Identification_Information: Citation: Citation_Information: Originator: Wolken, G.J. Originator: Wikstrom Jones, Katreen Originator: Whorton, E.N. Originator: Gould, A.I. Originator: Hendricks, M.D. Publication_Date: 2017 Title: Photogrammetric data of the Haines Highway corridor: May 26, 2014 Geospatial_Data_Presentation_Form: imagery Series_Information: Series_Name: Raw Data File Issue_Identification: RDF 2017-6 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 20 p. Online_Linkage: http://doi.org/10.14509/29736 Description: Abstract: The State of Alaska Division of Geological & Geophysical Surveys (DGGS) produced an orthorectified aerial optical image mosaic (orthoimage) and digital surface model over an area extending from milepost (MP) 17 to approximately MP 24.5 on the Alaska State Highway 7 (Haines Highway) north of Haines along the Chilkat River in southeast Alaska. The aerial photogrammetric survey targeted large debris fans and their alpine source areas on the west side of the Takshanuk Mountains in support of cryosphere hazards mapping and monitoring efforts. Aerial photographs and Global Navigation Satellite System (GNSS) data were collected on May 26, 2014, and were processed using Structure-from-Motion (SfM) photogrammetric techniques to create the orthoimagery. For the purpose of enabling open access to geospatial datasets in Alaska, this collection is being released as a Raw Data File with an open end-user license. The data files available for download are tiled GeoTIFFs. All data are projected in UTM Zone 8 North (meters) using the NAD83 (2011; EPSG 6337) horizontal datum and NAVD88 (Geoid12A; EPOCH 2010.00) vertical datum. Purpose: In 2014, the Alaska Division of Geological & Geophysical Surveys (DGGS) began a collaborative study with the Alaska Department of Transportation & Public Facilities (DOT&PF) along the Haines Highway corridor near Haines, Alaska. The intent of this study is to evaluate, monitor, and model geophysical processes, including cryosphere-related changes, along this important transportation corridor where destructive debris flows regularly impact the highway by threatening motorists, damaging infrastructure, and impeding traffic flow. Repeat aerial photography and digital surface model (DSM) generation of this dynamic catchment is the first step to allow DGGS to quantify debris volumes, understand the source of the debris flows, and provide guidance to DOT&PF planners for mitigating the hazard to the roadway. Supplemental_Information: >digital surface model: DSMs represent surface elevations of all surfaces, including vegetation, vegetation-free land, bridges, buildings, etc. The DSM is a single-band, 32-bit float GeoTIFF file using Lempel-Ziv-Welch (LZW) compression, with a ground sample distance (GSD) of 0.21 m. "No Data" value is set to -32767. >orthoimage: The orthoimage is a three-band, 8-bit unsigned GeoTIFF file using LZW compression. The orthoimage has a GSD of 0.21 m per pixel, and the "No Data" value is set to 0. Variable lighting in the orthoimages may result from variable sky conditions during the time of data acquisition. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2014 Currentness_Reference: ground condition Status: Progress: complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -135.963385 East_Bounding_Coordinate: -135.746471 North_Bounding_Coordinate: 59.455425 South_Bounding_Coordinate: 59.342360 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Theme_Keyword: Aerial Theme_Keyword: Debris Flow Theme_Keyword: Engineering Theme_Keyword: Engineering Geology Theme_Keyword: Environmental Theme_Keyword: Geologic Hazards Theme_Keyword: Geology Theme_Keyword: Geomorphology Theme_Keyword: Hazards Theme_Keyword: Methods Theme_Keyword: Orthoimagery Theme_Keyword: Raster Image Theme_Keyword: Slope Theme_Keyword: Surface Theme_Keyword: Surficial Place: Place_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Place_Keyword: Alaska, State of Place_Keyword: Chilkat River Place_Keyword: Haines Place_Keyword: Klukwan Place_Keyword: Southeast Alaska Place_Keyword: Takshanuk Mountains Temporal: Temporal_Keyword_Thesaurus: Walker, J.D., Geissman, J.W., Bowring, S.A, and Babcock, L.E., comp., 2012, Geologic Time Scale v. 4.0: Geological Society of America Temporal_Keyword: Holocene Access_Constraints: This report, map, and/or dataset is available directly from the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (see contact information below). Use_Constraints: Any hard copies or published datasets utilizing these datasets shall clearly indicate their source. If the user has modified the data in any way, the user is obligated to describe the types of modifications the user has made. The user specifically agrees not to misrepresent these datasets, nor to imply that changes made by the user were approved by the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys. The State of Alaska makes no express or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Position: Metadata Manager Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: (907)451-5039 Contact_Facsimile_Telephone: (907)451-5050 Contact_Electronic_Mail_Address: dggspubs@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Data_Set_Credit: This project is funded by the State of Alaska Department of Transportation & Public Facilities and a State of Alaska Capital Improvement Project. Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: DSMs represent surface elevations of all surfaces, including vegetation, vegetation-free land, bridges, buildings, etc. The DSM is a single-band, 32-bit float GeoTIFF file using Lempel-Ziv-Welch (LZW) compression, with a ground sample distance (GSD) of 0.21 m. "No Data" value is set to -32767. The orthoimage is a three-band, 8-bit unsigned GeoTIFF file using LZW compression. The orthoimage has a GSD of 0.21 m per pixel, and the "No Data" value is set to 0. Variable lighting in the orthoimages may result from variable sky conditions during the time of data acquisition. Logical_Consistency_Report: The aerial photography survey was planned so flight lines and photograph frequency provided 60 percent side lap and 80 percent end lap coverage, with an average above-ground-level flying height of 1341 m, resulting in 872 photos with 0.21 m ground sample distance (GSD). Ground-based GNSS surveys of stable, photo-identifiable ground control points (GCPs) and check points were conducted by DGGS scientists between fall 2014 and fall 2015 utilizing identical GNSS Topcon HiPer II rover and base units. Completeness_Report: This data release is complete. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Horizontal accuracy of the DSM was assessed by comparing the locations of ten checkpoints to the same point in the co-registered orthoimagery. The mean offset (residual) was -0.14 m in the X-direction and -0.02 m in the Y-direction, with a standard deviation of 0.29 (0.20, Y-direction) and a root-mean-square error (RMSE) of 0.31 (0.27, Y-direction). No horizontal transformation was applied because horizontal offsets were not identified at or above the pixel scale (i.e., 0.21 m GSD). Horizontal accuracy of the orthoimagery was assessed by comparing the locations of ten checkpoints to the same point in the orthoimagery (fig. 3). The mean offset (residual) was -0.14 m in the X-direction and -0.02 m in the Y-direction, with a standard deviation of 0.29 (0.20, Y-direction) and a root-mean-square error (RMSE) of 0.31 (0.27, Y-direction). No horizontal transformation was applied because horizontal offsets were not identified at or above the pixel scale (i.e., 0.21 m GSD). See accompanying report for additional detail. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: Vertical accuracies of the DSM were evaluated by comparing the elevation values of ten checkpoints to the elevation values at the same location in the DSM. The mean vertical offset was -0.09 m with a standard deviation of 0.24 m and an RMSE of 0.25 (Table 1 of the accompanying report). Lineage: Process_Step: Process_Description: Data acquisition - The State of Alaska Division of Geological & Geophysical Surveys contracted Fairbanks Airborne Remote Sensing to collect digital aerial photographic data on May 26, 2014, using a fixed-wing (Cessna 180) airborne platform. The aerial photography survey was planned so flight lines and photograph frequency provided 60 percent side lap and 80 percent end lap coverage, with an average above-ground-level flying height of 1341 m, resulting in 872 photos with 0.21 m ground sample distance (GSD). The total area surveyed was 106.9 km2. A Nikon D800 camera with AF-Nikkor 28mm f/2.8D lens was used to collect 36.2-megapixel JPEG photographs (7360 x 4912 pixels per image) which were compressed for optimal quality. During the aerial survey, the photograph center coordinates were determined using a custom intervalometer that linked the camera shutter release with Global Positioning System (GPS) event markers created by an onboard Trimble 5700 receiver and a dual-band Novatel roof-mounted antenna approximately 1 m above the camera, with a background sampling frequency of 5 Hz. A GPS base station with a Trimble 5700 receiver and a Zephyr antenna sampling at 1 Hz was placed approximately 100 km from the survey area, and was used to differentially correct the aerial survey GPS data using post-processing kinematic (PPK) methods. Ground-based GNSS surveys of stable, photo-identifiable ground control points (GCPs) and check points were conducted by DGGS scientists between fall 2014 and fall 2015 utilizing identical GNSS Topcon HiPer II rover and base units. Process_Date: 2014 Process_Step: Process_Description: GNSS data processing - Aerial survey GNSS data were processed by DGGS using PPK methods in Topcon Positioning Systems, Inc., Magnet Office Tools commercial GNSS software. The HiPer II base station position was corrected using the National Geodetic Survey OPUS with the IGS08 (EPOCH: 2014.7342) solution. The base station was used as the vertical and horizontal control. GNSS data were collected and processed in WGS84 (G1674) using the WGS84 ellipsoid. The National Geodetic Survey VDatum tool was used to transform GNSS data to the North American Datum 1983 (NAD83; 2011) European Petroleum Survey Group Well Known Identification Number (EPSG) 6337 and the North American Vertical Datum of 1988 (NAVD88; Geoid12A; EPOCH 2010.00). The coordinates are projected in UTM Zone 8 North and are in meters. Aerial survey GNSS