| 2016 DOWL Lidar: Chena River Lakes, Alaska | spatialRepresentationInfo|
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| (MI_Metadata) fileIdentifier: gov.noaa.nmfs.inport:52861 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) return to top spatialRepresentationInfo: return to top referenceSystemInfo: return to top 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 return to top referenceSystemInfo: (MD_ReferenceSystem) referenceSystemIdentifier: (RS_Identifier) authority: (CI_Citation) title: North American Vertical Datum of 1988 (NAVD88) (GEOID12B) meters alternateTitle: North American Vertical Datum of 1988 (NAVD88) (GEOID12B) 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) (GEOID12B) 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 return to top identificationInfo: (MD_DataIdentification) citation: (CI_Citation) title: 2016 DOWL Lidar: Chena River Lakes, Alaska alternateTitle: ak2016_chena_m8540_metadata date: (CI_Date) date: (missing) dateType: (CI_DateTypeCode) publication identifier: (MD_Identifier) authority: (CI_Citation) title: NOAA/NMFS/EDM date: (inapplicable) code: Anchor: InPort Catalog ID 52861 citedResponsibleParty: (CI_ResponsibleParty) organisationName: (inapplicable) contactInfo: (CI_Contact) onlineResource: (CI_OnlineResource) linkage: https://www.fisheries.noaa.gov/inport/item/52861 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://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/8540/supplemental/ak2016_chena_m8540_lidar_report.pdf protocol: WWW:LINK-1.0-http--link name: Dataset report description: Link to data set report. 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: This metadata record was created by the NOAA Office for Coastal Management (OCM) because no metadata record was available for the data. Information to create this record was taken from the Quantum Spatial Chena River Lakes LiDAR Technical Data Report. There is a link to this report in the URL section of this metadata record. The data set deliverable parameters provided in the technical report for projection and units, are incorrectly provided in the report for the point data. The report indicates that the data are in Alaska State Plane Zone 3, NAD83 (NSRS2007), US survey feet and in NAVD88 (GEOID06) with vertical units in US survey feet. After examining the data and using the LAStools script lasinfo, the data downloaded from AK DGGS, appear to actually be in UTM Zone 6N, NAD83, meters, and in vertical units of meters. The NOAA Office for Coastal Management (OCM) downloaded this lidar data from the AK DGGS site (https://elevation.alaska.gov/) and processed the data to be available on the Digital Coast Data Access Viewer (DAV). In addition to these lidar point data, the bare earth Digital Elevation Models (DEM) created from the lidar point data are also available. These data are available for custom download at the link provided in the URL section of this metadata record. In early 2016, Quantum Spatial (QSI) was contracted by DOWL, Inc. to collect Light Detection and Ranging (LiDAR) data in the spring of 2016 for the Chena River Lakes site in Alaska. This data set is an LAZ (compressed LAS) format file containing LIDAR point cloud data. purpose: Data were collected to aid DOWL, Inc. in assessing the topographic and geophysical properties of the study area and to support engineering and mapping endeavors. credit: DOWL, Inc. 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) unknown graphicOverview: (MD_BrowseGraphic) fileName: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/8540/supplemental/ak2016_chena_m8540.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 > ALASKA 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: erosion type: (MD_KeywordTypeCode) theme descriptiveKeywords: (MD_Keywords) keyword: 2016 keyword: May type: (MD_KeywordTypeCode) temporal 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]: 2016 DOWL Lidar: Chena River Lakes, Alaska [Data Date Range], https://www.fisheries.noaa.gov/inport/item/52861. 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: 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: 52861 citedResponsibleParty: (CI_ResponsibleParty) organisationName: (inapplicable) contactInfo: (CI_Contact) onlineResource: (CI_OnlineResource) linkage: https://www.fisheries.noaa.gov/inportserve/waf/noaa/nos/ocmp/dmp/pdf/52861.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 language: eng; US topicCategory: (MD_TopicCategoryCode) elevation extent: (EX_Extent) geographicElement: (EX_GeographicBoundingBox) westBoundLongitude: -147.321 eastBoundLongitude: -147.04 southBoundLatitude: 64.7 northBoundLatitude: 64.838 temporalElement: (EX_TemporalExtent) extent: TimeInstant: description: | Currentness: Ground Condition timePosition: 2016-05-01 return to top distributionInfo: (MD_Distribution) 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=8540 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. A new metadata will be produced to reflect your request using this record as a base. function: (CI_OnLineFunctionCode) download transferOptions: (MD_DigitalTransferOptions) onLine: (CI_OnlineResource) linkage: https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/8540/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. Note that the vertical datum (hence elevations) of the files here are different than described in this document. function: (CI_OnLineFunctionCode) download return to top dataQualityInfo: (DQ_DataQuality) scope: (DQ_Scope) level: (MD_ScopeCode) dataset report: (DQ_AbsoluteExternalPositionalAccuracy) nameOfMeasure: Vertical Positional Accuracy evaluationMethodDescription: Absolute accuracy was assessed using Fundamental Vertical Accuracy (FVA) reporting designed to meet guidelines presented in the FGDC National Standard for Spatial Data Accuracy 2. FVA compares known ground quality assurance point data collected on open, bare earth surfaces with level slope (<20 degrees) to the triangulated surface generated by the LiDAR points. FVA is a measure of the accuracy of LiDAR point data in open areas where the LiDAR system has a high probability of measuring the ground surface and is evaluated at the 95% confidence interval (1.96 * RMSE). The mean and standard deviation of divergence of the ground surface model from quality assurance point coordinates are also considered during accuracy assessment. These statistics assume the error for x, y, and z is normally distributed, and therefore the skew and kurtosis of distributions are also considered when evaluating error statistics. For the Chena River Lakes survey, 80 quality assurance points were used for Fundamental Vertical Accuracy (FVA) calculations which resulted in an FVA value of 0.188 feet (0.057 meters) . Vertical accuracy was also assessed using Supplemental Vertical Accuracy (SVA) and Consolidated Vertical Accuracy (CVA) reporting. SVA compares known ground check point data within individual land cover class categories to the triangulated ground surface generated by the ground classified LiDAR points while CVA compares known ground check points within all land cover classes. SVA and CVA are evaluated at the 95th percentile. SVA Brush - 0.452 ft (0.138 m) Gravel - 0.152 ft (0.046 m) Forest - 0.337 ft (0.102 m) CVA - 0.231 ft (0.070 m) result: (missing) report: (DQ_CompletenessCommission) nameOfMeasure: Completeness Report evaluationMethodDescription: Complete result: (missing) lineage: (LI_Lineage) statement: (missing) processStep: (LI_ProcessStep) description: Planning In preparation for data collection, QSI reviewed the project area and developed a specialized flight plan to ensure complete coverage of the Chena River Lakes LiDAR study area at the target point density of ≥12.0 points/m2 (1.11 points/ft2). Acquisition parameters including orientation relative to terrain, flight altitude, pulse rate, scan angle, and ground speed were adapted to optimize flight paths and flight times while meeting all contract specifications. Factors such as satellite constellation availability and weather windows must be considered during the planning stage. Any weather hazards or conditions affecting the flights were continuously monitored due to their potential impact on the daily success of airborne and ground operations. In addition, logistical considerations including private property access and potential air space restrictions were reviewed. processStep: (LI_ProcessStep) description: Acquisition The LiDAR survey was accomplished using a Leica ALS80 system mounted in a Cessna Caravan. Table 3 in the technical report summarizes the settings used to yield an average pulse density of greater than or equal to 12 pulses/m2 over the Chena River Lakes project area. The Leica ALS80 laser system can record unlimited range measurements (returns) per pulse. It is not uncommon for some types of surfaces (e.g., dense vegetation or water) to return fewer pulses to the LiDAR sensor than the laser originally emitted. The discrepancy between first return and overall delivered density will vary depending on terrain, land cover, and the prevalence of water bodies. All discernible laser returns were processed for the output dataset. All areas were surveyed with an opposing flight line side-lap of ≥60% (≥100% overlap) in order to reduce laser shadowing and increase surface laser painting. To accurately solve for laser point position (geographic coordinates x, y and z), the positional coordinates of the airborne sensor and the attitude of the aircraft were recorded continuously throughout the LiDAR data collection mission. Position of the aircraft was measured twice per second (2 Hz) by an onboard differential GPS unit, and aircraft attitude was measured 200 times per second (200 Hz) as pitch, roll and yaw (heading) from an onboard inertial measurement unit (IMU). To allow for post-processing correction and calibration, aircraft and sensor position and attitude data are indexed by GPS time. dateTime: DateTime: 2016-05-01T00:00:00 processStep: (LI_ProcessStep) description: Ground Control Ground control surveys, including monumentation and the collection of ground survey points (GSPs), were conducted by DOWL to support the airborne acquisition. Ground control data were used to geospatially correct the aircraft positional coordinate data and to perform quality assurance checks on final LiDAR data. QSI used static GNSS data provided by DOWL from base stations set up