Short Citation:
Office for Coastal Management, 2021: 2004 Connecticut Coastline Lidar Mapping, https://www.fisheries.noaa.gov/inport/item/48168.

Item Identification

Title: 2004 Connecticut Coastline Lidar Mapping
Short Name: ct2004_m20_metadata
Status: Completed
Publication Date: 2006-08-14
Abstract:

LIDAR data is remotely sensed high-resolution elevation data collected by an airborne collection platform. Using a

combination of laser rangefinding, GPS positioning and inertial measurement technologies; LIDAR instruments are able to make

highly detailed Digital Elevation Models (DEMs) of the earth's terrain, man-made structures and vegetation. This data was

collected at submeter resolution to provide nominal 1m spacing of collected points. Two returns were recorded for each pulse

in addition to an intensity value.

Original contact information:

Contact Org: NOAA Office for Coastal Management

Phone: 843-740-1202

Email: coastal.info@noaa.gov

Purpose:

LIDAR data is used for 3D visualization, elevation based analysis and for feature extraction.

Notes:

10191

Supplemental Information:

Reflective surface data represents the DEM created by laser energy reflected from the first surface

encountered by the laser pulse. Some energy may continue beyond this initial surface to be reflected by a subsequent surface as

represented by the Last Return data. Intensity information is captured from the Reflective Surface pulse and indicates the

relative energy returned to the sensor as compared to the energy transmitted. The Intensity image is not calibrated or normalized

but indicates differences in energy absorption due to the interaction of the surface materials with laser energy at the wavelength

transmitted by the sensor. Points are classified as on ground surface or not on ground surface to support creation of a bare earth

model from the data. Open water is classified as not bare ground.

The 2004 Connecticut Lidar Data Validation Report may be viewed at https://coast.noaa.gov/htdata/lidar1_z/geoid12a/data/20/supplemental

Keywords

Theme Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Science Keywords Earth Science > Land Surface > Topography > Terrain Elevation > Topographical Relief Maps
Global Change Master Directory (GCMD) Science Keywords Earth Science > Oceans > Bathymetry/Seafloor Topography > Seafloor Topography
Global Change Master Directory (GCMD) Science Keywords Earth Science > Oceans > Coastal Processes > Coastal Elevation
ISO 19115 Topic Category elevation
None Bathymetry/Topography
None Beach
None DEM
None Digital elevation model
None Elevation
None Erosion
None Laser
None Lidar

Spatial Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Location Keywords Continent > North America > United States Of America > Connecticut
None Connecticut
None Connecticut Coastline
None Connecticut River
None Long Island Sound
None New Haven
None New Haven Harbor
None Old Saybrook
None Quinnipiac River
None US

Physical Location

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

Data Set Information

Data Set Scope Code: Data Set
Maintenance Frequency: None Planned
Distribution Liability:

Any conclusions drawn for the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners.

Data Set Credit: This data set was developed for the NOAA OCM by Woolpert.

Support Roles

Data Steward

CC ID: 623313
Date Effective From: 2006-08-14
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

CC ID: 623315
Date Effective From: 2006-08-14
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

CC ID: 623316
Date Effective From: 2006-08-14
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

CC ID: 623314
Date Effective From: 2006-08-14
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

Extent Group 1

Extent Group 1 / Geographic Area 1

CC ID: 623319
W° Bound: -72.908092
E° Bound: -72.279933
N° Bound: 41.45389
S° Bound: 41.240042

Extent Group 1 / Time Frame 1

CC ID: 623318
Time Frame Type: Discrete
Start: 2004-10-08

Spatial Information

Spatial Representation

Representations Used

Vector: Yes

Access Information

Security Class: Unclassified
Security Classification System:

US DOD

Security Handling Description:

Information Unclassified with release control provided by NOAA/Office for Coastal Management

Data Access Procedure:

This data can be obtained on-line at the following URL: https://coast.noaa.gov/dataviewer.;

Data Access Constraints:

None

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: 743742
Download URL: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=20
Distributor:
File Name: Customized Download
Description:

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

Distribution 2

CC ID: 743743
Download URL: https://coast.noaa.gov/htdata/lidar1_z/geoid12a/data/20
Distributor:
File Name: Bulk Download
Description:

Simple download of data files.

