71943 Saipan2019_Lidar_Waveform_Metrics m10031 Data Set Published / External 37139 Biogeography Project Completed 2022-01-21 2024-01-16 This data package contains bathymetric light detection and ranging (lidar) Chiroptera-4X .LAS 1.4 files with waveform metrics (as extra bytes) for 0 to 50 meter depths around the island of Saipan, Commonwealth of the Northern Mariana Islands (CNMI). Bathymetric lidar waveforms depict the amount of laser light returned from the seafloor recorded during each laser pulse. Typically, only the leading edge of the seafloor return is used to calculate bottom depth. However, the shape of the seafloor return also contains novel information about the physical structure and biological cover on the seafloor (Collin et al. 2011, Wilson et al. 2019). To extract this information, the National Oceanic and Atmospheric Administration (NOAA) National Centers for Coastal Ocean Science (NCCOS) partnered with Oregon State University (OSU), NOAA Office for Coastal Management (OCM), Woolpert and Hexagon Leica to develop software to export, process, normalize and rasterize 16 LWFM describing the shape of the seafloor return (Jung et al. In Review; Collin et al. 2011; Parrish et al. 2014; Kashani et al. 2015; Kogut et al. 2022). The resulting LWFM rasters were used to predict the distribution of key coral reef taxa and habitats west of Saipan (Costa et al. 2024). This effort marks one of the few studies that have used LWFM to predict tropical coral reef habitats to date. These processing workflows and associated software will also make LWFM creation easier and more routine for future Chiroptera-4X lidar collections by NOAA and its partners. This project was funded by NOAA's Coral Reef Conservation Program (CRCP), and leverages significant investments made by NOAA NCCOS, NOAA National Geodetic Survey, NOAA Office for Coastal Management, and the U.S. Geological Survey in the region. The purpose of this effort was to develop standardized processes and software to extract, normalize and rasterize bathymetric lidar waveform metrics (LWFM) from the Chiroptera-4X .las files with extra bytes. LWFM have shown promise to enhance NOAA's ability to predict and map the location of benthic habitats (Collin et al. 2011), including coral reefs (Wilson et al. 2019). The study site for this research was 0 to 50 meter depths around the island of Saipan in the Commonwealth of the Northern Mariana Islands (CNMI). This area was selected because its shallow-water coral reefs include ecologically and economically valuable coral taxa, which have been stressed by multiple typhoons and warm-water bleaching events over the last decade. In response to these disasters, NOAA and USGS contracted Woolpert to acquire Chiroptera-4X topographic-bathymetric lidar data around coastal areas of CNMI, including Saipan (Woolpert 2019; NOAA and USGS 2019). These data were used to understand impacts from these disasters in the region, including the damage done to the surrounding coral reefs. The LWFM were used by NOAA NCCOS to create updated coral reef maps for local resource managers on Saipan (Costa et al. 2024) This project was funded under the Coral Reef Conservation Program (CRCP) Project ID: 31309 Cited Publications: Costa, B., Sweeney E. and J. Kraus. 2024. Characterizing Benthic Habitats West of Saipan, CNMI. NOAA Technical Memorandum NOS NCCOS xxxx. Silver Spring, MD. xxxx pp. Collin, A., Archambault, P., & Long, B. (2011). Predicting species diversity of benthic communities within turbid nearshore using full waveform bathymetric LiDAR and machine learners. PloS one, 6(6), e21265. Jung, J., Parrish, C., Costa, B. and Suhong, Y. (In review). Simultaneous Invariant Normalization of Waveform Features from Bathymetric Lidar, SINWav: A Saipan Case Study. Target Journal: ISPRS International Journal of Remote Sensing. Kashani, A. G., Olsen, M. J., Parrish, C. E., & Wilson, N. (2015). A review of LiDAR radiometric processing: From ad hoc intensity correction to rigorous radiometric calibration. Sensors, 15(11), 28099-28128. Kogut, T., Tomczak, A., Sowik, A., & Oberski, T. (2022). Seabed