-impoundment sediment. The sediment cover along the original Colorado River bed is continuous and is typically greater than 10 m thick through much of its length. Sediment thickness in some areas exceeds 35 m while the smaller tributary valleys typically are filled with less than 4 m of sediment. Away from the river beds that are now covered with post-impoundment sediment, pre-impoundment alluvial deposits and rock outcrops are still exposed on the lake floor.

Forest management traditionally has been based on expectation of a steady climate. In the face of a changing climate, management requires projections of changes in the distribution of the climatic niche of the major species and strategies for applying the projections. We prepared climatic habitat models incorporating heatload as a topographic predictor for the 14 upland tree species of southwestern Colorado, USA, an area that has already seen substantial climate impacts. Models were trained with over 800,000 points of known presence and absence. Using 11 climate scenarios for the decade around 2060, we classified and mapped change for each species. Projected impacts are extensive. Except for the low-elevation woodland species, persistent habitat is rare. Most habitat is lost or threatened and is poorly compensated by emergent habitat. Three species may be locally extirpated. Nevertheless, strategies are described that can use the projections to apply management where it is likely to be most effective, to facilitate or assist migration, to favor species likely to be suited in the future, and to identify potential climate refugia.

In May 2021, the Grand Canyon Monitoring and Research Center (GCMRC) of the U.S. Geological Survey’s (USGS), Southwest Biological Science Center (SBSC) acquired airborne multispectral high resolution data for the Colorado River in Grand Canyon in Arizona, USA. The imagery data consist of four bands (Band 1 – red, Band 2 – green, Band 3 – blue, and Band 4 – near infrared) with a ground resolution of 20 centimeters (cm). These image data are available to the public as 16-bit GeoTIFF files, which can be read and used by most geographic information system (GIS) and image-processing software. The spatial reference of the image data are in the State Plane (SP) map projection using the central Arizona zone (FIPS 0202) and the North American Datum of 1983 (NAD83) National Adjustment of 2011 (NA2011). The airborne data acquisition was conducted under contract by Fugro Earthdata Inc (Fugro) using two fixed wing aircraft from May 29th to June 4th, 2021 at flight altitudes from approximately 2,440 to 3,350 meters above mean sea level. Fugro produced a corridor-wide mosaic using the best possible flight line images with the least amount of smear, the smallest shadow extent, and clearest, most glint-free water possible. The mosaic delivered by Fugro was then further corrected by GCMRC for smear, shadow extent and water clarity as described in the process steps of this metadata and for previous image acquisitions in Durning et al. (2016) and Davis (2012). 47 ground controls points (GCPs) were used to conduct an independent spatial accuracy assessment by GCMRC. The accuracy calculated from the GCPs is reported at 95% confidence as 0.514 m and a Root Mean Square Error (RMSE) of 0.297 m.

Lake Mead is a large interstate reservoir located in the Mojave Desert of southeastern Nevada and northwestern Arizona. It was impounded in 1935 by the construction of Hoover Dam and is one of a series of multi-purpose reservoirs on the Colorado River. The lake extends 183 km from the mouth of the Grand Canyon to Black Canyon, the site of Hoover Dam, and provides water for residential, commercial, industrial, recreational, and other non-agricultural users in communities across the southwestern United States. Extensive research has been conducted on Lake Mead, but a majority of the studies have involved determining levels of anthropogenic contaminants such as synthetic organic compounds, heavy metals and dissolved ions, furans/dioxins, and nutrient loading in lake water, sediment, and biota (Preissler, et al., 1998; Bevans et al, 1996; Bevans et al., 1998; Covay and Leiker, 1998; LaBounty and Horn, 1997; Paulson, 1981). By contrast, little work has focused on the sediments in the lake and the processes of deposition (Gould, 1951). To address these questions, sidescan-sonar imagery and high-resolution seismic-reflection profiles were collected throughout Lake Mead by the USGS in cooperation with researchers from University of Nevada Las Vegas (UNLV). These data allow a detailed mapping of the surficial geology and the distribution and thickness of sediment that has accumulated in the lake since the completion of Hoover Dam. Results indicate that the accumulation of post-impoundment sediment is primarily restricted to former river and stream beds that are now submerged below the lake while the margins of the lake appear to be devoid of post-impoundment sediment. The sediment cover along the original Colorado River bed is continuous and is typically greater than 10 m thick through much of its length. Sediment thickness in some areas exceeds 35 m while the smaller tributary valleys typically are filled with less than 4 m of sediment. Away from the river beds that are now covered with post-impoundment sediment, pre-impoundment alluvial deposits and rock outcrops are still exposed on the lake floor.