data (event marker coordinates) were manually correlated to each image using the image timestamp to create a camera exterior orientation file for import into the photogrammetric software. The exterior orientation file provides the X, Y, Z position of the camera for each photograph taken during the survey. Yaw, pitch, and roll information were not recorded during the flight. GCPs and checkpoints were differentially corrected using PPK and static methods with respect to an existing benchmark at the Haines airport (HNS D; PID: AI4905). Process_Date: 2015 Process_Step: Process_Description: Photogrammetry - Aerial stereo-photographs were imported into the commercially-available Agisoft Photoscan Professional software. This photogrammetric software uses a SfM algorithm to identify matching pixels in overlapping photographs and triangulate their common ground position to create a 3-dimensional point cloud (x, y, z coordinates) that defines the ground surface. Specifically, Photoscan was used to align the aerial photographs, edit the sparse point cloud, optimize the bundle adjustment, construct the dense point cloud, build a DSM, and export tiled DSM GeoTIFFs. Process_Date: 2015 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: raster Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 8 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -135 Latitude_of_Projection_Origin: 0 False_Easting: 500000.000000 False_Northing: 0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: .00000001 Ordinate_Resolution: .00000001 Planar_Distance_Units: Meters Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1983 Ellipsoid_Name: GRS 80 Semi-major_Axis: 6378137 Denominator_of_Flattening_Ratio: 298.257222101000025 Vertical_Coordinate_System_Definition: Altitude_System_Definition: Altitude_Datum_Name: NAVD88; Geoid12A; EPOCH 2010.00 Altitude_Resolution: 0.21 Altitude_Distance_Units: meters Altitude_Encoding_Method: Implicit coordinate Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Attribute_Layer_Name: digital surface model Entity_Type_Label: digital surface model Entity_Type_Definition: DSMs represent surface elevations of all surfaces, including vegetation, vegetation-free land, bridges, buildings, etc. The DSM is a single-band, 32-bit float GeoTIFF file using Lempel-Ziv-Welch (LZW) compression, with a ground sample distance (GSD) of 0.21 m. "No Data" value is set to -32767. File format: GeoTIFF. Entity_Type_Definition_Source: Alaska Division of Geological & Geophysical Surveys (DGGS) and Fairbanks Airborne Remote Sensing Detailed_Description: Entity_Type: Entity_Attribute_Layer_Name: orthoimage Entity_Type_Label: orthoimage Entity_Type_Definition: The orthoimage is a three-band, 8-bit unsigned GeoTIFF file using LZW compression. The orthoimage has a GSD of 0.21 m per pixel, and the "No Data" value is set to 0. Variable lighting in the orthoimages may result from variable sky conditions during the time of data acquisition. File format: GeoTIFF. Entity_Type_Definition_Source: Alaska Division of Geological & Geophysical Surveys (DGGS) and Fairbanks Airborne Remote Sensing Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Position: Metadata Manager Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: (907)451-5039 Contact_Facsimile_Telephone: (907)451-5050 Contact_Electronic_Mail_Address: dggspubs@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Resource_Description: RDF 2017-6 Distribution_Liability: The State of Alaska makes no expressed or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product. Standard_Order_Process: Non-digital_Form: DGGS publications are available as free online downloads or you may purchase paper hard-copies or digital files on CD/DVD or other digital storage media by mail, phone, fax, or email from the DGGS Fairbanks office. To purchase this or other printed reports and maps, contact DGGS by phone (907-451-5020), e-mail (dggspubs@alaska.gov), or fax (907-451-5050). Payment accepted: Cash, check, money order, VISA, or MasterCard. Turnaround time is 1-2 weeks unless special arrangements are made and an express fee is paid. Shipping charge will be the actual cost of postage and will be added to the total amount due. Contact us for the exact shipping amount. Fees: Contact DGGS for current pricing Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: imagery Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://doi.org/10.14509/29736 Fees: Free download Metadata_Reference_Information: Metadata_Date: 20170807 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Position: Metadata Manager Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: (907)451-5039 Contact_Facsimile_Telephone: (907)451-5050 Contact_Electronic_Mail_Address: dggspubs@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Use_Constraints: If the user has modified the data in any way they are obligated to describe the types of modifications they have performed in the supporting metadata file. User specifically agrees not to imply that changes they made were approved by the Alaska Department of Natural Resources or Division of Geological & Geophysical Surveys. Metadata_Extensions: Online_Linkage: http://www.dggs.alaska.gov/metadata/dggs.ext Profile_Name: dggs metadata extensions