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Item Identification
Keywords
Physical Location
Data Set Info
Support Roles
Extents
Spatial Info
Access Info
Distribution Info
URLs
Tech Environment
Data Quality
Lineage
Catalog Details

Summary

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Short Citation
OCM Partners, 2024: 2013 Cecil County Lidar, https://www.fisheries.noaa.gov/inport/item/51980.
Full Citation Examples

Abstract

The County of Cecil Maryland requested delivery of three dimensional classified point cloud and contour data derived from LiDAR(Light Detection and Ranging) technology for the entirety of Cecil County, MD. Remotely sensed, geographically referenced elevation measurements were collected by Axis Geospatial, LLC using airborne LiDAR sensors.

Distribution Information

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

  • LAS/LAZ - LASer

    Bulk download of data files in LAZ format, geographic coordinates, orthometric heights.

Access Constraints:

None

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be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions.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.

Controlled Theme Keywords

COASTAL ELEVATION, elevation, TERRAIN ELEVATION

Child Items

No Child Items for this record.

Contact Information

Point of Contact
NOAA Office for Coastal Management (NOAA/OCM)
coastal.info@noaa.gov
(843) 740-1202
https://coast.noaa.gov

Metadata Contact
NOAA Office for Coastal Management (NOAA/OCM)
coastal.info@noaa.gov
(843) 740-1202
https://coast.noaa.gov

Extents

Geographic Area 1

-76.2433° W, -75.7635° E, 39.7225° N, 39.358° S

Time Frame 1
2013-12-20 - 2014-01-20

Item Identification

Title: 2013 Cecil County Lidar
Short Name: 2013 Cecil MD Lidar
Status: Completed
Publication Date: 2015-04-16
Abstract:

The County of Cecil Maryland requested delivery of three dimensional classified point cloud and contour data derived from LiDAR(Light Detection and Ranging) technology for the entirety of Cecil County, MD. Remotely sensed, geographically referenced elevation measurements were collected by Axis Geospatial, LLC using airborne LiDAR sensors.

Purpose:

The purpose of this project was to acquire LiDAR for The County of Cecil Maryland covering the entirety of Cecil County, MD plus 200 feet, to allow the generation of the required topography.

Keywords

Theme Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Science Keywords
EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION
Global Change Master Directory (GCMD) Science Keywords
EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION
ISO 19115 Topic Category
elevation
UNCONTROLLED
None beach
None erosion

Spatial Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Location Keywords
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA
Global Change Master Directory (GCMD) Location Keywords
VERTICAL LOCATION > LAND SURFACE
UNCONTROLLED
Geographic Names Information System Cecil County
Geographic Names Information System Elkton
Geographic Names Information System Maryland
Geographic Names Information System Northeast

Instrument Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Instrument Keywords
LIDAR > Light Detection and Ranging

Platform Keywords

Thesaurus Keyword
Global Change Master Directory (GCMD) Platform Keywords
Airplane > Airplane

Physical Location

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

Data Set Information

Data Set Scope Code: Data Set
Data Set Type: Elevation
Maintenance Frequency: None Planned
Data Presentation Form: binary point cloud
Entity Attribute Detail Citation:

The attributes and classifications met contract specifications.

Distribution Liability:

The data represents the results of data collection/processing for this specific project and describes the general existing condition on the ground at the time of the acquisition. As such the data is only valid for its intended use, content, time, accuracy, and scale specifications. The user is responsible for the results of any application of the data for other than its intended purpose.

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

Data Set Credit: Axis Geospatial; Cecil County MD

Support Roles

Data Steward

CC ID: 739161
Date Effective From: 2018
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: 739162
Date Effective From: 2018
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: 739163
Date Effective From: 2018
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: 739164
Date Effective From: 2018
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: 1140846
W° Bound: -76.2433
E° Bound: -75.7635
N° Bound: 39.7225
S° Bound: 39.358

Extent Group 1 / Time Frame 1

CC ID: 1140845
Time Frame Type: Range
Start: 2013-12-20
End: 2014-01-20

Spatial Information

Spatial Resolution

Vertical Distance: 0.46 Meter

Spatial Representation

Representations Used

Vector: Yes

Access Information

Security Class: Unclassified
Data Access Procedure:

Data is available online for custom downloads

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: 739168
Start Date: 2018
End Date: Present
Download URL: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=8490
Distributor:
File Name: Customized Download
Description:

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

Compression: Zip

Distribution 2

CC ID: 739169
Start Date: 2018
End Date: Present
Download URL: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/8490/index.html
Distributor:
File Name: Bulk Download
Description:

Bulk download of data files in LAZ format, geographic coordinates, orthometric heights.

