Slide Menu
Search Help Show/Hide Menu
Short Citation:
OCM Partners, 2023: 2007 Aero-Metric Inc. Topographic LiDAR: Valdez, Alaska,

Item Identification

Title: 2007 Aero-Metric Inc. Topographic LiDAR: Valdez, Alaska
Short Name: ak2007_aerometric_valdez_m1466_metadata
Status: Completed
Publication Date: 2013-02

This project was completed under USGS Contract No. 07CRCN0002, Task Order No. 070020009.

This delivery contains point cloud data in LAS 1.1 format, classified in the following manner. Class 1: Unclassified, Class 2: Ground, Class 7: Low Point (Noise), Class 9: Water, Class 10: High Point (Noise),

Class 12: Overlap, and Class 17: Port

The following are the collection parameters and equipment used to create these data sets.

Aircraft: Cessna 320 (N3443Q) and Piper Navajo (N6GR)

Lidar System: Optech ALTM Gemini (03SEN145)

Approximate Collection Altitude (Above Mean Terrain): 1800 meters

Ground Speed: 145 kts

Pulse Rate Frequency: 70 kHz

Mirror Scan Frequency: 62.6 Hz

Scan Angle (+/-): 5.3 degrees

Beam Divergence: Narrow (0.25 mrad)

Accuracy statements are based on areas of moderate terrain, with points classified as ground. Diminished accuracies are to be expected in areas of extreme terrain and dense vegetation. The accuracy of each point is

expected to meet the vertical accuracy standard. Derived products may be less accurate in areas of extreme terrain and dense vegetation due to a lesser number of points defining the ground in these areas.

Classified data sets such as this one may have varying posting due to some pulses not reaching the ground.

Original contact information:

Contact Name: Jacques Cloutier

Contact Org: Aero-Metric, Inc.

Title: Senior Geodetic Surveyor

Phone: (907) 272-4495



The purpose of this data set is to provide processed lidar data over Valdez at a nominal point spacing of 0.3 meter.



Supplemental Information:

A footprint of this data set may be viewed in Google Earth at:


Theme Keywords

Thesaurus Keyword
ISO 19115 Topic Category
None Terrain

Physical Location

Organization: Office for Coastal Management
City: Charleston
State/Province: SC

Data Set Information

Data Set Scope Code: Data Set
Maintenance Frequency: As Needed
Data Presentation Form: las
Entity Attribute Overview:

Unclassified Lidar point cloud in LAS 1.1 format

Entity Attribute Detail Citation:


Distribution Liability:

Any conclusions drawn from the analysis of this information are not the responsibility

of Aero-Metric Inc, NOAA, the Office for Coastal Management or its partners.

Support Roles

Data Steward

CC ID: 670149
Date Effective From: 2013-02
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202


CC ID: 670151
Date Effective From: 2013-02
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202

Metadata Contact

CC ID: 670152
Date Effective From: 2013-02
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202

Point of Contact

CC ID: 670150
Date Effective From: 2013-02
Date Effective To:
Contact (Organization): NOAA Office for Coastal Management (NOAA/OCM)
Address: 2234 South Hobson Ave
Charleston, SC 29405-2413
Email Address:
Phone: (843) 740-1202


Currentness Reference: Ground Condition

Extent Group 1

Extent Group 1 / Geographic Area 1

CC ID: 1133583
W° Bound: -146.641106
E° Bound: -145.913257
N° Bound: 61.15846
S° Bound: 61.036345

Extent Group 1 / Time Frame 1

CC ID: 1133579
Time Frame Type: Discrete
Start: 2007-10-16

Extent Group 1 / Time Frame 2

CC ID: 1133580
Time Frame Type: Discrete
Start: 2008-10-20

Extent Group 1 / Time Frame 3

CC ID: 1133581
Time Frame Type: Discrete
Start: 2008-10-25

Extent Group 1 / Time Frame 4

CC ID: 1133582
Time Frame Type: Discrete
Start: 2008-10-31

Spatial Information

Spatial Representation

Representations Used

Vector: Yes

Access Information

Security Class: Unclassified
Data Access Procedure:

This data can be obtained on-line at the following URL:


Data Access Constraints:


Data 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. These data

depict the heights at the time of the survey and are only accurate for that time.