Loudoun County annually obtains leaf-off, aerial imagery in the spring. Since 2004, the County has utilized this imagery to support the development of an annual digital orthophoto base. In 2021, the imagery was captured with a Vexcel Ultracam Eagle digital camera, in 4-band (R,G,B, and NIR) format. These files contain 1-foot ground-resolution, 8-bit, 4-band orthorectified aerial image map products in GeoTIFF version 6.0 file format. GeoTIFF files are uncompressed raster images complete with TFW coordinate information. The aerial imagery project encompasses the entire land area of the County of Loudoun, VA. Images were flown during leaf-off conditions and cover 5000' by 5000' and are tiled according to the VBMP 200-scale gridding schema (Virginia Geographic Information Network)."March 2021 Photography flown by the Sanborn Map Company, Colorado Springs, CO." "Digital Orthophotography compiled by Sanborn Map Company, Colorado Springs, CO"

This product is a georectified and tonally balanced mosaic of aerial photographs collected in 1938 by the U.S. Bureau of Reclamation along the floodplain of the Colorado River in Mohave Valley, Arizona, California, and Nevada. The mosaic is provided in both GeoTIFF and MrSID file format.

In May 2021, the Grand Canyon Monitoring and Research Center (GCMRC) of the U.S. Geological Survey’s (USGS), Southwest Biological Science Center (SBSC) acquired airborne multispectral high resolution data for the Colorado River in Grand Canyon in Arizona, USA. The imagery data consist of four bands (Band 1 – red, Band 2 – green, Band 3 – blue, and Band 4 – near infrared) with a ground resolution of 20 centimeters (cm). These image data are available to the public as 16-bit GeoTIFF files, which can be read and used by most geographic information system (GIS) and image-processing software. The spatial reference of the image data are in the State Plane (SP) map projection using the central Arizona zone (FIPS 0202) and the North American Datum of 1983 (NAD83) National Adjustment of 2011 (NA2011). The airborne data acquisition was conducted under contract by Fugro Earthdata Inc (Fugro) using two fixed wing aircraft from May 29th to June 4th, 2021 at flight altitudes from approximately 2,440 to 3,350 meters above mean sea level. Fugro produced a corridor-wide mosaic using the best possible flight line images with the least amount of smear, the smallest shadow extent, and clearest, most glint-free water possible. The mosaic delivered by Fugro was then further corrected by GCMRC for smear, shadow extent and water clarity as described in the process steps of this metadata and for previous image acquisitions in Durning et al. (2016) and Davis (2012). 47 ground controls points (GCPs) were used to conduct an independent spatial accuracy assessment by GCMRC. The accuracy calculated from the GCPs is reported at 95% confidence as 0.514 m and a Root Mean Square Error (RMSE) of 0.297 m.

Maps of California's Wildland Urban Interface (WUI) generated using the Time Step Moving Window (TSMW) method outlined in the paper "Remapping California's Wildland Urban Interface: A Property-Level Time-Space Framework, 2000-2020".

Please cite the original paper:

Berg, Aleksander K, Dylan S. Connor, Peter Kedron, and Amy E. Frazier. 2024. “Remapping California’s Wildland Urban Interface: A Property-Level Time-Space Framework, 2000–2020.” Applied Geography 167 (June): 103271. https://doi.org/10.1016/j.apgeog.2024.103271.

WUI maps were generated using Zillow ZTRAX parcel level attributes joined with FEMA USA Structures building footprints and the National Land Cover Database (NLCD).

All files are geotiff rasters with WUI areas mapped at a ~30m resolution. A raster value of null indicates not WUI, raster value of 1 indicates intermix WUI, and a raster value of 2 indicates interface WUI.

Three WUI maps were generated using structures built on of before the years indicated below:

2000 - "CA_WUI_2000.tif"

2010 - "CA_WUI_2010.tif"

2020 - "CA_WUI_2020.tif"

