gov.noaa.nmfs.inport:67831
eng
UTF8
dataset
Elevation
OCM Partners
resourceProvider
NOAA Office for Coastal Management
(843) 740-1202
2234 South Hobson Ave
Charleston
SC
29405-2413
coastal.info@noaa.gov
https://coast.noaa.gov
WWW:LINK-1.0-http--link
NOAA Office for Coastal Management Website
NOAA Office for Coastal Management Home Page
information
pointOfContact
2024-02-29T00:00:00
ISO 19115-2 Geographic Information - Metadata Part 2 Extensions for imagery and gridded data
ISO 19115-2:2009(E)
EPSG::26906
EPSG::6360
2011 FEMA Lidar DEM: Cordova, Alaska
2011
creation
2012-04-24
publication
NOAA/NMFS/EDM
67831
https://www.fisheries.noaa.gov/inport/item/67831
WWW:LINK-1.0-http--link
Full Metadata Record
View the complete metadata record on InPort for more information about this dataset.
information
https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/entwine/geoid12b/9577/ept.json
WWW:LINK-1.0-http--link
Entwine Point Tiles (EPT)
Entwine Point Tile (EPT) is a simple and flexible octree-based storage format for point cloud data. The data is organized in such a way that the data can be reasonably streamed over the internet, pulling only the points you need. EPT files can be queried to return a subset of the points that give you a representation of the area. As you zoom further in, you are requesting higher and higher densities. A dataset in EPT will contain a lot of files, however, the ept.json file describes all the rest. The EPT file can be used in Potree and QGIS to view the point cloud.
download
https://elevation.alaska.gov/
WWW:LINK-1.0-http--link
Lidar Reports
Lidar acquisition and QA reports are available from the AK DGGS Elevation Portal.
download
https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9577/details/9577
WWW:LINK-1.0-http--link
Custom Point Download
Link to custom download, from the Data Access Viewer (DAV), the lidar point data from which these raster Digital Elevation Model (DEM) data were created.
download
https://coast.noaa.gov/lidar/viewer/v/noaapotree.html?m=9577&g=geoid12b
WWW:LINK-1.0-http--link
Potree 3D View
Link to view the point cloud (using the Entwine Point Tile (EPT) format) in the 3D Potree viewer.
download
https://coast.noaa.gov/dataviewer/
WWW:LINK-1.0-http--link
NOAA's Office for Coastal Management (OCM) Data Access Viewer (DAV)
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.
download
Bare Earth LiDAR point cloud data provided for this project is compliant with FEMA Guidelines and Specifications Procedure Memorandum 61.
LiDAR derived products for two areas of interest within the Cordova, Alaska area, consisting of 32 square miles, were developed to support coastal or riverine H&H analysis and floodplain boundary delineation.
The NOAA Office for Coastal Management (OCM) downloaded this data set from this AK DGGS site:
https://elevation.alaska.gov/
These files were 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. No metadata record was provided with the data. This record is populated with information from the FEMA Starr technical and QA reports downloaded from the Alaska Dept. of Geological and Geophysical Surveys Elevation Portal.
In addition to these bare earth Digital Elevation Model (DEM) data, the lidar point data that these DEM data were created from, are also available. These data are available for custom download at the link provided in the URL section of this metadata record.
The purpose of these terrain datasets are to represent the topography of a watershed and/or floodplain environment for Cordova, Alaska coastal or riverine hydraulic and hydrologic modeling. All terrain data collected for hydrologic analysis, hydraulic analysis, floodplain boundary delineation, and/or testing of floodplain boundary standard compliance meets the requirements outlined in FEMA Appendix A: Guidance for Aerial Mapping and Survey and FEMA Procedure Memorandum 61: Standards for LiDAR and Other High Quality Digital Topography.
Federal Emergency Management Agency
completed
NOAA Office for Coastal Management
(843) 740-1202
2234 South Hobson Ave
Charleston
SC
29405-2413
coastal.info@noaa.gov
https://coast.noaa.gov
WWW:LINK-1.0-http--link
NOAA Office for Coastal Management Website
NOAA Office for Coastal Management Home Page
information
pointOfContact
NOAA Office for Coastal Management
(843) 740-1202
2234 South Hobson Ave
Charleston
SC
29405-2413
coastal.info@noaa.gov
https://coast.noaa.gov
WWW:LINK-1.0-http--link
NOAA Office for Coastal Management Website
NOAA Office for Coastal Management Home Page
information
custodian
unknown
https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/9577/supplemental/ak2011_cordova_m9577.kmz
This graphic displays the footprint for this lidar data set.