Distribution Information

Distribution 1

CC ID: 740371
Download URL:
File Name: Customized Download

Create custom data files by choosing data area, product type, map projection, file format, datum, etc.

Distribution 2

CC ID: 740372
Download URL:
File Name: Bulk Download

Simple download of data files.



CC ID: 740374
URL Type:
Online Resource


CC ID: 740375
URL Type:
Online Resource


CC ID: 740376
Name: Browse Graphic
URL Type:
Browse Graphic
File Resource Format: kmz

This graphic shows topographic LiDAR coverage for Valdez, Alaska.

Activity Log

Activity Log 1

CC ID: 670171
Activity Date/Time: 2016-05-23

Date that the source FGDC record was last modified.

Activity Log 2

CC ID: 670170
Activity Date/Time: 2017-11-14

Converted from FGDC Content Standards for Digital Geospatial Metadata (version FGDC-STD-001-1998) using '' script. Contact Tyler Christensen (NOS) for details.

Activity Log 3

CC ID: 718159
Activity Date/Time: 2018-02-08

Partial upload of Positional Accuracy fields only.

Activity Log 4

CC ID: 740373
Activity Date/Time: 2018-03-13

Partial upload to move data access links to Distribution Info.

Technical Environment


Microsoft Windows 2000 Version 5.0 (Build 2195) Service Pack 4; lidarTools 1.0.9

Data Quality

Horizontal Positional Accuracy:

All these data products were acquired at 1800 meters above mean terrain (AMT) and have a horizontal accuracy of 0.3 meter, with a nominal point spacing of 0.6 meters as per manufacturer's specifications, not field verified.; Quantitative Value: 0.3 meters, Test that produced the value: Compiled to meet value (meters)

Vertical Positional Accuracy:

The final lidar data set was verified using 2554 GPS surveyed ground truth points. These points were collected by Aero-Metric along the roads throughout the developed areas of the project, using Real-Time Kinematic (RTK)

GPS techniques. The ground truth points were compared against the lidar using TerraScan, which computes the difference between each ground truth point and the lidar generated surface. These differences are recorded in an

output file in ASCII format. This file is imported into Microsoft Excel, where a statistical analysis is performed. The full lidar control check analysis is included in the deliverables for this project,

named Valdez_Low_Altitude_QC_Results.pdf. We recommend additional ground truth surveys of the data set to verify the vertical accuracy has not changed due to natural causes, such as techtonic motion or freeze/thaw cycles,

and non-natural causes such as road construction. Without ground truth survey checks this data is not recommended for design grade mapping or engineering.

; Quantitative Value: 0.092 meters, Test that produced the value: Consolidated vertical accuracy at the 95th percentile on road surfaces in meters

Completeness Measure:

Cloud Cover: 0

Completeness Report:


Conceptual Consistency:

Data has been verified using surveyed check points along road surfaces thoughout the project area.


Process Steps

Process Step 1

CC ID: 1133567

System Calibration:

Aero-Metric collected data over a previously surveyed area in Palmer, Alaska. Data was collected at the same settings as this project, using two intersecting perpendicular lines. Two GPS ground stations were operating on site

in order to minimize GPS error. The data was classified in each line separately for ground and other common features between lines, such as building roofs. This data was processed in TerraMatch 8.001 (TerraSolid, Ltd.), to

compute corrections for roll, pitch, heading, and mirror scale. These corrections were applied to the initial processing settings (.res file). The data was reprocessed to verify the corrections were applied properly. The

corrected data was then compared to ground surveyed measurements in order to check for any consistent vertical bias. The final step in calibration verified there was minimal vertical noise due to changes in intensity. This was

done by comparing elevations of points on the airport runway, one point on a runway stripe and another adjacent point on the pavement.