Acknowledgments -

We thank our reviewers and editors for helping us to improve the manuscript. We gratefully acknowledge access to the Zillow Transaction and Assessment Dataset (ZTRAX) through a data use agreement between the University of Colorado Boulder, Arizona State University, and Zillow Group, Inc. More information on accessing the data can be found at http://www.zillow.com/ztrax. The results and opinions are those of the author(s) and do not reflect the position of Zillow Group. Support by Zillow Group Inc. is acknowledged. We thank Johannes Uhl and Stefan Leyk for their great work in preparing the original dataset. For feedback and comments, we also thank Billie Lee Turner II, Sharmistha Bagchi-Sen, and participants at the 2022 Global Conference on Economic Geography, the 2022 Young Economic Geographers Network meeting, and the 2023 annual meeting of the American Association of Geographers. Funding for our work has been provided by Arizona State University's Institute of Social Science Research (ISSR) Seed Grant Initiative. Additional funding was provided through the Humans, Disasters, and the Built Environment program of the National Science Foundation, Award Number 1924670 to the University of Colorado Boulder, the Institute of Behavioral Science, Earth Lab, the Cooperative Institute for Research in Environmental Sciences, the Grand Challenge Initiative and the Innovative Seed Grant program at the University of Colorado Boulder as well as the Eunice Kennedy Shriver National Institute of Child Health & Human Development of the National Institutes of Health under Award Numbers R21 HD098717 01A1 and P2CHD066613.

Citation: Manley, W.F., Parrish, E.G., and Lestak, L.R., 2009, High-Resolution Orthorectified Imagery and Digital Elevation Models for Study of Environmental Change at Niwot Ridge and Green Lakes Valley, Colorado: Niwot Ridge LTER, INSTAAR, University of Colorado at Boulder, digital media. This image is a mosaic of orthorectified aerial photography from 1988 and 1990 for the Niwot Ridge Long Term Ecological Research (LTER) project area at 0.6 m resolution. The image also covers the Green Lakes Valley portion of the Boulder Creek Critical Zone Observatory (CZO). The mosaic has the qualities of a photograph and the functionality of a map layer for use in Geographic Information Systems (GIS) or remote sensing software. The mosaic is derived from approx. 1:40,000 scale, color infrared (CIR) photographs acquired by the United States Geological Survery (USGS) National Aerial Photography Program (NAPP). The aerial photos were obtained as 1800 dpi digital scans from the USGS EROS Data Center (EDC) and then fully orthorectified in a Leica Photogrammetry Suite (LPS) bundle blockfile using an air-photo camera model, a Digital Elevation Model (DEM), and known focal length and fiducial coordinates from a calibration report. Individual photo frames were mosaiced with cutlines and clipped to the Niwot project extent area. The photography was registered to 2008 orthocorrected Denver Region Council of Governments (DRCOG) aerial photography. Horizontal accuracy is 0.9 m (RMSE, relative to the 2008 reference imagery, based on 9 independent check points). The mosaic covers an area of 98 km2 and is available in GeoTIFF format, in a UTM zone 13 projection and NAD83 horizontal datum, with FGDC-compliant metadata. The mosaic is available through an unrestricted public license, and can be obtained by request (see Distributor contact information below). Other datasets available in this series includes orthorectified aerial photograph mosaics (for 1953, 1972, 1985, 1999, 2000, 2002, 2004, 2006 and 2008), digital elevation models (DEM's), and accessory map layers. Together, the DEM's and imagery will be of interest to students, research scientists, and others for observation and analysis of natural features and ecosystems. NOTE: This EML metadata file does not contain important geospatial data processing information. Before using any NWT LTER geospatial data read the arcgis metadata XML file in either ISO or FGDC compliant format, using ArcGIS software (ArcCatalog > description), or by viewing the .xml file provided with the geospatial dataset.

This directory contains vector and raster data for a lesson on automation with Make (https://github.com/earthlab-education/ea-applications-make-tutorial). The automated process is a zonal statistics analysis that can be executed using point or polygon data. The polygon vector data is a shapefile of Boulder County, Colorado from the Colorado Department of Public Health and Environment open data portal. The raster data is a GeoTIFF of the National Land Cover Database for 2011 cropped to Boulder County, Colorado. The point vector data are 50 evenly spaced sample points across the GeoTIFF, including the nodata/mask area.

Loudoun County annually obtains leaf-off, aerial imagery in the spring. Since 2004, the County has utilized this imagery to support the development of an annual digital orthophoto base. In 2023, the imagery was captured with a Vexcel Ultracam Eagle digital camera, in 4-band (R,G,B, and NIR) format. These files contain 1-foot ground-resolution, 8-bit, 4-band orthorectified aerial image map products in GeoTIFF version 6.0 file format. GeoTIFF files are uncompressed raster images complete with TFW coordinate information. The aerial imagery project encompasses the entire land area of the County of Loudoun, VA. Images were flown during leaf-off conditions and cover 5000' by 5000' and are tiled according to the VBMP 200-scale gridding schema (Virginia Geographic Information Network)."March 2023 Photography flown by The Sanborn Map Company, Inc. Colorado Springs, CO." "Digital Orthophotography compiled by Sanborn Map Company, Inc. Colorado Springs, CO"

