spatialRepresentationInfo
referenceSystemInfo
referenceSystemInfo
referenceSystemInfo
identificationInfo
contentInfo
distributionInfo
dataQualityInfo

2014 Baltimore County Lidar
 (MI_Metadata)
    fileIdentifier:  gov.noaa.nmfs.inport:51983
    language:
      LanguageCode:  eng
    characterSet:  (MD_CharacterSetCode) UTF8
    hierarchyLevel:  (MD_ScopeCode) dataset
    hierarchyLevelName:  Elevation
    contact:  (CI_ResponsibleParty)
        organisationName:  OCM Partners
        contactInfo:  (CI_Contact)
            phone:  (CI_Telephone)
                voice: (missing)
            address:  (CI_Address)
        role:  (CI_RoleCode) resourceProvider
    contact:  (CI_ResponsibleParty)
        organisationName:  NOAA Office for Coastal Management
        contactInfo:  (CI_Contact)
            phone:  (CI_Telephone)
                voice:  (843) 740-1202
            address:  (CI_Address)
                deliveryPoint:  2234 South Hobson Ave
                city:  Charleston
                administrativeArea:  SC
                postalCode:  29405-2413
                country: (missing)
                electronicMailAddress:  coastal.info@noaa.gov
            onlineResource:  (CI_OnlineResource)
                linkage: https://coast.noaa.gov
                protocol:  WWW:LINK-1.0-http--link
                name:  NOAA Office for Coastal Management Website
                description:  NOAA Office for Coastal Management Home Page
                function:  (CI_OnLineFunctionCode) information
        role:  (CI_RoleCode) pointOfContact
    dateStamp:
      DateTime:  2023-05-30T18:10:31
    metadataStandardName:  ISO 19115-2 Geographic Information - Metadata Part 2 Extensions for imagery and gridded data
    metadataStandardVersion:  ISO 19115-2:2009(E)
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    spatialRepresentationInfo:
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    referenceSystemInfo:
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      referenceSystemInfo:  (MD_ReferenceSystem)
          referenceSystemIdentifier:  (RS_Identifier)
              authority:  (CI_Citation)
                  title:  NAD83(2011)
                  date:  (CI_Date)
                      date:  2008-11-12
                      dateType:  (CI_DateTypeCode) publication
                  citedResponsibleParty:  (CI_ResponsibleParty)
                      organisationName:  European Petroleum Survey Group
                      contactInfo:  (CI_Contact)
                          onlineResource:  (CI_OnlineResource)
                              linkage: https://apps.epsg.org/api/v1/CoordRefSystem/6318/export/?format=gml
                      role: (missing)
              code:  urn:ogc:def:crs:EPSG:6318
              version:  6.18.3
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      referenceSystemInfo:  (MD_ReferenceSystem)
          referenceSystemIdentifier:  (RS_Identifier)
              authority:  (CI_Citation)
                  title:  North American Vertical Datum of 1988 (NAVD88) (GEOID18) meters
                  alternateTitle:  North American Vertical Datum of 1988 (NAVD88) (GEOID18) meters
                  citedResponsibleParty:  (CI_ResponsibleParty)
                      organisationName: (withheld)
                      contactInfo:  (CI_Contact)
                          onlineResource:  (CI_OnlineResource)
                              linkage: https://apps.epsg.org/api/v1/VerticalCoordRefSystem/5703/?api_key=gml
                              name:  North American Vertical Datum of 1988 (NAVD88) (GEOID18) meters
                              description:  Link to Geographic Markup Language (GML) description of reference system.
                              function:  (CI_OnLineFunctionCode) information
                      role:  (CI_RoleCode) resourceProvider
                  citedResponsibleParty:  (CI_ResponsibleParty)
                      organisationName:  European Petroleum Survey Group
                      contactInfo:  (CI_Contact)
                          onlineResource:  (CI_OnlineResource)
                              linkage: https://www.epsg.org/
                              name:  European Petroleum Survey Group Geodetic Parameter Registry
                              description:  Registry that accesses the EPSG Geodetic Parameter Dataset, which is a structured dataset of Coordinate Reference Systems and Coordinate Transformations.
