67999
2019 AK DGGS Lidar DEM: Mt. Juneau, AK
ak2019_mt_juneau_dem_m9608_metadata
Data Set
Published / External
49404
DEMs - partner (no harvest)
Project
Completed
2019
2022
The Alaska Division of Geological & Geophysical Surveys (DGGS) used aerial lidar to produce a classified point cloud, digital surface model (DSM), digital terrain model (DTM), and intensity model of Mount Juneau, Southeast Alaska, during near snow-free ground conditions on September 6, 2019. The survey provides snow-free surface elevations for deriving snow depth distribution models with repeat surveys during snow-covered conditions. Ground control data were collected on September 5, 2019, and aerial lidar were collected on September 6, 2019, and subsequently processed in a suite of geospatial processing software. These products are released as a Raw Data File with an open end-user license. All files can be downloaded from the Alaska Division of Geological & Geophysical Surveys website (http://doi.org/10.14509/30731).
The NOAA Office for Coastal Management (OCM) downloaded this data set from this AK DGGS site:
https://elevation.alaska.gov/
This file was processed to make the data available for custom and bulk download from the NOAA Digital Coast Data Access Viewer (DAV) . The total number of files downloaded and processed was 1.
The survey provides snow-free surface elevations for deriving snow depth distribution models with repeat surveys during snow-covered conditions. The goal of this project and related works is to improve understanding of the complex interaction between the changing cryosphere, snow avalanches, natural resources, and people in their natural and built environments.
>classified point cloud data: Classified point cloud data are provided in compressed LAZ format. Data are classified in accordance with ASPRS 2014 guidelines and contain return and intensity information. The average pulse spacing is 7.5 cm and the average density is 15.58 pts/m2.
>digital surface model: The DSM represents surface elevations including heights of vegetation, buildings, 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).
>digital terrain model: 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 image: 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 1-meter resolution. No Data value is set to -3.40282306074e+38.
Theme
Global Change Master Directory (GCMD) Science Keywords
EARTH SCIENCE
Theme
Global Change Master Directory (GCMD) Science Keywords
EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION
Theme
Global Change Master Directory (GCMD) Science Keywords
EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION > DIGITAL ELEVATION/TERRAIN MODEL (DEM)
Theme
Global Change Master Directory (GCMD) Science Keywords
EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION
Theme
ISO 19115 Topic Category
elevation
Theme
ISO 19115 Topic Category
geoscientificInformation
Spatial
Global Change Master Directory (GCMD) Location Keywords
CONTINENT
Spatial
Global Change Master Directory (GCMD) Location Keywords
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA
Spatial
Global Change Master Directory (GCMD) Location Keywords
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > ALASKA
Spatial
Global Change Master Directory (GCMD) Location Keywords
VERTICAL LOCATION > LAND SURFACE
Instrument
Global Change Master Directory (GCMD) Instrument Keywords
LIDAR > Light Detection and Ranging
Platform
Global Change Master Directory (GCMD) Platform Keywords
Airplane > Airplane
Spatial
Alaska Division of Geological & Geophysical Surveys
Court House Hill
Spatial
Alaska Division of Geological & Geophysical Surveys
Ebner Falls
Spatial
Alaska Division of Geological & Geophysical Surveys
Gastineau Channel
Spatial
Alaska Division of Geological & Geophysical Surveys
Gold Creek
Spatial
Alaska Division of Geological & Geophysical Surveys
Granite Creek
Spatial
Alaska Division of Geological & Geophysical Surveys
Harris Harbor
Spatial
Alaska Division of Geological & Geophysical Surveys
Juneau
Spatial
Alaska Division of Geological & Geophysical Surveys
Mount Juneau
Spatial
Alaska Division of Geological & Geophysical Surveys
Mount Maria
Spatial
Alaska Division of Geological & Geophysical Surveys
Starr Hill
Office for Coastal Management
Charleston
SC
Data Set
Elevation
None Planned
Model (digital)
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.
These data products were funded by U.S. Geological Survey, Alaska Electric Light & Power Company, and the State of Alaska and collected and processed DGGS. We thank Coastal Helicopters 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., Wikstrom Jones, Katreen Wolken, G.J. Herbst, A.M.
Data Steward
2022
Organization
NOAA Office for Coastal Management
NOAA/OCM
coastal.info@noaa.gov
2234 South Hobson Ave
Charleston
SC
29405-2413
(843) 740-1202
https://coast.noaa.gov
NOAA Office for Coastal Management Home Page
Online Resource
Distributor
2022
Organization
NOAA Office for Coastal Management
NOAA/OCM
coastal.info@noaa.gov
2234 South Hobson Ave
Charleston
SC
29405-2413
(843) 740-1202
https://coast.noaa.gov
NOAA Office for Coastal Management Home Page
Online Resource
Metadata Contact
2022
Organization
NOAA Office for Coastal Management
NOAA/OCM
coastal.info@noaa.gov
2234 South Hobson Ave
Charleston
SC
29405-2413
(843) 740-1202
https://coast.noaa.gov
NOAA Office for Coastal Management Home Page
Online Resource
Point of Contact
2022
Organization
NOAA Office for Coastal Management
NOAA/OCM
coastal.info@noaa.gov
2234 South Hobson Ave
Charleston
SC
29405-2413
(843) 740-1202
https://coast.noaa.gov
NOAA Office for Coastal Management Home Page
Online Resource
Ground Condition
-134.478291
-134.327115
58.330648
58.299581
Discrete
2019-09-06
Yes
Vertical
EPSG:5703
NAVD88 height
North American Vertical Datum 1988
1
Gravity-related height
H
metre
up
Projected
EPSG:6337
NAD83(2011) / UTM zone 8N
NAD83 (National Spatial Reference System 2011)
GRS 1980
6378137
298.257222101
NAD83(2011)
UTM zone 8N
Transverse Mercator
1
easting
E
metre
east
Unclassified
Data is available online for bulk and custom downloads.