modelling by means of airborne laser bathymetry data and imbalanced learning for offshore mapping. Sensors, 22(9), 3121. NOAA and USGS. (2019). USGS/NOAA Topobathy Lidar DEM: CNMI (Aguijan, Rota, Saipan, Tinian). Online: https://chs.coast.noaa.gov/htdata/raster5/elevation/CNMI_Topobathy_DEM_2019_9474/ (Accessed 15 November 2023). Parrish, C. E., Rogers, J. N., & Calder, B. R. (2014). Assessment of waveform features for lidar uncertainty modeling in a coastal salt marsh environment. IEEE Geoscience and Remote Sensing Letters, 11(2), 569-573. Wilson, N., Parrish, C. E., Battista, T., Wright, C. W., Costa, B., Slocum, R. K., ... & Tyler, M. T. (2019). Mapping seafloor relative reflectance and assessing coral reef morphology with EAARL-B topobathymetric Lidar waveforms. Estuaries and Coasts, 1-15. Woolpert. (2019). Lidar Mapping Report: Project ID 17502, Work Unit 219835. NOAA CONTRACT NUMBER: EA-133C-16-CQ-0046 and USGS CONTRACT NUMBER: G16PC00022. Online: https://rockyweb.usgs.gov/vdelivery/Datasets/Staged/Elevation/metadata/PI_CNMI_2019_D19/PI_CNMI_hydroflattened_ellipsoid_2019/reports/PI_CNMI_2019_D19_Lidar_Mapping_Report_Hydroflattened_Ellipsoid_WU219835.pdf (Accessed 12 JAN 2024). Theme Global Change Master Directory (GCMD) Science Keywords EARTH SCIENCE > OCEANS > BATHYMETRY/SEAFLOOR TOPOGRAPHY > BATHYMETRY Theme Global Change Master Directory (GCMD) Science Keywords EARTH SCIENCE > OCEANS > COASTAL PROCESSES > CORAL REEFS Theme Global Change Master Directory (GCMD) Science Keywords EARTH SCIENCE > SPECTRAL/ENGINEERING > LIDAR Theme Global Change Master Directory (GCMD) Science Keywords EARTH SCIENCE > SPECTRAL/ENGINEERING > LIDAR > LIDAR WAVEFORM Theme ISO 19115 Topic Category geoscientificInformation Theme ISO 19115 Topic Category oceans Spatial Global Change Master Directory (GCMD) Location Keywords CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA Spatial Global Change Master Directory (GCMD) Location Keywords OCEAN > PACIFIC OCEAN > WESTERN PACIFIC OCEAN > MICRONESIA > NORTHERN MARIANA ISLANDS Spatial Global Change Master Directory (GCMD) Location Keywords VERTICAL LOCATION > SEA FLOOR Stratum Global Change Master Directory (GCMD) Vertical Data Resolution Keywords 1 meter - < 10 meters Instrument Global Change Master Directory (GCMD) Instrument Keywords LIDAR > Light Detection and Ranging Platform Global Change Master Directory (GCMD) Platform Keywords Airplane > Airplane Theme CoRIS Discovery Thesaurus Geographic Information > Backscatter Theme CoRIS Discovery Thesaurus Geographic Information > Bathymetry Theme CoRIS Discovery Thesaurus Geographic Information > LiDAR Theme CoRIS Discovery Thesaurus Geographic Information > Marine Management Areas Theme CoRIS Discovery Thesaurus Map Images > Backscatter Theme CoRIS Discovery Thesaurus Map Images > Bathymetry Theme CoRIS Discovery Thesaurus Numeric Data Sets > Backscatter Theme CoRIS Discovery Thesaurus Numeric Data Sets > Bathymetry Theme CoRIS Discovery Thesaurus Numeric Data Sets > Benthic Theme CoRIS Place Ocean/Seas Keywords OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Saipan Island > Chalan Kanoa (15N145E0012) Theme CoRIS Theme Thesaurus EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > GIS Theme CoRIS Theme Thesaurus EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Mapping > Habitat Mapping Theme CoRIS Theme Thesaurus EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Backscatter Theme CoRIS Theme Thesaurus EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Bathymetry Theme CoRIS Theme Thesaurus EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Rugosity Theme CoRIS Theme Thesaurus EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Slope Theme CoRIS Theme Thesaurus EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography >Water Depth Theme CoRIS Theme Thesaurus EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs Theme CoRIS Theme Thesaurus EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs > Coral Reef Ecology > Habitats Theme NCCOS Discovery Keywords NCCOS Research Data Type > Derived Data Product Theme NCCOS Discovery