2021 AK DGGS Lidar: Tuntutuliak, AK
Data Set (DS) | OCM Partners (OCMP)GUID: gov.noaa.nmfs.inport:72102 | Updated: March 6, 2024 | Published / External
Summary
Short Citation
OCM Partners, 2024: 2021 AK DGGS Lidar: Tuntutuliak, AK, https://www.fisheries.noaa.gov/inport/item/72102.
Full Citation Examples
Lidar-derived elevation data for Tuntutuliak, Southwest Alaska, collected August 18, 2021, Raw Data File 2023-17, provides aerial lidar derived classified point cloud data, a digital surface model (DSM), a digital terrain model (DTM), and an intensity model of Tuntutuliak, Southwest Alaska. Data were collected during leaf-on ground conditions. The survey provides snow-free surface elevation data for assessing coastal erosion and flooding hazards. Ground control data and aerial lidar data were collected on August 18, 2021, and subsequently processed using a suite of geospatial processing software. All files can be downloaded from the Alaska Division of Geological & Geophysical Surveys website (http://doi.org/10.14509/31033).
This metadata record supports the data entry in the NOAA Digital Coast Data Access Viewer (DAV).
The NOAA Office for Coastal Management (OCM) downloaded laz point data files from the AK DGGS (Alaska Division of Geological and Geophysical Surveys) website (https://dggs.alaska.gov/pubs/id/31033). The data were processed to the NOAA Digital Coast Data Access Viewer (DAV) to make the data available for bulk and custom downloads. In addition to these lidar point data, the bare earth Digital Elevation Models (DEM) created from the lidar point data are also available. These data are available for custom download at the link provided in the URL section of this metadata record.
Distribution Information
-
Not Applicable
Create custom data files by choosing data area, product type, map projection, file format, datum, etc. A new metadata will be produced to reflect your request using this record as a base. Change to an orthometric vertical datum is one of the many options.
-
LAS/LAZ - LASer
Bulk download of data files in LAZ format, geographic coordinates, orthometric heights. Note that the vertical datum (hence elevations) of the files here are different than described in this document. They will be in an orthometric datum.
None
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. Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations.
Controlled Theme Keywords
COASTAL ELEVATION, elevation, TERRAIN ELEVATION
Child Items
No Child Items for this record.
Contact Information
Point of Contact
NOAA Office for Coastal Management (NOAA/OCM)
coastal.info@noaa.gov
(843) 740-1202
https://coast.noaa.gov
Metadata Contact
NOAA Office for Coastal Management (NOAA/OCM)
coastal.info@noaa.gov
(843) 740-1202
https://coast.noaa.gov
Extents
-162.718058° W,
-162.612191° E,
60.374823° N,
60.320544° S
2021-08-18
Item Identification
Title: | 2021 AK DGGS Lidar: Tuntutuliak, AK |
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Short Name: | ak2021_tuntutuliak_m10072 |
Status: | Completed |
Creation Date: | 2021-08-18 |
Publication Date: | 2023 |
Abstract: |
Lidar-derived elevation data for Tuntutuliak, Southwest Alaska, collected August 18, 2021, Raw Data File 2023-17, provides aerial lidar derived classified point cloud data, a digital surface model (DSM), a digital terrain model (DTM), and an intensity model of Tuntutuliak, Southwest Alaska. Data were collected during leaf-on ground conditions. The survey provides snow-free surface elevation data for assessing coastal erosion and flooding hazards. Ground control data and aerial lidar data were collected on August 18, 2021, and subsequently processed using a suite of geospatial processing software. All files can be downloaded from the Alaska Division of Geological & Geophysical Surveys website (http://doi.org/10.14509/31033). This metadata record supports the data entry in the NOAA Digital Coast Data Access Viewer (DAV). The NOAA Office for Coastal Management (OCM) downloaded laz point data files from the AK DGGS (Alaska Division of Geological and Geophysical Surveys) website (https://dggs.alaska.gov/pubs/id/31033). The data were processed to the NOAA Digital Coast Data Access Viewer (DAV) to make the data available for bulk and custom downloads. In addition to these lidar point data, the bare earth Digital Elevation Models (DEM) created from the lidar point data are also available. These data are available for custom download at the link provided in the URL section of this metadata record. |
Purpose: |
The survey provides snow-free surface elevation data for assessing coastal erosion and flooding hazards. |
Supplemental Information: |