                              function:  (CI_OnLineFunctionCode) search
                      role:  (CI_RoleCode) publisher
                  VerticalCS:
                    metaDataProperty:
                      CommonMetaData:
                        type:  vertical
                        informationSource:  OGP
                        revisionDate:  2006-11-28
                        isDeprecated:  false
                    identifier:  urn:ogc:def:cs:EPSG::6499
                    name:  Vertical CS. Axis: height (H). Orientation: up. UoM: meter.
                    remarks:  Used in vertical coordinate reference systems.
                    axis:
                      CoordinateSystemAxis:
                        descriptionReference:  urn:ogc:def:axis-name:EPSG::9904
                        identifier:  urn:ogc:def:axis:EPSG::114
                        axisAbbrev:  H
                        axisDirection:  up
              code:  urn:ogc:def:crs:EPSG::5703
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    identificationInfo:  (MD_DataIdentification)
        citation:  (CI_Citation)
            title:  2014 Baltimore County Lidar
            date:  (CI_Date)
                date:  2015-04
                dateType:  (CI_DateTypeCode) publication
            identifier:  (MD_Identifier)
                authority:  (CI_Citation)
                    title:  NOAA/NMFS/EDM
                    date: (inapplicable)
                code:
                  Anchor:  InPort Catalog ID 51983
            citedResponsibleParty:  (CI_ResponsibleParty)
                organisationName: (inapplicable)
                contactInfo:  (CI_Contact)
                    onlineResource:  (CI_OnlineResource)
                        linkage: https://www.fisheries.noaa.gov/inport/item/51983
                        protocol:  WWW:LINK-1.0-http--link
                        name:  Full Metadata Record
                        description:  View the complete metadata record on InPort for more information about this dataset.
                        function:  (CI_OnLineFunctionCode) information
                role: (inapplicable)
            citedResponsibleParty:  (CI_ResponsibleParty)
                organisationName: (inapplicable)
                contactInfo:  (CI_Contact)
                    onlineResource:  (CI_OnlineResource)
                        linkage: https://coast.noaa.gov/
                        protocol:  WWW:LINK-1.0-http--link
                        name:  NOAA's Office for Coastal Management (OCM) website
                        description:  Information on the NOAA Office for Coastal Management (OCM)
                        function:  (CI_OnLineFunctionCode) download
                role: (inapplicable)
            citedResponsibleParty:  (CI_ResponsibleParty)
                organisationName: (inapplicable)
                contactInfo:  (CI_Contact)
                    onlineResource:  (CI_OnlineResource)
                        linkage: https://imap.Maryland.gov
                        protocol:  WWW:LINK-1.0-http--link
                        name:  Maryland iMAP
                        description:  Original source for the point clouds.
                        function:  (CI_OnLineFunctionCode) download
                role: (inapplicable)
            citedResponsibleParty:  (CI_ResponsibleParty)
                organisationName: (inapplicable)
                contactInfo:  (CI_Contact)
                    onlineResource:  (CI_OnlineResource)
                        linkage: https://coast.noaa.gov/dataviewer/#/
                        protocol:  WWW:LINK-1.0-http--link
                        name:  NOAA's Office for Coastal Management (OCM) Data Access Viewer (DAV)
                        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.
                        function:  (CI_OnLineFunctionCode) download
                role: (inapplicable)
            presentationForm: (unknown)
        abstract:  Aerial Cartographics of America (ACA) collected 750 square miles covering Baltimore County. The nominal pulse spacing for this project was 1 point every 0.7 meters. Dewberry used proprietary procedures to classify the LAS according to project specifications: 0-Never Classified, 1-Unclassified, 2-Ground, 7-Low Noise, 9-Water, 10-Ignored Ground due to breakline proximity. Dewberry produced 3D breaklines and combined these with the final LiDAR data to produce seamless hydro-conditioned DEMs for the project area. The data was formatted according to the Baltimore County tile naming convention. This data set is an LAZ (compressed LAS) format file containing LIDAR point cloud data.
        purpose:  The purpose of this LiDAR data was to produce high accuracy 3D elevation products, including tiled LiDAR in LAS 1.2 format, 3D breaklines, and 1 meter cell size hydroconditioned Digital Elevation Models (DEMs). All products follow and comply with Baltimore County Lidar specifications
        credit:  Baltimore County Office of Information Technology The custom download may be cited as National Oceanic and Atmospheric Administration (NOAA) Digital Coast Data Access Viewer. Charleston, SC: NOAA Office for Coastal Management. Accessed Jul 01, 2023 at https://coast.noaa.gov/dataviewer.