High-resolution geophysical mapping of Lake Powell in the Glen Canyon National Recreation Area in Utah and Arizona was conducted between October 8 and November 15, 2017, as part of a collaborative effort between the U.S. Geological Survey and the Bureau of Reclamation to provide high-quality data needed to reassess the area-capacity tables for the Lake Powell reservoir. Seismic data collected during this survey can help to define the rates of deposition within the San Juan and Colorado Rivers, which are the main inflows to Lake Powell. These new data are intended to improve water budget management decisions that affect the natural and recreational resources of the reservoir. Multibeam echosounder bathymetry and backscatter data were collected along 2,312 kilometers of tracklines (331 square kilometers) of the lake floor to regionally define its depth and morphology, as well as the character and distribution of lake-floor sediments. Ninety-two kilometers of seismic-reflection profile data were also collected to define the thickness and structure of sediment deposits near the confluences of the San Juan and Colorado Rivers.

description: 2010 Boulder Creek, Colorado Snow-Off Lidar SurveysLidar was acquired for a 600 km2 area inside the Boulder Creek watershed during a snow-off (August, 2010) time slice, near Boulder Colorado. This data was collected in collaboration between the National Center for Airborne Laser Mapping (NCALM) project and the Boulder Creek Critical Zone Observatory (CZO), both funded by the National Science Foundation (NSF). The dataset contains 1 m Digital Surface Models (first-stop), Digital Terrain Models (bare-earth), and 10 points/m2 LAS-formated point cloud tiles. The DSMs and DTMs are available in GeoTIFF format, approx. 1-2 GB each, with associated shaded relief models, for a total of 15 GB of data. The Digital Terrain Model (DTM) is a ground-surface elevation dataset better suited for derived layers such as slope angle, aspect, and contours. Accessory layers consist of index map layers for point cloud tiles, DEM extent, and flight lines. Other Lidar DSMs, DTMs, and point cloud data available in this series include snow-on data for 2010. Together, the Lidar Digital Elevation Models (DEM) and point cloud data will be of interest to land managers, scientists, and others for study of topography, snow, ecosystems and environmental change. The Boulder Creek CZO will be using the Lidar data to further their mission of focusing on how water, atmosphere, ecosystems, & soils interact and shape the Earth's surface. The "Critical Zone" lies between rock and sky. It is essential to life - including human food production - and helps drive Earth's carbon cycle, climate change, stream runoff, and water quality.PLEASE READ the FGDC-compliant metadata files that are available for each dataset (in .html, .txt, and .xml formats). These files provide numerous details that may be of interest. The Boulder Creek CZO provides access to precomputed DEMs and hillshades for this dataset here.; abstract: 2010 Boulder Creek, Colorado Snow-Off Lidar SurveysLidar was acquired for a 600 km2 area inside the Boulder Creek watershed during a snow-off (August, 2010) time slice, near Boulder Colorado. This data was collected in collaboration between the National Center for Airborne Laser Mapping (NCALM) project and the Boulder Creek Critical Zone Observatory (CZO), both funded by the National Science Foundation (NSF). The dataset contains 1 m Digital Surface Models (first-stop), Digital Terrain Models (bare-earth), and 10 points/m2 LAS-formated point cloud tiles. The DSMs and DTMs are available in GeoTIFF format, approx. 1-2 GB each, with associated shaded relief models, for a total of 15 GB of data. The Digital Terrain Model (DTM) is a ground-surface elevation dataset better suited for derived layers such as slope angle, aspect, and contours. Accessory layers consist of index map layers for point cloud tiles, DEM extent, and flight lines. Other Lidar DSMs, DTMs, and point cloud data available in this series include snow-on data for 2010. Together, the Lidar Digital Elevation Models (DEM) and point cloud data will be of interest to land managers, scientists, and others for study of topography, snow, ecosystems and environmental change. The Boulder Creek CZO will be using the Lidar data to further their mission of focusing on how water, atmosphere, ecosystems, & soils interact and shape the Earth's surface. The "Critical Zone" lies between rock and sky. It is essential to life - including human food production - and helps drive Earth's carbon cycle, climate change, stream runoff, and water quality.PLEASE READ the FGDC-compliant metadata files that are available for each dataset (in .html, .txt, and .xml formats). These files provide numerous details that may be of interest. The Boulder Creek CZO provides access to precomputed DEMs and hillshades for this dataset here.

