OPR-T381-RA-22 Mariana Islands Western Pacific Ocean NOAA Ship Rainier (S221) H13580 10 Farallon de Pajaros Island Northern Mariana Islands United States 10000 2022 Héctor L. Casanova, CAPT/NOAA Navigable Area 2022-01-07 2022-06-23 2022-06-24 Multibeam Echo Sounder Multibeam Echo Sounder Backscatter meters UTC Pacific Hydrographic Branch Any revisions to the Descriptive Report (DR) applied during office processing are shown in red italic text. The DR is maintained as a field unit product, therefore all information and recommendations within this report are considered preliminary unless otherwise noted. The final disposition of survey data is represented in the NOAA nautical chart products. All pertinent records for this survey are archived at the National Centers for Environmental Information (NCEI) and can be retrieved via https://www.ncei.noaa.gov/. Products created during office processing were generated in NAD83(MA11) UTM 55N. All references to other horizontal or vertical datums in this report are applicable to the processed hydrographic data provided by the field unit. CC0-1.0 (NOAA Field Units) CC0-1.0 https://creativecommons.org/publicdomain/zero/1.0/ https://creativecommons.org/publicdomain/zero/1.0/legalcode These data were produced by NOAA and are in the public domain within the United States. NOAA waives any potential copyright and related rights in these data worldwide through the Creative Commons Zero 1.0 Universal Public Domain Dedication (CC0). NOAA The survey area is referred to as H13580, "Farallon de Pajaros Island" (Sheet 10) in the Project Instructions. The assigned survey area encompassed an estimated 270 square nautical miles and is located at the northern most end of the Mariana Island chain. 20.69333 145.734184 20.361463 145.419843 Assigned H13580 survey area. SupportFiles\H13580_Assigned_Sheet_Limits.jpg The originally assigned survey limits extended into areas with depths greater than RAINIER could efficiently acquire quality multibeam data. Therefore we requested, and the Operations Branch approved, that we survey to the 1,500 meter depth contour and not beyond. See supplemental correspondence for more information. The figure below displays the multibeam data acquired on Farallon de Pajaros Island with a color scale that distinguishes the 1500 meter contour in the color pink. Acquired H13580 survey coverage. The pink colored surface indicates 1500 meter depths or greater. (Chart 81004) SupportFiles\H13580_1500m_Pink.png The ecosystem surrounding the Commonwealth of the Northern Mariana Islands (CNMI) is experiencing stress imposed by climate change and other environmental factors. This survey is part of extensive hydrographic project intended to map the bathymetry and habitat around the CNMI in support of nautical charting and habitat mapping. With the collaboration and partnership of the National Centers for Coastal and Ocean Science (NCCOS), the NOAA Coral Reef Conservation Program (CRCP), and the National Marine Fisheries Service (NMFS), this survey will also study the health of coral reef systems, ocean chemistry, and fisheries habitat. This team has developed a strategy to map the waters from nearshore to depths greater than 1000 meters. Within these waters, the ship's crew and visiting scientists will map bathymetry and backscatter and characterize habitat, while concurrently performing coral reef assessment dives and collecting other oceanographic observations. Data collected during this mission are pivotal to long-term biological and oceanographic monitoring of coral reef ecosystems around the CNMI. Data from this survey will add to information collected during prior monitoring and mapping projects. Oceanographic and ecological time series data will allow scientists to evaluate potential changes in environmental conditions and coral reef health in the Mariana Archipelago. This will enable federal and state resource managers to more effectively conserve the coral reef ecosystems of the CNMI, and to manage ecosystems services. Data collected during this survey also support monitoring components of the CRCP Coral Reef Ecosystem Integrated Observing System. The entire survey is adequate to supersede previous data. Pydro QC Tools 2 Grid QA was used to analyze H13580 multibeam echosounder (MBES) data density. The submitted H13580 Variable Resolution (VR) surface met HSSD density requirements in only 93% of grid nodes as shown in the histogram plot below and not the HSSD required 95% or higher. This outcome was a result of the 32 meter resolution grid being used for depths