over three monument locations for the Chena River Lakes LiDAR project All survey data were reviewed by QSI staff upon receipt, and monument positions were verified by processing static GNSS data against nearby Continuously Operating Reference Stations (CORS) using the Online Positioning User Service (OPUS1). Ground survey points were collected by DOWL using real time kinematic survey techniques and supplied to QSI for LiDAR calibration. In addition to ground survey points, land cover class control points were collected and provided by DOWL throughout the study area. Individual accuracies were calculated for each land cover type to assess confidence in the LiDAR-derived ground models across land cover classes. processStep: (LI_ProcessStep) description: Lidar Processing Upon completion of data acquisition, QSI processing staff initiated a suite of automated and manual techniques to process the data into the requested deliverables. Processing tasks included GPS control computations, smoothed best estimate trajectory (SBET) calculations, kinematic corrections, calculation of laser point position, sensor and data calibration for optimal relative and absolute accuracy, and LiDAR point classification. Processing methodologies were tailored for the landscape. Resolve kinematic corrections for aircraft position data using kinematic aircraft GPS and static ground GPS data. Develop a smoothed best estimate of trajectory (SBET) file that blends post-processed aircraft position with sensor head position and attitude recorded throughout the survey. Calculate laser point position by associating SBET position to each laser point return time, scan angle, intensity, etc. Create raw laser point cloud data for the entire survey in *.las (ASPRS v. 1.2) format. Convert data to orthometric elevations by applying a geoid06 correction Import raw laser points into manageable blocks to perform manual relative accuracy calibration and filter erroneous points. Classify ground points for individual flight lines. Using ground classified points per each flight line, test the relative accuracy. Perform automated line-to-line calibrations for system attitude parameters (pitch, roll, heading), mirror flex (scale) and GPS/IMU drift. Calculate calibrations on ground classified points from paired flight lines and apply results to all points in a flight line. Use every flight line for relative accuracy calibration. Classify resulting data to ground and other client designated ASPRS classifications. Assess statistical absolute accuracy via direct comparisons of ground classified points to ground control survey data. Generate bare earth models as triangulated surfaces. Generate highest hit models as a surface expression of all classified points. Export all surface models as ESRI GRIDs at a 3.0 foot pixel resolution. Correct intensity values for variability and export intensity images as GeoTIFFs at a 1.5 foot pixel resolution. processStep: (LI_ProcessStep) description: The NOAA Office for Coastal Management (OCM) downloaded 507 laz files from the Alaska Division of Geological and Geophysical Surveys data Portal (https://elevation.alaska.gov/). The files contained elevation and intensity measurements for the 2016 Chena River Lakes data set. The data set deliverable parameters provided in the technical report for projection and units, are incorrectly provided in the report for the point data. The report indicates that the data are in Alaska State Plane Zone 3, NAD83 (NSRS2007), US survey feet and in NAVD88 (GEOID06) with vertical units in US survey feet. After examining the data and using the LAStools script lasinfo, the data downloaded from AK DGGS, appear to actually be in UTM Zone 6N, NAD83, meters, and in vertical units of meters. The data were classified as: 1 - Unclassified, 2 - Ground, 7 - Noise, 9 - Water. The NOAA Office for Coastal Management processed all points to the Digital Coast Data Access Viewer (DAV). OCM performed the following processing on the data for Digital Coast storage and provisioning purposes: 1. The LAStools software scripts lasinfo and lasvalidate were run on the laz files to check for errors. 2. An internal OCM script was run to check the number of points by classification and by flight ID and the gps and intensity ranges. 3. Internal OCM scripts were run on the laz files to convert from UTM Zone 6N, NAD83, meters coordinates to geographic coordinates, to convert from NAVD88 elevations to ellipsoid elevations using the GEOID06 model, to assign the geokeys, to sort the data by gps time and zip the data to database and to http. dateTime: DateTime: 2018-06-11T00:00:00 processor: (CI_ResponsibleParty) organisationName: Office for Coastal Management role: (CI_RoleCode) processor processStep: (LI_ProcessStep) description: The vertical values in this data set have been converted to reference North American Vertical Datum of 1988 (NAVD88) (GEOID12B) meters, using the GEOID12B 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: 2023-07-01T05:18:42 processor: (CI_ResponsibleParty) individualName: NOAA Office for Coastal Management contactInfo: (CI_Contact) address: (CI_Address) electronicMailAddress: coastal.info@noaa.gov role: (CI_RoleCode) processor | |