None
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.
2022-10-07
https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9608/details/9608
2022
Organization
NOAA Office for Coastal Management
Customized Download
Create custom data files by choosing data area, map projection, file format, etc. A new metadata will be produced to reflect your request using this record as a base.
Zip
Zip
2022-10-07
https://noaa-nos-coastal-lidar-pds.s3.us-east-1.amazonaws.com/dem/AK_Mt_Juneau_DEM_2019_9608/index.html
2022
Organization
NOAA Office for Coastal Management
Bulk Download
Bulk download of data files in the original coordinate system.
GeoTIFF
GeoTIFF
https://coast.noaa.gov/
NOAA's Office for Coastal Management (OCM) website
Online Resource
HTML
Information on the NOAA Office for Coastal Management (OCM)
https://coast.noaa.gov/dataviewer/
NOAA's Office for Coastal Management (OCM) Data Access Viewer (DAV)
Online Resource
HTML
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.
https://dggs.alaska.gov/webpubs/dggs/rdf/text/rdf2021_012.pdf
Lidar Report
Online Resource
pdf
This lidar report provides accompanying information about the collection and processing of this lidar data set.
We did not measure horizontal accuracy for this collection.
We measured a mean offset of -19.5 cm between 22 control points and the point cloud. We reduced this offset to +4.4 cm by performing a vertical transformation of the lidar point data. We used six check points 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 10.8 cm. We evaluated the relative accuracy for this dataset as the interswath overlap consistency and measured it at 8.4 cm RMSE. See the accompanying report for tables of checkpoint comparisons.
This data release is complete.
There is lower ground point density in some heavily forested areas than in areas with thinner forest canopy; however, the interpolated areas were deemed sufficient given the resolution of the products and intended scope of the work.
Data were collected by the Alaska Division of Geological and Geophysical Surveys (AK DGGS). OCM downloaded the data from the Alaska DGGS Elevation Portal and processed the data to be available for custom and bulk download from the NOAA Digital Coast Data Access Viewer (DAV).
Alaska Division of Geological and Geophysical Surveys (AK DGGS)
Organization
AK DGGS
Originator
https://elevation.alaska.gov/
AK DGGS Elevation Portal
1
Aerial photogrammetric 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 50,000 pulses per second in the alpine areas and 400,000 pulses per second over forested areas at a scan rate between 80 and 220 lines per second. We used a Bell 206 JetRanger to survey from an elevation of ~130 m above ground level, at a ground speed of ~30 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 6, 2019, with departure at 12:20 pm from Juneau International Airport, Alaska, and landed back at Juneau International Airport at 4:30 pm. The second part of the survey, covering Mount Juneau, started at 2:30 pm from Mount Anderson on Douglas Island. The weather throughout the survey was clear with no wind.
2019-09-06T00:00:00
2
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, are the result of ambiguous interpretations of received pulse time intervals and occur more frequently with higher pulse refresh rates. We processed Inertial Measurement Unit (IMU) and Global Navigation Satellite System (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) 2014 guidelines. We gave careful attention to the interpolation of the project's ground surface to compensate for inconsistent penetration through low vegetation as a function of the scan angle. Once classified, we applied a geometric transformation and converted the points from ellipsoidal heights to GEOID12B (Alaska) orthometric heights. We used ArcMap to derive raster products from the point cloud. The DSM was interpolated from maximum return values from the ground, vegetation 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 ArcMap, we produced an intensity image using closest-to-mean binning.
2019-01-01T00:00:00
3
The NOAA Office for Coastal Management (OCM) downloaded 1 raster DEM file in GeoTiff format from the Alaska DGGS Elevation Portal. The data were in UTM Zone 8N NAD83 (2011), meters coordinates and NAVD88 (Geoid12B) elevations in meters. The bare earth raster file was at a 0.5 meter grid spacing.
OCM performed the following processing on the data for Digital Coast storage and provisioning purposes:
1. Used an internal script to assign the EPSG codes (Horizontal EPSG: 6337 and Vertical EPSG: 5703) to the GeoTiff formatted file.
2. Copied the files to https.
2022-10-11T00:00:00
Organization
Office for Coastal Management
OCM
2234 South Hobson Avenue
Charleston
SC
29405-2413
https://www.coast.noaa.gov/
gov.noaa.nmfs.inport:67999
Rebecca Mataosky
2022-10-07T15:49:19
Kirk Waters
2024-01-10T19:27:33
2024-01-10
OCM Partners
OCMP
1002
Public
No
2022-10-07
1 Year
2023-10-07