Link to the ScienceBase Item Summary page for the item described by this metadata record. Service Protocol: Link to the ScienceBase Item Summary page for the item described by this metadata record. Application Profile: Web Browser. Link Function: information

This image is a mosaic of orthorectified aerial photography from 1988 and 1990 for the Niwot Ridge Long Term Ecological Research (LTER) project area at 0.6 m resolution. The image also covers the Green Lakes Valley portion of the Boulder Creek Critical Zone Observatory (CZO). The mosaic has the qualities of a photograph and the functionality of a map layer for use in Geographic Information Systems (GIS) or remote sensing software. The mosaic is derived from approx. 1:40,000 scale, color infrared (CIR) photographs acquired by the United States Geological Survery (USGS) National Aerial Photography Program (NAPP). The aerial photos were obtained as 1800 dpi digital scans from the USGS EROS Data Center (EDC) and then fully orthorectified in a Leica Photogrammetry Suite (LPS) bundle blockfile using an air-photo camera model, a Digital Elevation Model (DEM), and known focal length and fiducial coordinates from a calibration report. Individual photo frames were mosaiced with cutlines and clipped to the Niwot project extent area. The photography was registered to 2008 orthocorrected Denver Region Council of Governments (DRCOG) aerial photography. Horizontal accuracy is 0.9 m (RMSE, relative to the 2008 reference imagery, based on 9 independent check points). The mosaic covers an area of 98 km2 and is available in GeoTIFF format, in a UTM zone 13 projection and NAD83 horizontal datum, with FGDC-compliant metadata. The mosaic is available through an unrestricted public license, and can be obtained by request (see Distributor contact information below). Other datasets available in this series includes orthorectified aerial photograph mosaics (for 1953, 1972, 1985, 1999, 2000, 2002, 2004, 2006 and 2008), digital elevation models (DEM's), and accessory map layers. Together, the DEM's and imagery will be of interest to students, research scientists, and others for observation and analysis of natural features and ecosystems. NOTE: This EML metadata file does not contain important geospatial data processing information. Before using any NWT LTER geospatial data read the arcgis metadata XML file in either ISO or FGDC compliant format, using ArcGIS software (ArcCatalog > description), or by viewing the .xml file provided with the geospatial dataset.

(SEE SUPPLEMENTAL INFORMATION SECTION FOR FILE-SPECIFIC INFORMATION.)Digital orthophoto quarter-quads are now available for most of the United States and its Territories. Quarter-quad DOQs cover an area measuring 3.75-minutes longitude by 3.75-minutes latitude. Quarter-quad DOQs are available in both Native and GeoTIFF formats. Native format consists of an ASCII keyword header followed by a series of 8-bit binary image lines for B/W and 24-bit band-interleaved-by-pixel (BIP) for color. DOQs in native format are cast to the Universal Transverse Mercator (UTM) projection and referenced to either the North American Datum (NAD) of 1927 (NAD27) or the NAD of 1983 (NAD83). GeoTIFF format consists of a georeferenced Tagged Image File Format (TIFF), with all geographic referencing information embedded within the .tif file. DOQs in GeoTIFF format are cast to the UTM projection and referenced to NAD83. The average file size of a B/W quarter quad is 40-45 megabytes, and a color file is generally 140-150 megabytes. Quarter-quad DOQs are distributed on CD-ROM, DVD, and File Transfer Protocol (FTP) as uncompressed files.A downloadable software is available (DOQQ-to-GeoTIFF conversion) which will convert a DOQ image from Native to GeoTIFF format in either NAD27 or NAD83. NOTE: This EML metadata file does not contain important geospatial data processing information. Before using any NWT LTER geospatial data read the arcgis metadata XML file in either ISO or FGDC compliant format, using ArcGIS software (ArcCatalog > description), or by viewing the .xml file provided with the geospatial dataset.

Loudoun County annually obtains leaf-off, aerial imagery in the spring. Since 2004, the County has utilized this imagery to support the development of an annual digital orthophoto base. In 2022, the imagery was captured with a Vexcel Ultracam Eagle digital camera, in 4-band (R,G,B, and NIR) format. These files contain 1-foot ground-resolution, 8-bit, 4-band orthorectified aerial image map products in GeoTIFF version 6.0 file format. GeoTIFF files are uncompressed raster images complete with TFW coordinate information. The aerial imagery project encompasses the entire land area of the County of Loudoun, VA. Images were flown during leaf-off conditions and cover 5000' by 5000' and are tiled according to the VBMP 200-scale gridding schema (Virginia Geographic Information Network)."February 2022 Photography flown by the Sanborn Map Company, Colorado Springs, CO." "Digital Orthophotography compiled by Sanborn Map Company, Colorado Springs, CO"