        status:  (MD_ProgressCode) completed
        pointOfContact:  (CI_ResponsibleParty)
            organisationName:  NOAA Office for Coastal Management
            contactInfo:  (CI_Contact)
                phone:  (CI_Telephone)
                    voice:  (843) 740-1202
                address:  (CI_Address)
                    deliveryPoint:  2234 South Hobson Ave
                    city:  Charleston
                    administrativeArea:  SC
                    postalCode:  29405-2413
                    country: (missing)
                    electronicMailAddress:  coastal.info@noaa.gov
                onlineResource:  (CI_OnlineResource)
                    linkage: https://coast.noaa.gov
                    protocol:  WWW:LINK-1.0-http--link
                    name:  NOAA Office for Coastal Management Website
                    description:  NOAA Office for Coastal Management Home Page
                    function:  (CI_OnLineFunctionCode) information
            role:  (CI_RoleCode) pointOfContact
        pointOfContact:  (CI_ResponsibleParty)
            organisationName:  NOAA Office for Coastal Management
            contactInfo:  (CI_Contact)
                phone:  (CI_Telephone)
                    voice:  (843) 740-1202
                address:  (CI_Address)
                    deliveryPoint:  2234 South Hobson Ave
                    city:  Charleston
                    administrativeArea:  SC
                    postalCode:  29405-2413
                    country: (missing)
                    electronicMailAddress:  coastal.info@noaa.gov
                onlineResource:  (CI_OnlineResource)
                    linkage: https://coast.noaa.gov
                    protocol:  WWW:LINK-1.0-http--link
                    name:  NOAA Office for Coastal Management Website
                    description:  NOAA Office for Coastal Management Home Page
                    function:  (CI_OnLineFunctionCode) information
            role:  (CI_RoleCode) custodian
        resourceMaintenance:  (MD_MaintenanceInformation)
            maintenanceAndUpdateFrequency:  (MD_MaintenanceFrequencyCode) asNeeded
        graphicOverview:  (MD_BrowseGraphic)
            fileName: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/8492/supplemental/2015_Baltimore_county_area.kmz
            fileDescription:  This graphic displays the footprint for this lidar data set.
            fileType:  KML
        descriptiveKeywords:  (MD_Keywords)
            keyword:  EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION
            keyword:  EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION
            type:  (MD_KeywordTypeCode) theme
            thesaurusName:  (CI_Citation)
                title:  Global Change Master Directory (GCMD) Science Keywords
                date: (missing)
                edition:  12.3
        descriptiveKeywords:  (MD_Keywords)
            keyword:  CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > MARYLAND
            keyword:  VERTICAL LOCATION > LAND SURFACE
            type:  (MD_KeywordTypeCode) place
            thesaurusName:  (CI_Citation)
                title:  Global Change Master Directory (GCMD) Location Keywords
                date: (missing)
                edition:  12.3
        descriptiveKeywords:  (MD_Keywords)
            keyword:  LIDAR > Light Detection and Ranging
            type:  (MD_KeywordTypeCode) instrument
            thesaurusName:  (CI_Citation)
                title:  Global Change Master Directory (GCMD) Instrument Keywords
                date: (missing)
                edition:  14.9
        descriptiveKeywords:  (MD_Keywords)
            keyword:  Airplane > Airplane
            type:  (MD_KeywordTypeCode) platform
            thesaurusName:  (CI_Citation)
                title:  Global Change Master Directory (GCMD) Platform Keywords
                date: (missing)
                edition:  14.9
        descriptiveKeywords:  (MD_Keywords)
            keyword:  Contours
            keyword:  beach
            keyword:  erosion
            type:  (MD_KeywordTypeCode) theme
        descriptiveKeywords:  (MD_Keywords)
            keyword:  Lidar - partner (no harvest)
            type:  (MD_KeywordTypeCode) project
            thesaurusName:  (CI_Citation)
                title:  InPort
                date: (inapplicable)
        resourceConstraints:  (MD_LegalConstraints)
            useConstraints:  (MD_RestrictionCode) otherRestrictions
            otherConstraints:  Cite As: OCM Partners, [Date of Access]: 2014 Baltimore County Lidar [Data Date Range], https://www.fisheries.noaa.gov/inport/item/51983.