>boundaries: A boundary, also known as an Area of Interest (AOI) or border, that defines the area covered by the data. >classified_points: Classified point cloud data are provided in compressed LAZ format. Data are classified following ASPRS 2019 guidelines and contain return and intensity information. The average pulse spacing is 55.9 cm, and the average density is 3.21 pts/m2. >dsm: The DSM represents surface elevations, including heights of vegetation, buildings, boardwalks, powerlines, etc. The DSM is a single-band, 32-bit GeoTIFF file of 50-centimeter resolution. No Data value is set to -3.40282306074e+38 (32-bit, floating-point minimum). >dtm: The DTM represents bare earth elevations, excluding vegetation, bridges, buildings, etc. The DTM is a single-band, 32-bit float GeoTIFF file of 50-centimeter resolution. No Data value is set to -3.40282306074e+38. >lidar_intensity: The lidar intensity image depicts the relative amplitude of reflected signals contributing to the point cloud. Lidar intensity is primarily 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 1-meter resolution. No Data value is set to -3.40282306074e+38. |
Keywords
Theme Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION
|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION
|
ISO 19115 Topic Category |
elevation
|
Spatial Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > ALASKA
|
Global Change Master Directory (GCMD) Location Keywords |
VERTICAL LOCATION > LAND SURFACE
|
UNCONTROLLED | |
Alaska Division of Geological & Geophysical Surveys | Kinak River |
Alaska Division of Geological & Geophysical Surveys | Southwest Alaska |
Instrument Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Instrument Keywords |
LIDAR > Light Detection and Ranging
|
Platform Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Platform Keywords |
Airplane > Airplane
|
Physical Location
Organization: | Office for Coastal Management |
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City: | Charleston |
State/Province: | SC |
Data Set Information
Data Set Scope Code: | Data Set |
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Data Set Type: | Elevation |
Maintenance Frequency: | None Planned |
Data Presentation Form: | Model (digital) |
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. Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners |
Data Set Credit: | This survey area is on the traditional homelands of the Yup'ik people. Data collection and processing were funded by the National Fish and Wildlife Foundation (now known as the National Coastal Resilience Fund), grant number 0318.20.069342, through the Alaska Native Tribal Health Consortium. 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., Zechmann, J.M. Herbst, A.M. Buzard, R.M. |
Support Roles
Data Steward
Date Effective From: | 2024 |
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Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Distributor
Date Effective From: | 2024 |
---|---|
Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Metadata Contact
Date Effective From: | 2024 |
---|---|
Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Point of Contact
Date Effective From: | 2024 |
---|---|
Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Extents
Currentness Reference: | Ground Condition |
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Extent Group 1
Extent Group 1 / Geographic Area 1
W° Bound: | -162.718058 | |
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E° Bound: | -162.612191 | |
N° Bound: | 60.374823 | |
S° Bound: | 60.320544 |
Extent Group 1 / Time Frame 1
Time Frame Type: | Discrete |
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Start: | 2021-08-18 |
Spatial Information
Spatial Resolution
Horizontal Distance: | 0.56 Meter |
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Spatial Representation
Representations Used
Grid: | No |
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Vector: | Yes |
Text / Table: | No |
TIN: | No |
Stereo Model: | No |
Video: | No |
Vector Representation 1
Point Object Present?: | Yes |
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Point Object Count: | 8012212 |
Reference Systems
Reference System 1
Coordinate Reference System |
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Access Information
Security Class: | Unclassified |
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Data Access Procedure: |
Data is available online for bulk and custom downloads |
Data Access Constraints: |
None |
Data 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. Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations. |
Distribution Information
Distribution 1
Start Date: | 2024-02-09 |
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End Date: | Present |
Download URL: | https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=10072/details/10072 |
Distributor: | NOAA Office for Coastal Management (NOAA/OCM) (2024 - Present) |
File Name: | Customized Download |
Description: |
Create custom data files by choosing data area, product type, map projection, file format, datum, etc. A new metadata will be produced to reflect your request using this record as a base. Change to an orthometric vertical datum is one of the many options. |