Keywords NCCOS Research Data Type > Field Observation Theme NCCOS Discovery Keywords NCCOS Research Data Type > Geospatial Theme NCCOS Discovery Keywords NCCOS Research Priority > Marine Spatial Ecology Theme NCCOS Discovery Keywords NCCOS Research Topic > Habitat Mapping Theme NODC Data Types HABITAT - BENTHIC Theme Project NOAA Coral Reef Conservation Program Spatial CoRIS Place Country/Territory Keywords COUNTRY/TERRITORY > Northern Mariana Islands > Saipan > Chalan Kanoa (15N145E0012) Spatial CoRIS Place Ocean/Seas Keywords OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Saipan Island > Saipan Island (15N145E0002) Spatial CoRIS Place Thesaurus COUNTRY/TERRITORY > Northern Mariana Islands > Saipan > Saipan Island (15N145E0002) Spatial NCCOS Discovery Keywords NCCOS Research Location > Region > International Spatial NCCOS Discovery Keywords NCCOS Research Location > Region > Pacific Ocean Spatial NCCOS Discovery Keywords NCCOS Research Location > U.S. States and Territories > Mariana Islands > Saipan Stratum Global Change Master Directory (GCMD) Stratum Keywords VERTICAL LOCATION > SEA FLOOR Instrument Hawkeye-4X topo-bathymetric lidar Platform Reims F406 - ZK-XLF National Centers for Coastal Ocean Science Silver Spring MD Data Set Elevation As Needed remote-sensing image Lidar acquisition was funded by NOAA Office for Coastal Management, NOAA National Geodetic Survey, and the U.S. Geological Survey in the region. Lidar was collected by Woolpert Inc. The development of lidar waveform metrics was funded by the NOAA Coral Reef Conservation Program (CRCP) Project ID: 31309 with in-kind contributions from NOAA NCCOS. 71973 Published / External Other Yes Class table describing the class numbers used in the lidar data file. Each point in the lidar file has a class associated. 1 20 - Unclassified Point class number No No Active Unclassified points in or over water 2 22 - Raw Seabed from Lidar Survey Studio Point class number No No Active Points classified by Lidar Survey Studio as seabed that were deemed by the hydrographer to not certain to be seabed. Possibly considered as noise points. 3 24 - High criteria Turbid Water Extraction Point class number No No Active Data classified as possible seabed using the high criteria for the turbid water extraction algorithm. 4 25 - Low criteria Turbid Water Extraction Point class number No No Active Points classified as possible seabed using the low criteria for the turbid water extraction algorithm. 5 26 - Submerged Object Point class number No No Active Points classified as submerged object 6 27 - Bathy low noise Point class number No No Active Bathymetric points considered noise based on the peak shape. 7 29 - Water surface Point class number No No Active Water surface points 8 30 - Derived water surface Point class number No No Active Water surface location derived from surrounding information 9 31 - Bathy laser on land Point class number No No Active Returns from the bathymetric laser on land 10 40 - Bathymetric point Point class number No No Active Returns considered to be seabed. 71974 Published / External Other Yes List of the extra bytes available. Extra bytes are fields beyond the defined LAS record types and are referenced in the LAS 1.4 format specification. 1 Amplitude extra bytes No No Active Maximal peak of the Gaussian curve (Kogut et al., 2022; Parrish et al., 2014) 2 Width extra bytes No No Active Width of a Gaussian curve measured between those points on the y-axis, which are half the maximal peak (Kogut et al., 2022; Parrish et al., 2014) 3 pa_r extra bytes No No Active Aspect ratio (width/amplitude) (Parrish et al., 2014) 4 auc extra bytes No No Active Integration of the tabulated waveform on the closed benthic interval (Collin et al., 2011; Parrish et al., 2014) 5 auc_r extra bytes No No Active AUC right/left ratio (Parrish et al., 2014) 6 slope extra bytes No No Active Slope trailing edge [du/sample] (Parrish et al., 2014) 7 slope_r extra bytes No No Active Trailing/leading slope ratio (Parrish et al., 2014) 8 sigma extra bytes No No Active Standard deviation of the probability