        resourceConstraints:  (MD_Constraints)
            useLimitation:  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.
        resourceConstraints:  (MD_LegalConstraints)
            accessConstraints:  (MD_RestrictionCode) otherRestrictions
            useConstraints:  (MD_RestrictionCode) otherRestrictions
            otherConstraints:  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. | Distribution Liability: This data was produced for Baltimore County according to specific project requirements. This information is provided "as is". Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners
        resourceConstraints:  (MD_SecurityConstraints)
            classification:  (MD_ClassificationCode) unclassified
            classificationSystem: (missing)
            handlingDescription: (missing)
        aggregationInfo:  (MD_AggregateInformation)
            aggregateDataSetName:  (CI_Citation)
                title:  NOAA Data Management Plan (DMP)
                date: (unknown)
                identifier:  (MD_Identifier)
                    authority:  (CI_Citation)
                        title:  NOAA/NMFS/EDM
                        date: (inapplicable)
                    code:  51983
                citedResponsibleParty:  (CI_ResponsibleParty)
                    organisationName: (inapplicable)
                    contactInfo:  (CI_Contact)
                        onlineResource:  (CI_OnlineResource)
                            linkage: https://www.fisheries.noaa.gov/inportserve/waf/noaa/nos/ocmp/dmp/pdf/51983.pdf
                            protocol:  WWW:LINK-1.0-http--link
                            name:  NOAA Data Management Plan (DMP)
                            description:  NOAA Data Management Plan for this record on InPort.
                            function:  (CI_OnLineFunctionCode) information
                    role: (inapplicable)
            associationType:  (DS_AssociationTypeCode) crossReference
        spatialRepresentationType:  (MD_SpatialRepresentationTypeCode) vector
        spatialResolution:  (MD_Resolution)
            distance:
              Distance:  .7
        language:  eng; US
        topicCategory:  (MD_TopicCategoryCode) elevation
        environmentDescription:  Microsoft Windows 7 Enterprise Service Pack 1; ESRI ArcCatalog 10.1
        extent:  (EX_Extent)
            geographicElement:  (EX_GeographicBoundingBox)
                westBoundLongitude:  -76.914808
                eastBoundLongitude:  -76.33876
                southBoundLatitude:  39.193934
                northBoundLatitude:  39.722331
            temporalElement:  (EX_TemporalExtent)
                extent:
                  TimePeriod:
                    description:   | Currentness: Ground Condition
                    beginPosition:  2014-05-06
                    endPosition:  2014-05-07
        supplementalInformation:  A complete description of this dataset is available in the Final Project Report that was submitted to Baltimore County
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    contentInfo:  (MD_FeatureCatalogueDescription)
        complianceCode:  false
        language:
          LanguageCode:  eng
        includedWithDataset:  false
        featureCatalogueCitation:  (CI_Citation)
            title:  none
            date: (unavailable)
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    distributionInfo:  (MD_Distribution)
        distributionFormat:  (MD_Format)
            name:  Zip
            version: (missing)
            fileDecompressionTechnique:  Zip
        distributionFormat:  (MD_Format)
            name:  LAZ
            version: (missing)
        distributor:  (MD_Distributor)
            distributorContact:  (CI_ResponsibleParty)
                organisationName:  NOAA Office for Coastal Management
                contactInfo:  (CI_Contact)
                    phone:  (CI_Telephone)
                        voice:  (843) 740-1202
                    address:  (CI_Address)
                        deliveryPoint:  2234 South Hobson Ave
                        city:  Charleston
                        administrativeArea:  SC
                        postalCode:  29405-2413
                        country: (missing)
                        electronicMailAddress:  coastal.info@noaa.gov
                    onlineResource:  (CI_OnlineResource)
                        linkage: https://coast.noaa.gov
                        protocol:  WWW:LINK-1.0-http--link
                        name:  NOAA Office for Coastal Management Website
                        description:  NOAA Office for Coastal Management Home Page
                        function:  (CI_OnLineFunctionCode) information
                role:  (CI_RoleCode) distributor
        transferOptions:  (MD_DigitalTransferOptions)
            onLine:  (CI_OnlineResource)
                linkage: https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=8492
                protocol:  WWW:LINK-1.0-http--link
                name:  Customized Download
                description:  Create custom data files by choosing data area, product type, map projection, file format, datum, etc.