Distribution Format: | Not Applicable |
Compression: | Zip |
Distribution 2
Start Date: | 2024-02-09 |
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End Date: | Present |
Download URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/10072/index.html |
Distributor: | NOAA Office for Coastal Management (NOAA/OCM) (2024 - Present) |
File Name: | Bulk Download |
Description: |
Bulk download of data files in LAZ format, geographic coordinates, orthometric heights. Note that the vertical datum (hence elevations) of the files here are different than described in this document. They will be in an orthometric datum. |
Distribution Format: | LAS/LAZ - LASer |
Compression: | LAZ |
URLs
URL 1
URL: | https://coast.noaa.gov/dataviewer/ |
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Name: | NOAA's Office for Coastal Management (OCM) Data Access Viewer (DAV) |
URL Type: |
Online Resource
|
File Resource Format: | HTML |
Description: |
The Data Access Viewer (DAV) allows a user to search for and download elevation, imagery, and land cover data for the coastal U.S. and its territories. The data, hosted by the NOAA Office for Coastal Management, can be customized and requested for free download through a checkout interface. An email provides a link to the customized data, while the original data set is available through a link within the viewer. |
URL 2
URL: | https://dggs.alaska.gov/webpubs/dggs/rdf/text/rdf2023_017.pdf |
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Name: | Lidar Report |
URL Type: |
Online Resource
|
File Resource Format: | |
Description: |
Link to the lidar report. |
URL 3
URL: | https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/10072/supplemental/ak2021_tuntutuliak_m10072.kmz |
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Name: | Browse Graphic |
URL Type: |
Browse Graphic
|
File Resource Format: | kmz |
Description: |
This graphic displays the footprint for this lidar data set. |
URL 4
URL: | https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=10073/details/10073 |
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Name: | Custom DEM Download |
URL Type: |
Online Resource
|
File Resource Format: | Zip |
Description: |
Link to custom download, from the Data Access Viewer (DAV), the raster Digital Elevation Model (DEM) data that were created from this lidar data set. |
Issues
Issue 1
Issue Date: | 2024-02-22 |
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Issue: |
There are points that are classified as ground that fall in ponds/lakes and streams/rivers. |
Data Quality
Horizontal Positional Accuracy: |
We did not measure horizontal accuracy for this collection. |
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Vertical Positional Accuracy: |
We measured a mean offset of 48.8 cm between 33 control points and the point cloud. We reduced this offset to 0.1 cm by performing a vertical transformation of the lidar point data. We used ten checkpoints to determine the non-vegetated vertical accuracy (NVA) of the point cloud ground class using a Triangulated Irregular Network (TIN) approach. We calculated the project NVA to have a root mean square error (RMSE) of 3.7 cm. We evaluated the relative accuracy for this dataset as the interswath overlap consistency and measured it at 6.7 cm RMSE. |
Completeness Report: |
This data release is complete. |
Conceptual Consistency: |
This is a full-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. |
Data Management
Have Resources for Management of these Data Been Identified?: | Yes |
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Approximate Percentage of Budget for these Data Devoted to Data Management: | Unknown |
Do these Data Comply with the Data Access Directive?: | Yes |
Actual or Planned Long-Term Data Archive Location: | NCEI-NC |
How Will the Data Be Protected from Accidental or Malicious Modification or Deletion Prior to Receipt by the Archive?: |
Data is backed up to cloud storage. |
Lineage
Lineage Statement: |
Data were collected by the Alaska Division of Geological and Geophysical Surveys (AK DGGS). The data were downloaded by the NOAA Office for Coastal Management (OCM) and processed to make it available for custom download from the NOAA Digital Coast Data Access Viewer (DAV) and for bulk download from AWS S3. |
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Sources
AK Department of Geology and Geophysical Surveys (AK DGGS) Lidar
Contact Role Type: | Originator |
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Contact Type: | Organization |
Contact Name: | AK DGGS |
Citation URL: | https://dggs.alaska.gov/webpubs/data/rdf2023_017_lidar-tuntutuliak-classified_points.zip |
Citation URL Name: | 2021 Tuntutuliak, AK Lidar Download |
Process Steps
Process Step 1
Description: |
