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Short Citation:
OCM Partners, 2024: September 2002 Lidar Point Data of Southern California Coastline: Dana Point to Point La Jolla,

Item Identification

Title: September 2002 Lidar Point Data of Southern California Coastline: Dana Point to Point La Jolla
Short Name: scripps_20020909_m46_metadata
Status: Completed
Publication Date: 2003-04-22

This data set contains lidar point data from a strip of Southern California coastline (including water,

beach, cliffs, and top of cliffs) from Dana Point to Point La Jolla. The geographic extent of the data set is equivalent to the

18 quarter-quadrangles listed in Other_Citation_Details plus 30 meters of overedge beyond the extents of each quarter-quadrangle

(overlap between quads). The data set was created by combining data collected using an Optech Inc. Airborne Laser Terrain Mapper

(ALTM) 1225 in combination with geodetic quality Global Positioning System (GPS) airborne and ground-based receivers. The Bureau of

Economic Geology, the University of Texas at Austin owns and operates an ALTM 1225 system (serial number 99d118). The system was

installed in a single engine Cessna 206 (tail number N4589U) owned and operated by the Texas State Aircraft Pooling Board. The

lidar data set described by this document was collected on 9 September 2002 (25202) between 22:44 and 02:02 UTC (see Lineage,

Source_Information, Source_Contribution for pass information). Conditions on that day were clear skies, no fog or low clouds,

but haze. 99d118 instrument settings for this flight were; laser pulse rate: 25kHz, scanner rate: 26Hz, scan angle: +/-20deg,

beam divergence: narrow, altitude: 760-960m AGL, and ground speed: 99-110kts. Two GPS base stations (Scripps pier and San Onofre

Power Plant, see Lineage, Source_Information, Source_Contribution for coordinates) were operating during the survey. Data

represented is all points including terrain, vegetation, and structures. This data also contains returns from the water surface.

No processing has been done to remove returns from terrain, vegetation, structures or water surfaces.

Original contact information:

Contact Name: Julie Thomas/Randy Bucciarelli

Contact Org: SCBPS/CDIP, Scripps Institution of Oceanography

Title: Project Managers

Phone: 858-534-3032


The data described in this document will be compared with previous and forthcoming data sets to determine rates of

shoreline change along the Southern California coastline. The SCBPS program is designed to improve the understanding of beach

sand transport by waves and currents, thus improving local and regional coastal management.



Other Citation Details:

quad names: Del Mar, Dana Point, Encinitas, La Jolla, Las Pulgas Canyon, Oceanside, San Clemente, San Luis Rey, San Onofre


Supplemental Information:

The ALTM 1225 has the following specifications: operating altitude = 410-2,000 m AGL; laser pulse rate = 25 kHz; laser scan

angle = variable from 0 to +/-20deg from nadir; scanning frequency = variable, 28 Hz at the 20deg scan angle; and beam

divergence = 0.2 milliradian (half angle, 1/e). The ALTM 1225 does not digitize and record the waveform of the laser reflection,

but records the range and backscatter intensity of the first and last laser reflection using a constant-fraction discriminator

and two Timing Interval Meters (TIM).

ALTM elevation points are computed using three sets of data: laser ranges and their associated scan angles, platform position

and orientation information, and calibration data and mounting parameters (Wehr and Lohr, 1999). Global Positioning System (GPS)

receivers in the aircraft and on the ground provide platform positioning. The GPS receivers record pseudo-range and phase

information for post-processing. Platform orientation information comes from an Inertial Measurement Unit (IMU) containing three

orthogonal accelerometers and gyroscopes. An aided-Inertial Navigation System (INS) solution for the aircraft's attitude is

estimated from the IMU output and the GPS information. Wehr, A. and U. Lohr, 1999, Airborne laser scanning - an introduction

and overview, ISPRS Journal of Photogrammetry and Remote Sensing, vol. 54, no.2-3, pp.68-82.


Theme Keywords

Thesaurus Keyword
ISO 19115 Topic Category
None beach
None intensity
None Latitude
None Longitude
None point file
None shoreline

Temporal Keywords

Thesaurus Keyword
None 2002
None September

Physical Location

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

Data Set Information

Data Set Scope Code: Data Set
Maintenance Note:

None planned, as needed

Distribution Liability:

This data was collected in partnership with Scripps Institution of Oceanography,

The University of California, San Diego. Any conclusions drawn from analysis of this information are not the responsibility

of the Bureau of Economic Geology or the University of Texas at Austin, NOAA, the OCM or its partners.