                function:  (CI_OnLineFunctionCode) download
        transferOptions:  (MD_DigitalTransferOptions)
            onLine:  (CI_OnlineResource)
                linkage: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid18/8492/index.html
                protocol:  WWW:LINK-1.0-http--link
                name:  Bulk Download
                description:  Bulk download of data files in LAZ format, geographic coordinates, orthometric heights.
                function:  (CI_OnLineFunctionCode) download
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    dataQualityInfo:  (DQ_DataQuality)
        scope:  (DQ_Scope)
            level:  (MD_ScopeCode) dataset
        report:  (DQ_AbsoluteExternalPositionalAccuracy)
            nameOfMeasure:  Horizontal Positional Accuracy
            evaluationMethodDescription:  Only checkpoints photo-identifiable in the intensity imagery can be used to test the horizontal accuracy of the LiDAR. Photo-identifiable checkpoints in intensity imagery typically include checkpoints located at the ends of paint stripes on concrete or asphalt surfaces or checkpoints located at 90 degree corners of different reflectivity, e.g. a sidewalk corner adjoining a grass surface. The xy coordinates of checkpoints, as defined in the intensity imagery, are compared to surveyed xy coordinates for each photo-identifiable checkpoint. These differences are used to compute the tested horizontal accuracy of the LiDAR. As not all projects contain photo-identifiable checkpoints, the horizontal accuracy of the LiDAR cannot always be tested. Qualitative value: 66 cm, Test that produced the valued: Lidar vendors calibrate their lidar systems during installation of the system and then again for every project acquired. Typical calibrations include cross flights that capture features from multiple directions that allow adjustments to be performed so that the captured features are consistent between all swaths and cross flights from all directions. Dewberry tested the horizontal accuracy of the LiDAR by comparing photo-identifiable survey checkpoints to the LiDAR Intensity Imagery. As only thirteen (13) checkpoints were photo-identifiable, the results are not statistically significant enough to report as a final tested value but the results of this testing are shown below. Using NSSDA methodology (endorsed by the ASPRS Positional Accuracy Standards for Digital Geospatial Data (2014)), horizontal accuracy at the 95% confidence level (called ACCURACYr) is computed by the formula RMSEr * 1.7308 or RMSExy * 2.448. Actual positional accuracy of this dataset was found to be RMSEx = 27 cm and RMSEy = 27 cm which equates to +/- 66 cm at 95% confidence level.
            result: (missing)
        report:  (DQ_AbsoluteExternalPositionalAccuracy)
            nameOfMeasure:  Vertical Positional Accuracy
            evaluationMethodDescription:  The vertical accuracy of the source LiDAR and final bare earth DEMs was tested by Dewberry with 104 independent survey checkpoints. The survey checkpoints are evenly distributed throughout the project area and are located in areas of non-vegetated terrain, including bare earth, open terrain, and urban terrain (41), and vegetated terrain, including forest, brush, tall weeds, crops, and high grass (63). The vertical accuracy of the LiDAR is tested by comparing survey checkpoints to a triangulated irregular network (TIN) that is created from the LiDAR ground points. Checkpoints are always compared to interpolated surfaces created from the LiDAR point cloud because it is unlikely that a survey checkpoint will be located at the location of a discrete LiDAR point. The vertical accuracy of the final bare earth DEMs is tested by extracting the elevation of the pixel that contains the x/y coordinates of the checkpoint and comparing these DEM elevations to the surveyed elevations. Accuracy results may vary between the source LiDAR and final DEM deliverable. DEMs are created by averaging several LiDAR points within each pixel which may result in slightly different elevation values at each survey checkpoint when compared to the source LAS, which is tested by comparing survey checkpoints to TINs. TINs do not average several LiDAR points together but interpolate (linearly) between two or three points to derive an elevation value. The accuracy results reported for the overall project are the