File Type (Deprecated): LAZ
Distribution Format: LAS/LAZ - LASer
Compression: Zip

URLs

URL 1

CC ID: 739156
URL: https://coast.noaa.gov/
Name: NOAA's Office for Coastal Management (OCM) website
URL Type:
Online Resource
File Resource Format: HTML
Description:

Information on the NOAA Office for Coastal Management (OCM)

URL 2

CC ID: 739157
URL: https://coast.noaa.gov/dataviewer/#/
Name: NOAA's Office for Coastal Management (OCM) Data Access Viewer (DAV)
URL Type:
Online Resource
File Resource Format: HTML
Description:

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.

URL 3

CC ID: 739158
URL: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/8490/supplemental/2013_cecil_area.kmz
Name: Browse graphic
URL Type:
Browse Graphic
File Resource Format: KML
Description:

This graphic displays the footprint for this lidar data set.

Technical Environment

Description:

Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1

Data Quality

Horizontal Positional Accuracy:

This data meets RMSEr <50 cm

Vertical Positional Accuracy:

Axis Geospatial, LLC located a total of 58 check points for use in the analysis of the lidar data quality. The points were located on relatively flat terrain on surfaces that generally consisted of grass, gravel, or bare earth. The final vertical accuracy (RMSEz x 1.96) of the following landcover types were tested; Bare Earth-FVA (Fundamental Vertical Accuracy), CVA (Consolidated Vertical Accuracy), Crop/Weeds SVA (Supplemental Vertical Accuracy), and Wooded SVA (Supplemental Vertical Accuracy).

The final results for FVA (based on 24 points) was found to be 0.17 feet (0.052 meters);

SVA Crop/Weeds (based on 10 points) was found to be 0.27 feet;

and SVA Woods (based on 24 points) was found to be 0.52 feet. The CVA was found to be .37 feet.

Completeness Report:

The data covers the Cecil County LiDAR project area located in Cecil County, Maryland. The project area includes the towns of Elkton and Northeast. The project area is bounded by the Chesapeake Bay and Susquehanna River on the western side, State of Delaware to the East, and the State of Pennsylvania to the North. The total project acquisition area covers 473 square miles.

Conceptual Consistency:

Data for the Cecil County LiDAR project was visually inspected by Axis Geospatial, LLC for both vertical and horizontal accuracy. Checks are done to ensure that the data is seamless from one tile to the next before being combined and the project requirements have been met across the entire project area. All data are seamless from one tile to the next, containing no gaps or "no data" areas.

Lineage

Process Steps

Process Step 1

CC ID: 1140838
Description:

Using a Trimble Harrier 68i High Definition LiDAR sensor on board a Cessna 206, 191 flight lines of high-density data were collected during 15 separate missions, flown as close together as the weather conditions permitted, to ensure consistent ground conditions across the project area, at a nominal pulse spacing (NPS) of 0.46 m achieved a point density of 4.73 ppm2, were collected by Axis Geospatial, LLC covering Cecil County, MD (approximately 473 square miles). Data Acquisition Height = 2,034 feet Above Ground Level (AGL) - Aircraft Speed = 116 Knots. Multiple returns were recorded for each laser pulse along with an intensity value for each return. A total of 15 missions were flown from December 20, 2013 to January 20, 2014. The presence of a strong CORS (Continuously Operating Reference Station) configuration allowed for the LiDAR to be acquired with Global Navigation Satellite System (GNSS) techniques and procedures. 58 ground control points were surveyed through RTK and static methods. The GEOID used to reduce satellite-derived elevations to orthometric heights was GEOID12A. Data for the task order is referenced to the Maryland State Plane, North American Datum of 1983 (NAD83), and North American Vertical Datum of 1988 (NAVD88), in US Survey Feet. Airborne GPS data was differentially processed and integrated with the post-processed inertial measurement unit (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 coverage was classified to extract a bare earth digital elevation model (DEM) and separate last returns.

Process Date/Time: 2013-02-14 00:00:00

Process Step 2

CC ID: 1140839
Description:

During the project data acquisition by Axis Geospatial, LLC, East-West cross flights were flown over each of the 6 delivery block areas in order to tie the data together from multi-day North-South collections.