distribution of the benthic waveform intensity (Collin et al., 2011; Parrish et al., 2014) 9 mean extra bytes No No Active Mean of the benthic waveform intensity (Collin et al., 2011; Parrish et al., 2014) 10 median extra bytes No No Active Median of the benthic waveform intensity (Collin et al., 2011; Parrish et al., 2014) 11 mode extra bytes No No Active Mode of the benthic waveform intensity (Parrish et al., 2014) 12 skewness extra bytes No No Active Asymmetry of the probability distribution of the benthic waveform intensity (Collin et al., 2011; Parrish et al., 2014) 13 kurtosis extra bytes No No Active Flattening of the probability distribution of the benthic waveform intensity (Collin et al., 2011; Parrish et al., 2014) 14 pearson1 extra bytes No No Active Pearson's 1 skewness coefficient (Parrish et al., 2014) 15 pearson2 extra bytes No No Active Pearson's 2 skewness coefficient (Parrish et al., 2014) Author 2019 2019 Person Parrish, Christopher christopher.parrish@oregonstate.edu Oregon State University (OSU); School of Civil and Construction Engineering Corvallis OR 97331 USA Author 2019 2019 Person Costa, Bryan bryan.costa@noaa.gov Author 2019 2019 Person Jung, Jaehoon jhjung@gnu.ac.kr Gyeongsang National University, Department of Urban Engineering Jinju-si, Gyeongsangnam-do - NA South Korea Collaborator 2019 2019 Organization Hexagon Leica Geosystems https://leica-geosystems.com/ Website Leica geosystems homepage Online Resource Collaborator 2019 Organization Office for Coastal Management OCM https://ror.org/05v14bq57 2234 South Hobson Avenue Charleston SC 29405-2413 https://www.coast.noaa.gov/ Collaborator 2019 2019 Organization Woolpert, Inc. 800-414-1045 https://woolpert.com/ Woolpert Website Main page for Woolpert, Inc. Online Resource Data Steward 2024 Organization NOAA Office for Coastal Management NOAA/OCM coastal.info@noaa.gov 2234 South Hobson Ave Charleston SC 29405-2413 (843) 740-1202 https://coast.noaa.gov NOAA Office for Coastal Management Home Page Online Resource Distributor 2024 Organization NOAA Office for Coastal Management NOAA/OCM coastal.info@noaa.gov 2234 South Hobson Ave Charleston SC 29405-2413 (843) 740-1202 https://coast.noaa.gov NOAA Office for Coastal Management Home Page Online Resource Metadata Contact 2024 Position NCCOS Scientific Data Coordinator NCCOS.data@noaa.gov Point of Contact 2024 Position NCCOS Scientific Data Coordinator NCCOS.data@noaa.gov Point of Contact 2019 Person Costa, Bryan bryan.costa@noaa.gov Principal Investigator 2019 2019 Person Costa, Bryan bryan.costa@noaa.gov Principal Investigator 2019 2019 Person Jung, Jaehoon jhjung@gnu.ac.kr Gyeongsang National University, Department of Urban Engineering Jinju-si, Gyeongsangnam-do - NA South Korea Principal Investigator 2019 2019 Person Parrish, Christopher christopher.parrish@oregonstate.edu Oregon State University (OSU); School of Civil and Construction Engineering Corvallis OR 97331 USA Ground Condition 145.605473 145.837466 15.294146 15.085512 Range 2019-07-11 2019-08-21 Time of data collection. .63 Meter The average point spacing is 0.63 meters. It is spatially variable with an estimated minimum of 0.09 meters and an estimated maximum of 2.23 meters. This includes all points, not ground points only. Yes Yes 739324271 Geographic 3D EPSG:6321 NAD83(PA11) NAD83 (National Spatial Reference System PA11) 6378137 298.257222101 1 Geodetic Lattitude Lat degree north 2 Geodetic Longitude Lon degree east 3 Elipsoidal height h metre up Unclassified 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 dataset is dynamic and may change with time. Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners. Cite As: OCM Partners, [Date of Access]: 2019 - 2020 USGS/NOAA Topobathy Lidar DEM: CNMI (Aguijan, Rota, Saipan, Tinian) [Data Date Range], https://www.fisheries.noaa.gov/inport/item/66821.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 dataset is dynamic and may change with time. Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners. None None https://coast.noaa.gov/dataviewer/#/lidar/search/where:id=10031/details/10031 2024 Organization NOAA Office for Coastal Management Custom download app allowing subsetting, projection change, and generation of derived products. Input Data File Specification: LAS 1.4 Output File Compression: Zip Not Applicable Zip https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/10031/index.html 2024 Organization NOAA Office for Coastal Management Bulk Download Bulk download of data files in vertical orthometric datum, geographic coordinates. LAS/LAZ - LASer Uncompressed https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/10031/supplemental/2019_Saipan_extent_m10031.kmz This graphic displays the footprint for this lidar data set. Browse Graphic KML This graphic displays the footprint for this lidar data set. https://chs.coast.noaa.gov/htdata/raster5/elevation/CNMI_Topobathy_DEM_2019_9474/ USGS/NOAA Topobathy Lidar DEM: CNMI (Aguijan, Rota, Saipan, Tinian) Online Resource NOAA and USGS. (2019). USGS/NOAA Topobathy Lidar DEM: CNMI (Aguijan, Rota, Saipan, Tinian). Online: https://chs.coast.noaa.gov/htdata/raster5/elevation/CNMI_Topobathy_DEM_2019_9474/ (Accessed 15 November 2023). https://doi.org/10.1007/s12237-019-00652-9 https://doi.org/10.1007/s12237-019-00652-9 Online Resource Journal article Wilson, N., Parrish, C. E., Battista, T., Wright, C. W., Costa, B., Slocum, R. K., ... & Tyler, M. T. (2019). Mapping seafloor relative reflectance and assessing coral reef morphology with EAARL-B topobathymetric Lidar waveforms. Estuaries and Coasts, 1-15. https://doi.org/10.1007/s12237-019-00652-9 https://doi.org/10.1109/LGRS.2013.2280182 https://doi.org/10.1109/LGRS.2013.2280182 Online Resource Journal article Parrish, C. E., Rogers, J. N., & Calder, B. R. (2014). Assessment of waveform features for lidar uncertainty modeling in a coastal salt marsh environment. IEEE Geoscience and Remote Sensing Letters, 11(2), 569573. https://doi.org/10.1109/LGRS.2013.2280182 https://doi.org/10.1371/journal.pone.0021265 https://doi.org/10.1371/journal.pone.0021265 Online Resource Journal article Collin, A., Archambault, P., & Long, B. (2011). Predicting species diversity of benthic communities within turbid nearshore using full waveform bathymetric LiDAR and machine learners. PloS one, 6(6), e21265. https://doi.org/10.1371/journal.pone.0021265 https://doi.org/10.3390/s151128099 https://doi.org/10.3390/s151128099 Online Resource Journal article Kashani, A. G., Olsen, M. J., Parrish, C. E., & Wilson, N. (2015). A review of LiDAR radiometric processing: From ad hoc intensity correction to rigorous radiometric calibration. Sensors, 15(11), 28099-28128. https://doi.org/10.3390/s151128099 https://doi.org/10.3390/s22093121 https://doi.org/10.3390/s22093121 Online Resource Journal article Kogut, T., Tomczak, A., Stowik, A., & Oberski, T. (2022). Seabed modelling by means of airborne laser bathymetry data and imbalanced learning for offshore mapping. Sensors, 22(9), 3121. https://doi.org/10.3390/s22093121 https://prd-tnm.s3.amazonaws.com/StagedProducts/Elevation/metadata/PI_CNMI_2019_D19/PI_CNMI_hydroflattened_ellipsoid_2019/reports/PI_CNMI_2019_D19_Lidar_Mapping_Report_Hydroflattened_Ellipsoid_WU219835.pdf Lidar Mapping Report: Project ID 17502 Online Resource PDF Woolpert. (2019). Lidar Mapping Report: Project ID 17502, Work Unit 219835. NOAA CONTRACT NUMBER: EA-133C-16-CQ-0046 and USGS CONTRACT NUMBER: G16PC00022. This report describes the collection of the dataset used as input for this dataset. Not all parts are applicable. 2024-01-23 Data metadata record was created nccos.data@noaa.gov 2024-01-24 Waters, Kirk The return number field appears to be zero for all points, which is not a legitimate value. The extra bytes fields are lacking descriptions and documentation of the fields has not been provided. The classification scheme does not conform to LAS 1.4 specifications. The process for creating the extra bytes waveform metrics has not been documented. Collected using a Leica Hawkeye 4X sensor. Processed in Leica's survey studio, edited in TerraScan and LP360. Other software: QT Modeler, ArcMap, LASTools, proprietary software. Data collected under this Task Order shall