KMZ
EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION
EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION > DIGITAL ELEVATION/TERRAIN MODEL (DEM)
EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION
theme
Global Change Master Directory (GCMD) Science Keywords
17.0
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > ALASKA
VERTICAL LOCATION > LAND SURFACE
place
Global Change Master Directory (GCMD) Location Keywords
17.0
LIDAR > Light Detection and Ranging
instrument
Global Change Master Directory (GCMD) Instrument Keywords
17.2
Airplane > Airplane
platform
Global Change Master Directory (GCMD) Platform Keywords
17.2
DEMs - partner (no harvest)
project
InPort
otherRestrictions
Cite As: OCM Partners, [Date of Access]: 2011 FEMA Lidar DEM: Cordova, Alaska [Data Date Range], https://www.fisheries.noaa.gov/inport/item/67831.
NOAA provides no warranty, nor accepts any liability occurring from any incomplete, incorrect, or misleading data, or from any incorrect, incomplete, or misleading use of the data. It is the responsibility of the user to determine whether or not the data is suitable for the intended purpose.
otherRestrictions
Access Constraints: None
otherRestrictions
Use Constraints: 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.
otherRestrictions
Distribution Liability: No warranty expressed or implied is made by FEMA regarding the utility of the data on any other system nor shall the act of distribution constitute any such warranty.
Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners.
unclassified
2011 FEMA Lidar: Cordova, Alaska
NOAA/NMFS/EDM
67815
crossReference
NOAA Data Management Plan (DMP)
NOAA/NMFS/EDM
67831
https://www.fisheries.noaa.gov/inportserve/waf/noaa/nos/ocmp/dmp/pdf/67831.pdf
WWW:LINK-1.0-http--link
NOAA Data Management Plan (DMP)
NOAA Data Management Plan for this record on InPort.
information
crossReference
grid
eng; US
elevation
-145.814597
-145.604905
60.51737
60.568287
| Currentness: Ground Condition
2011-09-23
| Currentness: Ground Condition
2011-09-25
false
eng
false
Appendix M of FEMA Guidelines and Specifications for FEMA Flood Hazard Mapping Partners contains a detailed description of the data themes and references to other relevant information.
Zip
Zip
GeoTIFF
NOAA Office for Coastal Management
(843) 740-1202
2234 South Hobson Ave
Charleston
SC
29405-2413
coastal.info@noaa.gov
https://coast.noaa.gov
WWW:LINK-1.0-http--link
NOAA Office for Coastal Management Website
NOAA Office for Coastal Management Home Page
information
distributor
https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9578/details/9578
WWW:LINK-1.0-http--link
Customized Download
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.
download
https://noaa-nos-coastal-lidar-pds.s3.us-east-1.amazonaws.com/dem/AK_Cordova_DEM_2011_9578/index.html
WWW:LINK-1.0-http--link
Bulk Download
Bulk download of data files in GeoTiff format, UTM Zone 6 NAD83 (EPSG: 26906), meters coordinates and orthometric heights in feet (EPSG: 6360).
download
dataset
Vertical Positional Accuracy
Fundamental Vertical Accuracy (FVA) checkpoints are located only in open terrain, where there is a high probability that the sensor will have detected the ground surface without influence from surrounding vegetation and/or buildings. Checkpoints are located on flat or uniformly sloping terrain and at least five (5) meters away from a change in slope. Checkpoints are located randomly across the acquisition area. At least 20 FVA points were collected for each test.
Consolidated Vertical Accuracy (CVA) checkpoints are collected randomly across different land use types using the ASPRS NSSDA land cover types. The points are located in flat areas with no substantial elevation breaks within a five meter radius. The CVA assessment incorporates a representative sample of the FVA assessment points into the dataset to save on the total number of points collected. CVA points were not collected for any land class comprising less that 10% of the total project area; this may have resulted in less than 4 land classes being collected in a particular area. At least 15 CVA points were collected and 5 FVA points used, for a total of at least 20 points for the CVA testing. All points were collected at three times the accuracy of the surface being checked. Thus to check a 24.5 cm surface the points were collected accurate to 8 cm.
Tests were conducted when processing by the LiDAR vendor was complete and points were called for. The surveyor provided the point coordinates in an excel spreadsheet to the LiDAR vendor. The LiDAR vendor found the corresponding elevation from a surface created from the LiDAR points, filled in the spreadsheet and returned it to the surveyor who compared the elevation of the LiDAR data with that of the accuracy check point, calculated the difference and reported their findings both in terms of RMSEz and at the 95% confidence level (computed as RMSEz x 1.9600). LiDAR datasets passing the quality control checks were delivered to STARR for quality assurance approval.