Process Date/Time: 2013-02-14 00:00:00

Process Step 3

CC ID: 1140840
Description:

Once the data acquisition and GPS processing phases are complete, the lidar data were processed immediately by Axis Geospatial, LLC to verify the coverage had no voids. The GPS and IMU data were post-processed using ApplanixPOSPac v.6.1 software to derive a best estimate of trajectory. The quality of the solution was verified to be consistent with the accuracy requirements of the project.

Process Date/Time: 2013-02-14 00:00:00

Process Step 4

CC ID: 1140841
Description:

The individual flight lines were inspected by Axis Geospatial, LLC to ensure the systematic and residual errors have been identified and removed. Then, the flight lines were compared to adjacent flight lines for any mismatches to obtain a homogenous coverage throughout the project area. Axis Geospatial, LLC compared LiDAR intensity values against known control point locations that were on defineable features such as the end of a paint line and measured the apparent offsets; these values were then averaged to come up with the X and Y values used for the horizontal correction. Additionally Axis Geospatial, LLC compared a TIN (Triangulated Irregular Network) of LiDAR points within 25 feet of each surveyed control point and measured the apparent vertical offsets; these values were then averaged to come up with the Z value used for the vertical correction. Next the point cloud underwent a classification process to determine bare-earth points and non-ground points utilizing TerraSolid, TerraScanLiDAR processing and modeling software. v. 014.013. This process determined Default (Class 1), Ground (Class 2), and Noise (Class 7), classifications. The bare-earth (Class 2 - Ground) lidar points underwent a manual QA/QC step to verify that artifacts have been removed from the bare-earth surface. The surveyed ground control points are used to perform the accuracy checks and statistical analysis of the lidar dataset.

Process Date/Time: 2014-12-31 00:00:00

Process Step 5

CC ID: 1140842
Description:

Applanix software (PosPAC MMS) was used in the post processing of the airborne GPS and inertial data, which are critical to the positioning and orientation of the sensor during all flights. POSPac MMS provides the smoothed best estimate of trajectory (SBET) that is necessary for the post processor to develop the point cloud from the lidar missions. The point cloud is the mathematical three-dimensional collection of all returns from all laser pulses as determined from the aerial mission. The GEOID used to reduce satellite derived elevations to orthometric heights was GEOID12A. Data for the task order is referenced to the Maryland State Plane, NAD83, and NAVD88, in US Survey Feet. At this point the data are ready for analysis, classification, and filtering to generate a bare-earth surface model in which the above ground features are removed from the data set. The point cloud was manipulated by the Trimble LPMaster software; GeoCue, TerraScan, and TerraModeler software were used for the automated data classification, manual cleanup, and bare-earth generation from the data. Project specific macros were used to classify the ground.

All data were manually reviewed and any remaining artifacts removed using functionality provided by TerraScan and TerraModeler.

Data were then run through additional macros to ensure deliverable classification levels matching the ASPRS LAS Version 1.2 Classification structure. GeoCue functionality was then used to ensure correct LAS Versioning. In-house software was used as a final QA/QC check to provide LAS Analysis of the delivered tiles. QA/QC checks were performed on a per tile level to verify final classification metrics and full LAS header information.

Axis Geospatial, LLC located a total of 58 check points for use in the analysis of the lidar data quality. The points were located on relatively flat terrain on surfaces that generally consisted of grass, gravel, or bare earth. The final vertical accuracy (RMSEz x 1.96) of the following landcover types were tested; Bare Earth-FVA (Fundamental Vertical Accuracy), CVA (Consolidated Vertical Accuracy), Crop/Weeds SVA (Supplemental Vertical Accuracy), and Wooded SVA (Supplemental Vertical Accuracy). The final results for FVA (based on 24 points) was found to be 0.17 feet; SVA Crop/Weeds (based on 10 points) was found to be 0.27 feet; and SVA Woods (based on 24 points) was found to be 0.52 feet. The CVA was found to be .37 feet.

Process Date/Time: 2014-12-31 00:00:00

Process Step 6

CC ID: 1140843
Description:

NOAA OCM downloaded the data from Maryland iMap (imap.maryland.gov) in October 2017. Data were converted from Maryland State Plane (1900) with NAVD88 (geoid12a) vertical feet to geographic coordinates with height above the ellipsoid in vertical meters. Data were ingested into the Digital Coast Data Access Viewer for custom distribution.

Process Date/Time: 2018-03-08 00:00:00
Process Contact: Office for Coastal Management (OCM)

Catalog Details

Catalog Item ID: 51980
GUID: gov.noaa.nmfs.inport:51980
Metadata Record Created By: Kirk Waters
Metadata Record Created: 2018-03-08 06:38+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2023-10-17 16:12+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