meet the National Standard for Spatial Database Accuracy (NSSDA) accuracy standards. The NSSDA standards specify that vertical accuracy be reported at the 95% confidence level for data tested by an independent source of higher accuracy. Non-Vegetated Vertical Accuracy (NVA) of the Lidar Point Cloud data shall be calculated against TINs derived from the final calibrated and controlled swath data. The required accuracy (ACCZ) is: 19.6 cm at a 95% confidence level, derived according to NSSDA, i.e., based on RMSEz of 10 cm in the "open terrain" and/or "Urban" land cover categories. Note, the above statement applies primarily to the topographic portion of the full data set. The vertical accuracy of the bathymetric data was not tested and is expected to have increasing uncertainty with increasing depth. Completeness Commission: The data is programmatically and visually inspected for completeness. | All formatted data cover the entire area specified for this project and are validated using a combination of commercial lidar processing software, GIS software, and proprietary programs to ensure proper formatting and loading prior to delivery. This data was collected by Woolpert, Inc. for the USGS and NOAA Office for Coastal Management (OCM). The LiDAR data was collected for Saipan from 11 Jul to 21 Aug 2019. The bathymetry was georeferenced horizontally to the North American Datum 1983 (NAD83), Universal Transverse Mercator, Zone 55 North (UTM 55N, meters) and vertically to the Northern Marianas Vertical Datum of 2003 (NMVD03, meters) coordinate systems. All lidar data for this project were collected to meet National Geospatial Program Lidar Base Specification Version 1.3 QL1 standard, while simultaneously acquiring bathymetric lidar data at National Coastal Mapping Strategy 1.0 QL2b standard. The Root Mean Square Delta z (RMSDz) was 0.033 for Saipan when comparing adjacent flight lines. For more information, please see NOAA and USGS 2019. Waveform metrics were added by Woolpert, Inc., Oregon State University and NOAA National Centers for Coastal Ocean Science (NCCOS). Data were reduced to geographic coordinates on the ellipsoid for ingest in the Digital Coast by NOAA OCM. Woolpert, Inc. Organization Woolpert, Inc. Originator 1 All lidar data were acquired using a HE4X sensor (Figure 4). The HE4X is a latest generation topographic and bathymetric lidar sensor. The system provides denser data than previous traditional bathymetric lidar systems. It is unique in its ability to acquire bathymetric lidar, topographic lidar and 4-band digital camera imagery simultaneously. The HE4X provided up to 500 kHz topographic data and an effective 140 kHz shallow bathymetric data and a 40 kHz deep channel. While not a required deliverable for this survey, 4-band 80 MP digital camera imagery was also collected simultaneously with the sensor's RCD-30 camera and utilized during data editing in some cases. The bathymetric and topographic lasers are independent and do not share an optical chain or receivers, so they are optimized for their specific function. As with any bathymetric lidar, maximum depth penetration is a function of water clarity and seabed reflectivity. The HE4X is designed to penetrate to 3 times the secchi depth. This is also represented as Dmax = 4/K, where K is the diffuse attenuation coefficient, and assuming K is between 0.1 and 0.3, a normal sea state and 15% seabed reflectance. Both the topographic and bathymetric sub-systems use a palmer scanner to produce an elliptical scan pattern of laser points with a degree of incidence ranging from +/-14 degrees (front and back) to +/-20 degrees (sides), providing a 40 degree field of view. This has the benefit of providing multiple look angles on a single pass and helps to eliminate shadowing effects. This can be of particular use in urban areas, where all sides of a building are illuminated, or for bathymetric features such as the sides of narrow water channels, or features on the seafloor such as smaller objects and wrecks. It also assists with penetration in the surf zone where the back scan passes the same ground location a couple of seconds after the front scan, allowing the areas of whitewater to shift. 