Data Set Credit: SCBPS/CDIP is jointly funded by the US Army Corps of Engineers and the California Department of Boating and Waterways. The initial data are collected by Bureau of Economic Geology, The University of Texas at Austin: R. Gutierrez and T. Hepner. Center for Space Research, The University of Texas at Austin: A. Neuenschwander. Data are further classified and processed by the SCBPS group, located at the Scripps Institution of Oceanography.

Support Roles

Data Steward

CC ID: 686420
Date Effective From: 2003-04-22
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: 686422
Date Effective From: 2003-04-22
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: 686423
Date Effective From: 2003-04-22
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: 686421
Date Effective From: 2003-04-22
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: 1136025
W° Bound: -117.743455
E° Bound: -117.249755
N° Bound: 33.490578
S° Bound: 32.843078

Extent Group 1 / Time Frame 1

CC ID: 1136024
Time Frame Type: Discrete
Start: 2002-09-09

Spatial Information

Spatial Representation

Representations Used

Vector: Yes

Vector Representation 1

CC ID: 686414
Point Object Present?: Yes
Point Object Count: 85441633

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.

Distribution Information

Distribution 1

CC ID: 742547
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: 742548
Download URL:
File Name: Bulk Download

Simple download of data files.



CC ID: 742550
URL Type:
Online Resource


CC ID: 742551
URL Type:
Online Resource

Activity Log

Activity Log 1

CC ID: 686444
Activity Date/Time: 2016-05-23

Date that the source FGDC record was last modified.

Activity Log 2

CC ID: 686443
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: 718603
Activity Date/Time: 2018-02-08

Partial upload of Positional Accuracy fields only.

Activity Log 4

CC ID: 742549
Activity Date/Time: 2018-03-13

Partial upload to move data access links to Distribution Info.

Data Quality

Horizontal Positional Accuracy:

Selected portions from each lidar data set (last return only) were used to generate a

1m x 1m digital elevation model (DEM). Data estimated to have a horizontal accuracy of 0.01-0.03m from ground surveys using

kinematic GPS techniques were superimposed on the lidar DEM and examined for any mismatch between the horizontal position of

the ground GPS and the corresponding feature on the lidar DEM. Horizontal agreement between the ground kinematic GPS and the

lidar was within the resolution of the 1m x 1m DEM.

Vertical Positional Accuracy:

Ground GPS surveys were conducted within the lidar survey area to acquire ground "truth"

information. The ground survey points are estimated to have a vertical accuracy of 0.01-to-0.03m. The parking lot at Torrey

Pines State Park and the Scripps Pier were surveyed using kinematic GPS techniques. A lidar data set was sorted to find data

points that fell within 0.5m of a ground GPS survey point. The mean elevation difference between the lidar and the ground GPS

was used to estimate and remove an elevation bias from the lidar. The standard deviation of these elevation differences provides

estimates of the lidar precision. The September 2002 lidar data set was determined to have an elevation bias of -0.007m when

compared to ground truth. The -0.007m bias was removed so that mean lidar elevations conform to NAVD88 with an RMSE of 0.125m.

Completeness Report:

Data were edited by an automated method to remove obvious outliers above a threshold of 150m.

Conceptual Consistency:

Not Applicable



Air and Ground GPS files from 25202

CC ID: 1136018
Publish Date: 2002-09-09
Extent Type: Discrete
Extent Start Date/Time: 2002-09-09
Source Contribution:

air and ground GPS files

base station coordinates (Easting, Northing, HAE) in NAD83:

Scripps Pier (PIER) = 476093.032, 3636524.941, -25.424

San Onofre (GPS1) = 447430.150, 3693036.731, -5.166

| Type of Source Media: digital file

Raw lidar data output from ALTM 1225

CC ID: 1136019
Publish Date: 2002-09-09
Extent Type: Discrete
Extent Start Date/Time: 2002-09-09
Source Contribution:

raw lidar data from ALTM 1225

Offshore Pass = 22:54-23:19 UTC

Pass 1 (Dana Point to Point La Jolla) = 23:22-23:52 UTC

Pass 2 (Point La Jolla to Dana Point) = 23:59-00:28 UTC

Pass 3 (Dana Point to Point La Jolla) = 00:37-01:06 UTC

Pass 4 (Point La Jolla to Dana Point) = 01:24-01:48 UTC

Pass 5 (Dana Point Area) = 01:52-01:54 UTC

Pass 6 (Dana Point Area) = 01:56-02:02 UTC

4 calibration passes between 01:10-01:23 UTC

| Type of Source Media: digital file

Process Steps

Process Step 1

CC ID: 1136020

Transfer raw ALTM 1225 flight data, airborne GPS data collected at 1 Hz using Ashtech receiver, and ground-based GPS data

collected at 1 Hz using Ashtech and Trimble 4000SSI receivers to NT workstation. Generate decimated lidar point file from above

three data sets using Optech's Realm 2.27 software. This is a 9-column ASCII data set with the following format: time tag; first

pulse Easting, Northing, HAE; last pulse Easting, Northing, HAE; first pulse intensity; and last pulse intensity. View decimated

lidar point file to check data coverage (i.e. sufficient overlap of flight lines and point spacing).

Compute base station coordinates using National Geodetic Survey's PAGES software. Computed aircraft trajectories for both base

stations using National Geodetic Survey's KINPOS software. Coordinates for base stations and trajectories are in the

International Terrestrial Reference Frame of 2000 (ITRF2000) datum. Trajectories from both base stations were merged into one.

Weighting for trajectory merge is based upon baseline length (distance from base station) and solution RMS. Transformed

trajectory solution from ITRF2000 to North American Datum of 1983 (NAD83).

Use NAD83 trajectories and aircraft inertial measurement unit data in Applanix's POSProc version 2.1.4 to compute an optimal

50Hz inertial navigation solution. Substitute the aircraft position and attitude information from the inertial navigation

solution into Realm 2.27. Extract calibration area data set from lidar point file for quality control and instrument

calibration checks. If necessary, use multiple iterations to adjust calibration parameters (pitch, roll, and scale) and

reprocess sample data set. Then generate entire lidar point file (9-column ASCII file).

Use the Geiod99 geoid model to convert from Height Above the GRS80 ellipsoid to elevations with respect to the North American

Vertical Datum 88 (NAVD88). Transfer point file from NT workstation to UNIX workstation. Parse the 9-column lidar point file

into 3.75-minute quarter-quadrangle components and apply elevation bias correction (determined during calibration step).

There are some points in the file that only contain 5-columns. These are points that either the first or last pulse was not

recorded. UTM Easting and Northing were converted to geodetic latitude and longitude with respect to the GRS80 ellipsoid.

The conversion was computed using the TMGEOD and TCONPC fortran subroutines written by T. Vincenty (NGS). Each record contains

9 columns of data: time tag (seconds in the GPS week), first return Latitude, first return Longitude, first return NAVD88,

last return Latitude, last return Longitude, last return NAVD88, first return intensity, and last return intensity.

In some cases either the first or last return values may be missing (5 columns). Latitude and longitude

are in decimal degrees with nine significant digits to retain the 0.01m resolution of the UTM coordinates. West longitude is

negative and north latitude is positive. The eighteen UTM quarter-quad files were re-organized into eleven files. UTM quarter-quads

files that were delineated by the same upper and lower latitude bounds were concatenated. The lat-long files were named by the

month-year of the survey (e.g. may02) and the lower latitude bounding the quarter-quad. Processing occurred 20020909-20030421.

Process Date/Time: 2002-09-09 00:00:00

Process Step 2

CC ID: 1136021

Created initial metadata

Process Date/Time: 2003-04-18 00:00:00

Process Step 3

CC ID: 1136022

The NOAA Office for Coastal Management (OCM) received files in ASCII format. The files contained LiDAR intensity

and elevation measurements. OCM performed the following

processing on the data to make it available within the LiDAR Data Retrieval Tool (LDART)

1. Data returned to ellipsoid heights from NAVD88, using GEOID99.

2. Data converted to LAS format.

3. The LAS data were sorted by latitude and the headers were updated.

Process Date/Time: 2007-07-24 00:00:00

Catalog Details

Catalog Item ID: 50002
GUID: gov.noaa.nmfs.inport:50002
Metadata Record Created By: Anne Ball
Metadata Record Created: 2017-11-15 15:23+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