accuracy results of the source LiDAR. Bare earth DEM accuracy results are reported in the DEM metadata file. All checkpoints located in non-vegetated terrain were used to compute the Non-vegetated Vertical Accuracy (NVA). Project specifications required a NVA of 19.6 cm at the 95% confidence level based on RMSEz (10 cm) x 1.9600. All checkpoints located in vegetated terrain were used to compute the Vegetated Vertical Accuracy (VVA). Project specifications required a VVA of 30 cm based on the 95th percentile.Qualitative value:13.3 cm 19.0 cm, Test that produced the value: The following result is from testing the source LiDAR data. DEM accuracy results are in the DEM metadata file. This LiDAR dataset was tested to meet ASPRS Positional Accuracy Standards for Digital Geospatial Data (2014) for a 10 cm RMSEz Vertical Accuracy Class. Actual NVA accuracy was found to be RMSEz =6.79 cm, equating to +/- 13.3 cm at 95% confidence level. The following result is from testing the source LiDAR data. DEM accuracy results are in the DEM metadata file. This LiDAR dataset was tested to meet ASPRS Positional Accuracy Standards for Digital Geospatial Data (2014) for a 10 cm RMSEz Vertical Accuracy Class. Actual VVA accuracy was found to be +/- 19.0 cm at the 95th percentile. The 5% outliers consisted of 6 checkpoints that are larger than the 95th percentile. These checkpoints have DZ values ranging between 19.2 cm and 23.7 cm.
            result: (missing)
        report:  (DQ_CompletenessCommission)
            nameOfMeasure:  Completeness Report
            evaluationMethodDescription:  A visual qualitative assessment was performed to ensure data completeness and bare earth data cleanliness. No void or missing data and data passes vertical accuracy specifications.
            result: (missing)
        report:  (DQ_ConceptualConsistency)
            nameOfMeasure:  Conceptual Consistency
            evaluationMethodDescription:  Data covers the tile scheme provided for the project area.
            result: (missing)
        lineage:  (LI_Lineage)
            statement: (missing)
            processStep:  (LI_ProcessStep)
                description:  Data for the Baltimore County Lidar project was acquired by Aerial Cartogrpahics of America (ACA). The project area included approximately 750 contiguous square miles covering baltimore county. LiDAR sensor data were collected with the Reigle 680i. The data was delivered in Maryland State Plane Corrdinate System, US Feet, horizontal datum NAD83, vertical datum NAVD88, Geoid 09. Deliverables for the project included a raw (unclassified) calibrated LiDAR point cloud, hydroconditioned DEMs, DSMs, intensity imagery, and breakline data. The calibration process considered all errors inherent with the equipment including errors in GPS, IMU, and sensor specific parameters. Adjustments were made to achieve a flight line to flight line data match (relative calibration) and subsequently adjusted to control for absolute accuracy. Process steps to achieve this are as follows: Rigorous LiDAR calibration: all sources of error such as the sensor's ranging and torsion parameters, atmospheric variables, GPS conditions, and IMU offsets were analyzed and removed to the highest level possible. This method addresses all errors, both vertical and horizontal in nature. Ranging, atmospheric variables, and GPS conditions affect the vertical position of the surface, whereas IMU offsets and torsion parameters affect the data horizontally. The horizontal accuracy is proven through repeatability: when the position of features remains constant no matter what direction the plane was flying and no matter where the feature is positioned within the swath, relative horizontal accuracy is achieved. Absolute horizontal accuracy is achieved through the use of differential GPS with base lines shorter than 25 miles. The base station is set at a temporary monument that is 'tied-in' to the CORS network. The same position is used for every lift, ensuring that any errors in its position will affect all data equally and can therefore be removed equally. Vertical accuracy is achieved through the adjustment to ground control survey points within the finished product. Although the base station has absolute vertical accuracy, adjustments to sensor parameters introduces vertical error that must be normalized in the final (mean) adjustment.