2 Position and orientation data were acquired in the aircraft using a NovAtel SPAN with LCI-100C IMU. All data were post-processed using NovAtel Inertial Explorer software to provide a tightly coupled position and orientation solution. A single base station was used to control trajectory processing providing final trajectories for Saipan and Tinian on NAD83 (MA11), Epoch 2010, located in the Saipan airport. This base station was replaced for each of the three separate collects of the project (Table 11). SPN1, SPN2 and SPN3 were occupied with a Trimble GNSS receiver by Woolpert. Due to the distance of Rota, Aguijan, Farallon de Medinilla, and Pagan from the single base station on Saipan and their remoteness a precise point positioning (PPP) solution was used for them on ITRF2014. To establish a reliable coordinate for SPN1 data were uploaded to the National Geodetic Service (NGS) Online Positioning User Service (OPUS), and for SPN2 and SPN3 Trimble CenterPoint RTX Post-Processing service was used. The average OPUS or RTX coordinate from multiple days of observations was used to process the final trajectories. 3 Initial data coverage analysis and quality checks to ensure there were no potential system issues were carried out in the field prior to demobilization of the sensor. Final processing was conducted in Woolpert's offices. In general data were initially processed in Leica's Lidar Survey Studio (LSS) using final processed trajectory information. LAS files from LSS were then imported to a Terrascan project where spatial algorithms were used to remove noise and classify bare earth/ground. Manual review was conducted in both Terrascan and LP360 prior to product creation. 4 Lidar processing was conducted using the Leica Lidar Survey Studio (LSS) software. Calibration information, along with processed trajectory information were combined with the raw laser data to create an accurately georeferenced lidar point cloud for the entire survey in LAS v1.4 format. All points from the topographic and bathymetric laser include 16-bit intensity values. During this LSS processing stage, an automatic land/water discrimination is made for the bathymetric waveforms. This allows the bathymetric (green) pulses over water to be automatically refracted for the pulse hitting the water surface and travelling through the water column, producing the correct depth. Another advantage of the automatic land/water discrimination is that it permits calculation of an accurate water surface over smaller areas, allowing simple bathymetric processing of smaller, narrower streams and drainage channels. Sloping water surfaces are also handled correctly. Prior to processing, the hydrographer can adjust waveform sensitivity settings dependent on the environment encountered and enter a value for the refraction index to be used for bathymetry. The index of refraction is an indication of the water type. Values used for sensitivity settings and the index of refraction are included in the LSS processing settings files. A value of 1.34206 was used for the index of refraction, indicating saltwater. In the field, default waveform sensitivity settings were used for processing. In order to determine the optimal waveform sensitivity settings for final processing, sample areas were selected and processed with multiple different settings, to iteratively converge on the best possible settings. This is done by reviewing the processed point cloud and waveforms within sample areas. Settings affect which waveform peaks are classified as valid seabed, and which peaks are classified as noise. Optimal settings strike a balance between the amount of valid data that is classified as seabed bottom, and the amount of noise that is incorrectly classified due to peaks in the waveforms. Ideally all valid data is selected, while only a small amount of noise remains to be edited out. Once optimal threshold settings were chosen, these were used for the entire project. It is important to note that all digitized