Process Date/Time: 2008-10-18 00:00:00

Process Step 2

CC ID: 1133570

Create a smoothed-best estimated trajectory (SBET) of the sensor at a rate of 200 Hz, by integrating the airborne GPS and IMU data. The basis of the GPS coordinates were computed using NGS OPUS, and were referenced to

NAD83 (CORS96) with GEOID06 derived orthometric heights. The maximum baseline distance for this project was 30 km, the average base line length was 12 km. The mean GPS positional accuracy for this project was +/- 0.08 meters.

Process Date/Time: 2008-11-02 00:00:00

Process Step 3

CC ID: 1133571

Integrate SBET and raw laser data to produce point cloud data in LAS 1.1 format for each flight line.

Process Date/Time: 2008-11-02 00:00:00

Process Step 4

CC ID: 1133572

Compute the roll, pitch, heading, and mirror scale correction factors for each flight line, then apply corrections to the corresponding flight line.

Process Date/Time: 2009-01-15 00:00:00

Process Step 5

CC ID: 1133573

Automated classification of the bare-earth data from the lidar point cloud using a series of algorithms customized for the types of terrain encountered in the project.

Process Date/Time: 2009-01-16 00:00:00

Process Step 6

CC ID: 1133574

Manual classification of any data which appears to be bare-earth but was not properly classified using the automated methods.

Process Date/Time: 2009-03-20 00:00:00

Process Step 7

CC ID: 1133575

The shorelines of the lakes and port areas were determined using manual techniques, starting with digitized shorelines from the orthophotography of the project area. The lidar points then underwent an intensive manual

edit to determine with greater accuracy the points which represented the water surface. For the final data products the mean elevation of the water on each lake was used to determine its fixed elevation. The port areas

fixed elevation was determined using the highest water point in the port data set. This value was found to be 4.72 meters. All points below 4.72 meters in the port area were fixed to this elevation, as per the contract.

Process Date/Time: 2009-05-25 00:00:00

Process Step 8

CC ID: 1133576

Create point clouds in LAS 1.1 format for all returns.

Process Date/Time: 2009-05-26 00:00:00

Process Step 9

CC ID: 1133577

Data verified using survey control points, located throughout the area.

Process Date/Time: 2009-05-27 00:00:00

Process Step 10

CC ID: 1133568

The metadata was updated for Bounding coordinates, Spatial Reference info using FGDC template

Process Date/Time: 2009-06-18 00:00:00

Process Step 11

CC ID: 1133569

The NOAA Office for Coastal Management (OCM) received topographic files in LAS 1.1 format. The files contained lidar

elevation and intensity measurements. The data were received in projected coordinates of NAD83 UTM6N, meters

and were vertically referenced to NAVD88 orthometric elevations using GEOID06(Alaska). The vertical units of the data were

meters. OCM performed the following processing for data storage and Digital Coast provisioning purposes:

1. LAS Classifications 11(first return only), 13(first of many returns), 14(second of many returns), 15(third of many returns), 16(last of many returns) were all placed into Class 1 (Unclassified)

2. The topographic las files were converted from Projected Coordinates (NAD83 UTM6N, meters) to Geographic Coordinates (NAD83, decimal degrees).

3. The topographic las files were vertically converted from orthometric elevations (NAVD88) to ellipsoidal elevations (NAD83) using GEOID06.

Process Date/Time: 2013-02-01 00:00:00

Catalog Details

Catalog Item ID: 49619
GUID: gov.noaa.nmfs.inport:49619
Metadata Record Created By: Anne Ball
Metadata Record Created: 2017-11-15 15:21+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2022-08-09 17:11+0000
Metadata Record Published: 2022-03-16
Owner Org: OCMP
Metadata Publication Status: Published Externally
Do Not Publish?: N
Metadata Last Review Date: 2022-03-16
Metadata Review Frequency: 1 Year
Metadata Next Review Date: 2023-03-16