Identification_Information: Citation: Citation_Information: Originator: Wikstrom Jones, K.M. Originator: Wolken, G.J. Originator: Daanen, R.P. Publication_Date: 2023 Title: Lidar-derived elevation data for Columbia Glacier terminus and adjacent slope, Southcentral Alaska, collected September 18, 2022 Geospatial_Data_Presentation_Form: data Series_Information: Series_Name: Raw Data File Issue_Identification: RDF 2023-16 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 11 p. Online_Linkage: https://doi.org/10.14509/31032 Description: Abstract: Lidar-derived elevation data for Columbia Glacier terminus and adjacent slope, Southcentral Alaska, collected September 18, 2022, Raw Data File 2023-16, provides an aerial lidar derived classified point cloud, a digital terrain model (DTM), and an intensity model of the unstable slope at the terminus of Columbia Glacier, located in Prince William Sound in Southcentral Alaska. Aerial and ground control data were collected on September 18, 2022, and subsequently processed in a suite of geospatial processing software. These data support a paraglacial rock slope destabilization study at Columbia Glacier and will be used to assess and characterize an ongoing landslide hazard. All files can be downloaded from the Alaska Division of Geological & Geophysical Surveys website (http://doi.org/10.14509/31032). Purpose: These data support a paraglacial rock slope destabilization study at Columbia Glacier and will be used to assess and characterize an ongoing landslide hazard. Supplemental_Information: >boundaries: A boundary, also known as an Area of Interest (AOI) or border, that defines the area covered by the data. also includes footprints for tiled data. >classified_points: Classified point cloud data are provided in compressed LAZ format. This dataset only includes ground points and unclassified points; low- and high-noise points are excluded. Potential vegetation points remain within the unclassified points class. For classified ground points, the average point density is 13.9 points/m2. >dtm: The DTM represents bare earth elevations, excluding vegetation, bridges, buildings, etc. The DTM is a single-band, 32-bit float GeoTIFF file of 0.20-meter resolution. No Data value is set to -3.40282306074e+38. >lidar_intensity: The lidar intensity image describes the relative amplitude of reflected signals contributing to the point cloud. Lidar intensity is largely a function of scanned object reflectance in relation to the signal frequency, is dependent on ambient conditions, and is not necessarily consistent between separate scans. The intensity image is a single-band, 32-bit float GeoTIFF file of 0.5-meter resolution. No Data value is set to -3.40282306074e+38. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 20220922 Currentness_Reference: ground condition Status: Progress: complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -147.040293 East_Bounding_Coordinate: -146.921476 North_Bounding_Coordinate: 61.226991 South_Bounding_Coordinate: 61.177871 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: Coastal Theme_Keyword: Coastal and River Theme_Keyword: DGGS Theme_Keyword: Digital Elevation Model Theme_Keyword: Digital Terrain Model Theme_Keyword: Elevation Theme_Keyword: Emergency Preparedness Theme_Keyword: Engineering Theme_Keyword: Engineering Geology Theme_Keyword: Environmental Theme_Keyword: Geologic Theme_Keyword: Geologic Hazards Theme_Keyword: Geological Process Theme_Keyword: Geology Theme_Keyword: Geomorphology Theme_Keyword: Geophysics Theme_Keyword: Geotechnical Theme_Keyword: Glacial Theme_Keyword: Glacial Deposits Theme_Keyword: Glacial Geology Theme_Keyword: Glacial Geomorphology Theme_Keyword: Glacial Processes Theme_Keyword: Glaciers Theme_Keyword: Glaciology Theme_Keyword: Hazards Theme_Keyword: Hydrology and Surficial Geology Theme_Keyword: Landslide Theme_Keyword: LiDAR Theme_Keyword: LiDAR Intensity Image Theme_Keyword: LiDAR LAS File Format Theme_Keyword: Periglacial Slope Failure Theme_Keyword: Point Cloud Data Theme_Keyword: Point Count Theme_Keyword: Raster Image Theme_Keyword: Remote Sensing Theme_Keyword: Rock Avalanche Theme_Keyword: Rockfall Theme_Keyword: Slope Theme_Keyword: Slope Instability Theme_Keyword: Surface Theme_Keyword: Surficial Theme_Keyword: Surficial Geology Theme_Keyword: Topography Theme_Keyword: Unconsolidated Deposits Theme_Keyword: Water Place: Place_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Place_Keyword: Columbia Bay Place_Keyword: Columbia Glacier Place_Keyword: Prince William Sound Place_Keyword: Southcentral Alaska 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)451-5020 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 Contact_Instructions: Please view our website (https://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible. Data_Set_Credit: These data products were funded by a U.S. Geological Survey Cooperative Agreement (Grant Number G21AC10362-00) and the State of Alaska and collected and processed by DGGS. We thank Clearwater Air for their aviation expertise and contribution to these data products. The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Government. Cross_Reference: Citation_Information: Originator: Stevens, D.S.P. Originator: Wolken, G.J. Originator: Hubbard, T.D. Originator: Hendricks, K.A. Publication_Date: 2018 Title: Landslides in Alaska Series_Information: Series_Name: Information Circular Issue_Identification: IC 65 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 2 p Online_Linkage: https://doi.org/10.14509/29849 Cross_Reference: Citation_Information: Originator: Timm, Kristin Originator: Wolken, G.J. Publication_Date: 2017 Title: Deglacierization and the development of glacier-related hazards Series_Information: Series_Name: Information Circular Issue_Identification: IC 63 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 3 p Online_Linkage: https://doi.org/10.14509/29752 Cross_Reference: Citation_Information: Originator: Wolken, G.J. Originator: Hendricks, K.A. Originator: Daanen, R.P. Originator: Overbeck, J.R. Originator: Stevens, D.S.P. Originator: Masterman, S.S. Publication_Date: 2017 Title: Alaska & climate change Series_Information: Series_Name: Information Circular Issue_Identification: IC 64 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 2 p Online_Linkage: https://doi.org/10.14509/29781 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Not applicable Logical_Consistency_Report: This publication is a complete release dataset. There was no over-collect except for aircraft turns that were eliminated from the dataset. The data quality is consistent throughout the survey. Completeness_Report: This data relaease is complete. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: We did not measure horizontal accuracy for this collection. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: A mean vertical offset of 19.8 cm was measured between 64 control points and the point cloud. A final accuracy of -6.4 cm was achieved by performing a vertical transformation of the lidar point data. Eighteen check points were used to determine the non-vegetated vertical accuracy of the point cloud ground class, using a Triangulated Irregular Network (TIN)-based approach, and a root mean square error (RMSE) of 13.4 cm was achieved. We evaluated the relative accuracy for this dataset as the interswath overlap consistency and measured it at 1.9 cm RMSE. Lineage: Process_Step: Process_Description: Ground survey - Ground control and check points were collected on September 18, 2022. We deployed a Trimble R10-2 GNSS receiver with an internal antenna at a temporary benchmark at a centralized location within the survey area (61 degrees 12 minutes 37.84428 seconds N; 146 degrees 57 minutes 58.96235 seconds W). It provided a base station occupation and real-time kinematic (RTK) corrections to points we surveyed with a rover Trimble R10-2 GNSS receiver (internal antenna). A total of 82 ground control and check points were collected to use for calibration and to assess the vertical accuracy of the point cloud. All points were collected on bare earth. Process_Date: 20220918 Process_Step: Process_Description: Aerial survey - DGGS used a Riegl VUX1-LR laser scanner integrated with a global navigation satellite system (GNSS) and Northrop Grumman LN-200C inertial measurement unit (IMU). The lidar integration system was designed by Phoenix LiDAR Systems. The sensor can collect up to 820,000 points per second at a range of up to 150 m. The scanner operated with a pulse repetition rate of 100,000-400,000 pulses per second at a scan rate between 80 and 160 revolutions per second. We used a Cessna 180 fixed-wing platform to survey from an elevation of about 100-500 m above ground level, at a ground speed of ~37 m/s, and with a scan angle set from 80 to 280 degrees. The total survey area covers ~14 km2. We flew the aerial survey on September 18, 2022, beginning at 10:21 am and ending at 11:57 am (AKDT). The weather throughout the survey was clear, with still winds. Process_Date: 20220918 Process_Step: Process_Description: Lidar dataset processing - The point