            processStep:  (LI_ProcessStep)
                description:  Dewberry utilizes a variety of software suites for inventory management, classification, and data processing. All LiDAR related processes begin by importing the data into the GeoCue task management software. The swath data is tiled according to project specifications. The tiled data is then opened in Terrascan where Dewberry classifies edge of flight line points that may be geometrically unusable to a separate class. These points are separated from the main point cloud so that they are not used in the ground algorithms. Dewberry then uses proprietary ground classification routines to remove any non-ground points and generate an accurate ground surface. The ground routine consists of three main parameters (building size, iteration angle, and iteration distance); by adjusting these parameters and running several iterations of this routine an initial ground surface is developed. The building size parameter sets a roaming window size. Each tile is loaded with neighboring points from adjacent tiles and the routine classifies the data section by section based on this roaming window size. The second most important parameter is the maximum terrain angle, which sets the highest allowed terrain angle within the model. As part of the ground routine, low noise points are classified to class 7. Once the ground routine has been completed, bridge decks are classified to class 17 using bridge breaklines compiled by Dewberry. A manual quality control routine is then performed using hillshades, cross-sections, and profiles within the Terrasolid software suite. After this QC step, a peer review is performed on all tiles and a supervisor manual inspection is completed on a percentage of the classified tiles based on the project size and variability of the terrain. After the ground classification and bridge deck corrections are completed, the dataset is processed through a water classification routine that utilizes breaklines compiled by Dewberry to automatically classify hydrographic features. The water classification routine selects ground points within the breakline polygons and automatically classifies them as class 9, water. During this water classification routine, points that are within 1x NPS or less of the hydrographic features are moved to class 10, an ignored ground due to breakline proximity. Overage points are then identified in Terrascan and GeoCue is used to set the overlap bit for the overage points and the withheld bit is set on the withheld points previously identified in Terrascan before the ground classification routine was performed. A final QC is performed on the data. T The data was classified as follows: Class 1 = Unclassified. This class includes vegetation, buildings, noise etc. Class 2 = Ground Class 7= Low Noise Class 9 = Water Class 10 = Ignored Ground due to breakline proximity The LAS header information was verified to contain the following: Class (Integer) Adjusted GPS Time (0.0001 seconds) Easting (0.003 m) Northing (0.003 m) Elevation (0.003 m) Echo Number (Integer) Echo (Integer) Intensity (16 bit integer) Flight Line (Integer) Scan Angle (degree)
                dateTime:
                  DateTime:  2014-08-01T00:00:00
            processStep:  (LI_ProcessStep)
                description:  NOAA OCM downloaded the point cloud data from the Maryland iMAP (imap.maryland.gov) in October, 2017. Data were reprojected to geographic coordinates and vertically transformed to ellipsoid heights in meters using the Geoid12a model for ingest into the Digital Coast Data Access Viewer. Classifications were found to not completely agree with the descriptions in steps 1 and 2 above. Only classes 1,2,7,9, and 17 are in the data set. The data set is listed on the iMAP site as 2015, but the collection was in 2014 according to the original metadata and the time stamps in the point cloud.
                dateTime:
                  DateTime:  2018-03-09T00:00:00
                processor:  (CI_ResponsibleParty)
                    organisationName:  Office for Coastal Management
                    role:  (CI_RoleCode) processor
            source:  (LI_Source)
                sourceCitation:  (CI_Citation)
                    title:  Maryland iMAP data
                    date: (missing)
                    citedResponsibleParty:  (CI_ResponsibleParty)
                        organisationName:  Maryland iMAP
                        contactInfo:  (CI_Contact)
                            onlineResource:  (CI_OnlineResource)
                                linkage: https://imap.maryland.gov
                                protocol:  WWW:LINK-1.0-http--link
                                name:  maryland imap
                                description:  Source Citation URL
                                function:  (CI_OnLineFunctionCode) information
                        role:  (CI_RoleCode) publisher
            processStep:  (LI_ProcessStep)
                description:   The vertical values in this data set have been converted to reference North American Vertical Datum of 1988 (NAVD88) (GEOID18) meters, using the GEOID18 grids provided by the National Geodetic Survey. Any datum and projection transformations were then done with the Office for Coastal Management 'datum_shift' program. Compression to an LAZ file was done with the LAStools 'laszip' program and can be unzipped with the same free program (laszip.org) Processing notes:
                dateTime:
                  DateTime:  2023-07-01T08:43:35
                processor:  (CI_ResponsibleParty)
                    individualName:  NOAA Office for Coastal Management
                    contactInfo:  (CI_Contact)
                        address:  (CI_Address)
                            electronicMailAddress:  coastal.info@noaa.gov
                    role:  (CI_RoleCode) processor