URLs

URL 1

CC ID: 743745
URL: https://coast.noaa.gov/dataviewer
URL Type:
Online Resource

URL 2

CC ID: 743746
URL: https://coast.noaa.gov
URL Type:
Online Resource

Activity Log

Activity Log 1

CC ID: 623343
Activity Date/Time: 2016-05-23
Description:

Date that the source FGDC record was last modified.

Activity Log 2

CC ID: 623342
Activity Date/Time: 2017-11-14
Description:

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

Activity Log 3

CC ID: 717638
Activity Date/Time: 2018-02-08
Description:

Partial upload of Positional Accuracy fields only.

Activity Log 4

CC ID: 743744
Activity Date/Time: 2018-03-13
Description:

Partial upload to move data access links to Distribution Info.

Data Quality

Horizontal Positional Accuracy:

Horizontal accuracy can be characterized by the rule of thumb of 1/2000th of flying height or roughly 0.5 meters for this collect. Spot checks in the field routinely are measured at 1/4000th of flying height but are not formally characterized.

Vertical Positional Accuracy:

The vertical accuracy was tested following the National Standards for Spatial Data Accuracy.

Based on a total of 22 points the average error between the bare earth LiDAR coverage and the control was 0.002 m with a root mean

square error (RMSE) of 0.057 m.

Completeness Measure:

Cloud Cover: Unknown

Completeness Report:

LIDAR raster data is visually inspected for completeness to ensure that any gaps between flight lines or loss of

signal represents less than 5% of required collection area. Areas of open water where loss of LIDAR signal is common are corrected

to the best estimate of water level at time of collection. LIDAR is self-illuminating and has minimal cloud penetration capability.

Water vapor in steam plumes or particulates in smoke may cause reflection of LIDAR signals and loss of elevation information beneath

these plumes. Glass structures and roofs may appear transparent to the LIDAR signal and therefore may not register on the reflective

surface. Some asphalt formulations have been shown to absorb topographic LIDAR wavelength energy resulting in "pitting" of roof

surfaces using this material.

Conceptual Consistency:

All LAS formatted LIDAR data are validated using commercial GIS software to ensure proper formatting and

loading before delivery. This validation procedure ensures that data on delivery media is in correct physical format and is readable.

Lineage

Sources

Collection System Calibration

CC ID: 623297
Contact Name: Woolpert LLP
Source Contribution:

Minimizes horizontal error caused by IMU mis-alignment by checking over known range and by comparing positional

results from adjacent flight lines to compute error adjustment function.

| Type of Source Media: Validation Report

LiDAR data collection

CC ID: 623296
Contact Name: Woolpert LLP
Extent Type: Discrete
Extent Start Date/Time: 2004-10-08
Scale Denominator: 3000
Source Contribution:

Raw spatial elevation information | Type of Source Media: DVD-ROM

Process Steps

Process Step 1

CC ID: 623298
Description:

Data Collection: Using a LH Systems ALS50 Light Detection and Ranging (LiDAR) system, 41 flight lines of high

density (submeter ground sample distance) data were collected over areas in coastal Connecticut (approximately 300 square kilometers).

Two returns were recorded for each laser pulse along with an intensity value for each return. The data acquisition occurred in one

(1) mission on October 8, 2004. Three (3) airborne global positioning system (GPS) base stations were used to support the LiDAR data

acquisition: Moriches 1 continuously operating reference station (CORS) ARP, NGS point P36, and one station Woolpert located using

static GPS positioning methods, Madison CP. In addition, twenty-two control points were surveyed through fast-static GPS methods

to support the final accuracy analysis and tied into the National Geodetic Survey (NGS) points Moriches CORS and P36.