Ground survey - We deployed a Trimble R10 GNSS receiver at Tuntutuliak Airport. It provided a base station occupation and real-time kinematic (RTK) corrections to points we surveyed with a rover Trimble R8 GNSS receiver (internal antenna). We collected 43 ground control and checkpoints to use for calibration and to assess the vertical accuracy of the point cloud. Points were collected on bare earth, boardwalks, and vegetation (tall grass or alder). We processed and delivered all data in NAD83 (2011) UTM3N and vertical datum NAVD88 GEOID12B. |
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Process Date/Time: | 2021-08-18 00:00:00 |
Process Step 2
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 refresh rate of 400,000 pulses per second at a scan rate of 200 lines per second. We used a Cessna 180 fixed-wing platform to survey from an elevation of ~200 m above ground level, at a ground speed of ~40 m/s, and with a scan angle set from 80 to 280 degrees. The total survey area covers ~19 km2. We flew the aerial survey on August 18, 2021, taking off from Bethel Airport and landing at Tuntutuliak Airport. Data was collected from 12:10 pm to 1:10 pm AKST. The weather throughout the survey was clear, with no wind. |
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Process Date/Time: | 2021-08-18 00:00:00 |
Process Step 3
Description: |
Lidar dataset processing - We processed point data 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. We processed IMU and GNSS data in Inertial Explorer, and we used Spatial Explorer software 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. We created macros in Terrasolid software and classified points in accordance with 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. We used ArcGIS Pro to derive raster products from the point cloud. The DSM was interpolated from maximum return values from the ground, vegetation, bridge deck, and building classes using a binning method. The DTM was interpolated from all ground class returns, also using a binning method and minimum values. In ArcGIS Pro, we produced an intensity image by binning and averaging ground, vegetation, building, and bridge deck classes. |
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Process Date/Time: | 2022-01-01 00:00:00 |
Process Step 4
Description: |
The NOAA Office for Coastal Management (OCM) downloaded 34 laz point data files from the Alaska Division of Geological and Geophysical Surveys (AK DGGS). The data were in UTM Zone 3 (NAD83 2011), meters coordinates and NAVD88 (Geoid12b) elevations in meters. According to the lidar report, the data were classified as: 1 - Unclassified, 2 - Ground, 3 - Low Vegetation (0.05 m - 0.2 m), 4 - Medium Vegetation (0.2 m - 3 m), 5 - High Vegetation (3 m - 40 m), 6 - Building, 7 - Low Noise, 10 - Bridge Decks, 18 - High Noise. There were also points that were classified as 20 and 31 that were not listed in either the lidar report or in the provided metadata. These points were assumed to be Noise classes by OCM. AK DGGS confirmed that the class 20 and 31 points should be re-classified as 18 - High Noise. The Class 10 points were re-classified to Class 17 - Bridge Deck in order to be in line with the USGS spec. During review of the data, OCM also noted that there are points that fall in ponds/lakes and streams/rivers that are classified as ground. OCM processed all classifications of points to the Digital Coast Data Access Viewer (DAV), the classes available for download from the DAV are: 1, 2, 3, 4, 5, 6, 7, 17,18. OCM performed the following processing on the data for Digital Coast storage and provisioning purposes: 1. Internal OCM scripts were run to check the number of points by classification and by flight ID and the gps, elevation, and intensity ranges. 2. Internal OCM scripts were run on the laz files to: a. Re-classify the Class 20 and 31 points to 18 - High Noise and the Class 10 points to 17 - Bridge Deck b. Convert from orthometric (NAVD88) elevations to NAD83 (2011) ellipsoid elevations using the Geoid12b model c. Convert the laz files from UTM Zone 3 (NAD83 2011), meters coordinates to geographic coordinates d. Assign the geokeys, sort the data by gps time and zip the data to database and to AWS S3. |
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Process Date/Time: | 2024-03-06 00:00:00 |
Process Contact: | Office for Coastal Management (OCM) |
Related Items
Item Type | Relationship Type | Title |
---|---|---|
Data Set (DS) | Cross Reference |
2021 AK DGGS Lidar DEM: Tuntutuliak, AK |
Catalog Details
Catalog Item ID: | 72102 |
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GUID: | gov.noaa.nmfs.inport:72102 |
Metadata Record Created By: | Rebecca Mataosky |
Metadata Record Created: | 2024-02-09 20:55+0000 |
Metadata Record Last Modified By: | Rebecca Mataosky |
Metadata Record Last Modified: | 2024-03-06 21:13+0000 |
Metadata Record Published: | 2024-02-13 |
Owner Org: | OCMP |
Metadata Publication Status: | Published Externally |
Do Not Publish?: | N |
Metadata Last Review Date: | 2024-02-13 |
Metadata Review Frequency: | 1 Year |
Metadata Next Review Date: | 2025-02-13 |