Tested 36.0 cm consolidated vertical accuracy at 95th percentile in: open terrain, forest terrain, and urban terrain. The Root Mean Square Error for the elevation differences between GPS control points and LiDAR points is 15.8 cm calculated with 43 supplemental vertical accuracy points (SVA).
The vertical accuracy requirements based on flood risk and terrain slope are met with 10.2 cm and 36.0 cm for both FVA and CVA testing. The mandatory requirements for the highest specification for vertical accuracy, 95% confidence levels are < 24.5 cm for FVA and <36.3 cm for CVA.
Independent review of submitted FVA and CVA survey data with vendor provided LAS files. Survey data points containing field collected GPS elevation values were buffered by 10 meters. LiDAR points contained within the buffered areas are selected and used to create a TIN. The TIN facet z value closest to the x and y control point location is compared to the height of the survey point. The height difference is evaluated statistically and compared to the submitted FVA and CVA testing results to insure the vertical accuracy meets project expectations.
Consolidated Vertical Accuracy (CVA) equal to the 95th Percentile calculated against the bare earth surface in all ground cover classes was 0.36 meters.
Fundamental Vertical Accuracy (FVA) equal to the 95% confidence level (RMSE[z] x 1.9600) calculated against the point cloud (unclassified LAS) was 0.102 meters.
Completeness Report
Elevation data has been collected for all areas inside project boundaries. No gaps as defined by FEMA Procedural Memo No. 61 are known to exist within the dataset.
Conceptual Consistency
The terrain data have been confirmed as complete with content as specified by FEMA Procedural Memo No. 61.
Data were collected by Aerometric, Inc. for FEMA. 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).
Process Steps For products derived from Cordova, Alaska LiDAR Data:
1-Create Cordova, AK ESRI file geodatabase feature dataset with NAD_1983_UTM_Zone_6N projection.
2-Use ESRI 3D analyst tool LAS to multipoint and created bare earth multipoint featureclass stored within Cordova, AK file geodatabase feature dataset.
3-Use ESRI Arc Catalog to create an ESRI terrain dataset stored within Cordova, AK file geodatabase feature dataset. The multipoints were added to the terrain as mass points using the shape as the height source and the study area polygon was added to the terrain as a soft clip without any height source. 1 meter or 3.2808399 ft average point spacing used. This was determined from Cordova, AK acquisition metadata.
4-Create Bare Earth DEM file geodatabase for Cordova, AK
5-Use 3D analyst tool Terrain to raster to create 2 meter DEM and store within Cordova, AK Bare Earth DEM file geodatabase.
6-Create Raster Index Polygon
7-Using ERDAS Imagine split 2 meter AOI DEM into GeoTif Format based on raster index.
8-Using ArcCatalog converted GeoTif DEMs into Ascii raster format.
9-Create Cordova, AK Cartographic Contours and Analysis Contours file geodatabase feature datasets with NAD_1983_UTM_Zone_6N projection.
10-Use ESRI spatial analyst neighborhood tool focal statistics (mean statistic using circle with 3 cell radius) on each GeoTif bare earth DEM.
11-Use ESRI spatial analyst surface tool Contour to create 2ft contour from focal mean GeoTif DEMs and stored within Cordova, AK Cartographic Contours file geodatabase feature dataset.
12-Use ESRI spatial analyst neighborhood tool focal statistics (sum statistic using weighted kernel) on each GeoTif bare earth DEM.
Weighted Kernel: 3 3
.005 .005 .005
.005 .960 .005
.005 .005 .005
13-Use ESRI spatial analyst surface tool Contour to create 2ft contour from focal sum GeoTif DEMs and stored within Cordova, AK Analysis Contours file geodatabase feature dataset.
2012-01-01T00:00:00
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 6 NAD83, meters coordinates and NAVD88 (Geoid09) elevations in feet. The bare earth raster files were at a 1 meter grid spacing. No metadata record was provided with the data. This record is populated with information from the FEMA Starr technical and QA reports downloaded from the AK Dept. of Geological and Geophysical Surveys Elevation Portal.
OCM performed the following processing on the data for Digital Coast storage and provisioning purposes:
1. Used internal an script to assign the EPSG codes (Horizontal EPSG: 26906 and Vertical EPSG: 6360) to the GeoTiff formatted files.
2. Copied the files to https.
2022-09-02T00:00:00
Office for Coastal Management
processor
Alaska Division of Geological and Geophysical Surveys (DGGS)
AK DGGS
https://elevation.alaska.gov/
WWW:LINK-1.0-http--link
AK DGGS Elevation Portal
Source Citation URL
information
publisher