Process Date/Time: 2004-10-01 00:00:00

Process Step 2

CC ID: 623299
Description:

Airborne GPS Processing: Airborne GPS data was differentially processed and integrated with the post processed

IMU data to derive a smoothed best estimate of trajectory (SBET). The SBET was used to reduce the LiDAR slant range measurements

to a raw reflective surface for each flight line. The overlap between flight lines was removed to provide a homogeneous coverage,

and the coverage was classified to extract a bare earth digital elevation model (DEM). Airborne GPS is differentially processed

using the GrafNAV V4.10 software by Waypoint Consulting of Calgary, Alberta, Canada. The PDOP and distance separation is as

follows: P36: Maximum PDOP = 3.58 (maximum) Average Distance Separation: 17 km Madison CP: Maximum PDOP = 3.58 (maximum) Average

Distance Separation: 19 km IMU data is processed using the PosPac V4.2 software by Applanix Corporation of Richmond Hill, Ontario,

Canada. The reflective surface is derived using the ALS Post Processor software by Leica Geosystems GIS & Mapping Division of

Atlanta, Georgia. The classification and quality control (QC) of LiDAR data is carried out using a combination of proprietary

software and TerraScan software by Terrasolid Limited of Helsinki, Finland. Two (2) coverages were delivered in the LAS file

format: bare-earth and above ground features.

Process Date/Time: 2004-11-01 00:00:00

Process Step 3

CC ID: 623300
Description:

IMU data Processing: IMU data provides information concerning roll, pitch and yaw of collection platform

during collection event. IMU information allows the pulse vector to be properly placed in 3D space allowing the distance from

the aircraft reference point to be properly positioned on the elevation model surface. IMU data is processed using the PosPac

V4.2 software by Applanix Corporation of Richmond Hill, Ontario, Canada.

Process Date/Time: 2004-11-01 00:00:00

Process Step 4

CC ID: 623301
Description:

Reflective Surface Generation: The reflective surface is derived using the ALS Post Processor software by

Leica Geosystems GIS & Mapping Division of Atlanta, Georgia.

Process Date/Time: 2004-11-01 00:00:00

Process Step 5

CC ID: 623302
Description:

LIDAR Point Classification The classification and quality control (QC) of LiDAR data is carried out using

a combination of proprietary software and TerraScan software by Terrasolid Limited of Helsinki, Finland.

Process Date/Time: 2004-12-01 00:00:00

Process Step 6

CC ID: 623303
Description:

Output LAS Files Random LIDAR points maintained in UTM coordinate system converted to Geographic projection

with units of Decimal Degrees

Process Date/Time: 2005-01-01 00:00:00

Process Step 7

CC ID: 623304
Description:

Transfer to delivery media: Data is transferred from hard-disk to DVD delivery media using a Primera Bravo

DVD/CDROM disc publishing hardware.

Process Date/Time: 2005-01-01 00:00:00

Process Step 8

CC ID: 623305
Description:

The NOAA Office for Coastal Management (OCM) received files in LAS 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. The las files were converted from State Plane coordinates to Geographic coordinates.

2. The las header fields were sorted by latitude and updated.

Process Date/Time: 2006-09-27 00:00:00

Process Step 9

CC ID: 623306
Description:

For data management purposes, the Office for Coastal Management (OCM) converted the data from NAVD88 heights to

ellipsoid heights using Geoid 03.

Process Date/Time: 2008-01-01 00:00:00

Catalog Details

Catalog Item ID: 48168
Metadata Record Created By: Anne Ball
Metadata Record Created: 2017-11-14 14:19+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2019-07-02 15:17+0000
Metadata Record Published: 2018-03-13
Owner Org: OCM
Metadata Publication Status: Published Externally
Do Not Publish?: N
Metadata Next Review Date: 2019-03-14