waveform peaks are available to be reviewed by the hydrographer; both valid seabed bottom and peaks classed as noise. This allows the hydrographer to review data during TerraScan and LP360 editing for valid data such as objects that may have been misclassified as noise. LSS processing produced LAS files in 1.4 format. Additional QC steps were performed prior to import to TerraScan. Firstly, the derived water surface was reviewed to ensure a water surface was correctly calculated for all bathymetry channels. No significant issues were apparent. Spot checks were also made on the data to ensure the front and back of the scans remained in alignment and no calibration or system issues were apparent prior to further data editing in TerraScan. LSS stores data in multiple LAS files for a single flight line. Each file corresponds to a single .dat file from the raw airborne data. Woolpert merged these multiple files into a single file per flight line and moved data into a standard class definition in preparation for data editing using Woolpert's proprietary scripts within SAFE's FME software. Data produced by LSS for flights over Saipan and Tinian were processed on the NAD83 (MA11) Epoch 2010 datum in UTM 55N Zone with units in meters, and elevations on the ellipsoid also in meters. Data produced for Aguijan and Rota were processed on the ITRF2014 datum in UTM 55N Zone with units in meters, with elevations on the ellipsoid also in meters. 5 After data were processed in LSS and the data integrity reviewed, Aguijan, and Rota were transformed from the ITRF2014 ellipsoid to the NAD83 (MA11) Epoch 2010 ellipsoid using VDatum. With the entire project now on the correct ellipsoid, data were organized into tiles within a TerraScan project. The tile layout is the same as that provided with the project deliverables. Data classification and spatial algorithms were applied in Terrasolid's TerraScan software. Customized spatial algorithms, such as isolated points and low point filters, were run to remove gross fliers in the topographic and bathymetric data. A grounding algorithm was also run on the topographic data to distinguish between points representing the bare earth, and other valid topo lidar points representing features such as vegetation, buildings, and so forth. Algorithms were run on the entire dataset. Data were reviewed manually to reclassify any valid bathy points incorrectly identified by the automated routines in LSS as invalid, and vice versa. In addition, any topo points over the water were reclassified to correct the ground representation. Manual editing was conducted both in TerraScan and LP360. Steps for manual editing included: - Re-class any topo unclassified laser data and bathy seabed data from the water surface to a water surface class - Review bathymetry in cross section. - Re-class suitable data to Seabed (Class 40). - Re-class any noise in the bathy ground class to bathy noise (Class 45). - Review bathymetry using imagery and nautical charts and re-class obvious man-made objects to Submerged Object (Class 43). Once editing was completed in TerraScan the data were vertically transformed to the NMVD03 datum using GEOID12B. 7 Data were received by NOAA OCM from NOAA NCCOS in NAD83(MA11) UTM 55N coordinates with the vertical in NMVD03/Geoid12b. Waveform metrics had been added as extra bytes, but no documentation of the process was provided. The projection and geoid model were removed to produce geographic coordinates on the ellipsoid (EPSG:6321) for incorporation into the NOAA Digital Coast to allow custom processing. 2024-01-24T00:00:00 Organization Office for Coastal Management OCM https://ror.org/05v14bq57 2234 South Hobson Avenue Charleston SC 29405-2413 https://www.coast.noaa.gov/ 71973 Entity 71974 Entity 66790 Data Set Larger Work Citation Original collection of data in CNMI. This was the input data for the waveform processing. gov.noaa.nmfs.inport:71943 Lauren Jackson 2024-01-23T22:15:52 SysAdmin InPortAdmin 2026-08-19T18:34:11 2024-01-24 National Centers for Coastal Ocean Science NCCOS 1002 Public No No 2024-01-24 3 Years 2027-01-24