data were processed in SDCimport software for initial filtering and multiple-time-around (MTA) disambiguation. MTA errors, corrected in this process, result from ambiguous interpretations of received pulse time intervals and occur more frequently with higher pulse refresh rates. The IMU and GNSS data were processed in Inertial Explorer, and Spatial Explorer software was used to integrate flightline information with the point cloud. We calibrated the point data at an incrementally precise scale of sensor movement and behavior, incorporating sensor velocity, roll, pitch, and yaw fluctuations throughout the survey. For the lidar data collection, the average nominal point density is 31.4 points/m2 and the average nominal pulse spacing is 17.9 cm. We created macros in Terrasolid software and classified points in accordance with the American Society for Photogrammetry and Remote Sensing (ASPRS) 2019 guidelines. Once classified, we applied a geometric transformation and converted the points from ellipsoidal heights to GEOID12B (Alaska) orthometric heights. ArcGIS Pro was used to derive raster products from the point cloud. The 0.20-meter DTM was interpolated from all ground class returns using a triangulated-irregular network (TIN) method and minimum values. In ArcGIS Pro, we produced a 0.5-meter intensity image by binning and averaging ground and unclassified points, which include vegetation points. Process_Date: 2023 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: 6 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -147 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: NAD83 (2011) Ellipsoid_Name: GRS 80 Semi-major_Axis: 6378137 Denominator_of_Flattening_Ratio: 298.257222101 Vertical_Coordinate_System_Definition: Altitude_System_Definition: Altitude_Datum_Name: NAVD88, GEOID12B Altitude_Resolution: 0.001 Altitude_Distance_Units: meters Altitude_Encoding_Method: Explicit elevation coordinate included with horizontal coordinates Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: boundaries Entity_Type_Definition: A boundary, also known as an Area of Interest (AOI) or border, that defines the area covered by the data. also includes footprints for tiled data. Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: boundaries Detailed_Description: Entity_Type: Entity_Type_Label: classified_points Entity_Type_Definition: Classified point cloud data are provided in compressed LAZ format. This dataset only includes ground points and unclassified points; low- and high-noise points are excluded. Potential vegetation points remain within the unclassified points class. For classified ground points, the average point density is 13.9 points/m2. Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: classified_points Detailed_Description: Entity_Type: Entity_Type_Label: dtm Entity_Type_Definition: The DTM represents bare earth elevations, excluding vegetation, bridges, buildings, etc. The DTM is a single-band, 32-bit float GeoTIFF file of 0.20-meter resolution. No Data value is set to -3.40282306074e+38. Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: dtm Detailed_Description: Entity_Type: Entity_Type_Label: lidar_intensity Entity_Type_Definition: The lidar intensity image describes the relative amplitude of reflected signals contributing to the point cloud. Lidar intensity is largely a function of scanned object reflectance in relation to the signal frequency, is dependent on ambient conditions, and is not necessarily consistent between separate scans. The intensity image is a single-band, 32-bit float GeoTIFF file of 0.5-meter resolution. No Data value is set to -3.40282306074e+38. Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: lidar_intensity 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)451-5020 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 Contact_Instructions: Please view our website (https://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible. Resource_Description: RDF 2023-16 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: data Format_Version_Date: 20240208 Format_Information_Content: boundaries, classified points, dtm and lidar intensity Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://doi.org/10.14509/31032 Fees: Free download Metadata_Reference_Information: Metadata_Date: 20240208 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Person: Simone Montayne 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)451-5020 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: https://dggs.alaska.gov/metadata/dggs.ext Profile_Name: dggs metadata extensions