exceeding 640 meters. The result was also due to the large area of deeper waters exceeding 1500 meters in depth and steep slopes surveyed in this sheet. Pydro QC Tools 2 Grid QA was also used to analyze H13580 MBES Resolution Requirements. As seen in the figure below, sheet H13580 shows a 97% pass for resolution requirements, meeting the HSSD requirement. Compared to other sheets in project OPR-T381-RA-22, the resolution requirements for sheet H13580 were higher due to the use of the 32 meter resolution grid for depths exceeding 640 meters in the finalized surface, matching HSRR specifications. Pydro derived histogram plot showing 93% of nodes meeting HSSD density compliance in H13580 finalized variable-resolution MBES data. SupportFiles\H13580_MB_VR_MLLW_Final.QAv6.density.png Pydro derived plot showing Grid QA results of H13580 full coverage resolution requirements. SupportFiles\H13580_MB_VR_MLLW_Final.QAv6.pct_res.full_cov.png All Waters Complete Coverage (Refer to HSSD Section 5.2.2.3) The entire extent of the assigned sheet limits was not surveyed for H13580. Multibeam Echosounder (MBES) coverage was acquired to the inshore limit of hydrography, the Navigable Area Limit Line (NALL), within a majority of the assigned sheet limits. The NALL is defined as the most seaward of the following: the line defined by the distance seaward from the observed MHW line which is equivalent to the 0.8 millimeters at chart scale (the assigned sheet limits closely reflect this) or the inshore limit of safe navigation. For H13580, per the Project Instructions, the inshore limit of safe navigation was defined as 10 meters water depth or the inshore limit of the PRF polygon. Additionally, per correspondence with the Project Manager, it was determined that NOAA ship RAINIER would only acquire data to 1500 meters. See supplemental correspondence and the Project Instructions provided with this report for more information. The below figure illustrates the areas in which MBES data were collected. H13580 MBES coverage and assigned survey limits for Farallon de Pajeros Island. (Chart 81004) SupportFiles\H13580_Survey_Coverage.PNG S221 0.0 139.75 0.0 0.0 0.0 0.0 0.0 28.93 0.0 2803 0.0 25.93 0.0 0.0 0.0 0.0 0.0 1.69 0.0 0.0 165.68 0.0 0.0 0.0 0.0 0.0 30.62 0.0 18.4 0 0 1 0 123.61 2022-06-23 2022-06-24 Refer to the Data Acquisition and Processing Report (DAPR) for a complete description of data acquisition and processing systems, survey vessels, quality control procedures and data processing methods. Additional information to supplement sounding and survey data, and any deviations from the DAPR are discussed in the following sections. S221 70.4 4.7 2803 8.8 1.1 NOAA Ship RAINIER with one survey launch, dive boat, and fast rescue boat in view from left to right. SupportFiles\Rainier_in_Honolulu_crop.jpg All data for H13580 were acquired by NOAA Ship RAINIER and survey launch 2803. Survey launch 2803 verified shoreline features. The vessels acquired depth soundings, backscatter imagery, and sound speed profiles. MBES Kongsberg Maritime EM 2040 MBES Kongsberg Maritime EM 710 Positioning and Attitude System Applanix POS MV 320 v5 Conductivity, Temperature, and Depth Sensor Sea-Bird Scientific SBE 19plus Sound Speed System ODIM Brooke Ocean MVP200 Sound Speed System Teledyne RESON SVP 70 NOAA Ship RAINIER and survey launch 2803 acquired 30.6 nautical miles (18.4% of mainscheme) of MBES crosslines across all depth ranges, water masses and boat days that were operationally practical, in order to evaluate the internal consistency of H13580 sonar data. We performed crossline analysis using the Compare Grids function within Pydro Explorer on Caris variable-resolution surfaces of H13580 mainscheme only and crossline only data. Results showed that 97% of grid nodes met allowable uncertainties as shown in the Pydro generated plots below. H13580 crossline surface overlaid on mainscheme tracklines. SupportFiles\H13580_XLs.jpg Pydro derived plot showing node percentage pass value of H13580 mainscheme to crossline data. SupportFiles\H13580_VR_MS_Only-H13580_VR_XL_Only_fracAllowErr_Freq.png Pydro derived plot showing absolute difference statistics of H13580 mainscheme to crossline data. SupportFiles\H13580_VR_MS_Only-H13580_VR_XL_Only_depth_delta.png ERS via VDATUM 0.0 0.11 S221 1 0.05 2803 3 0.05 Total Propagated Uncertainty (TPU) values for survey H13580 were derived from a combination of fixed values for equipment and vessel characteristics, as well as from field assigned values for sound speed uncertainties. Tidal uncertainty was provided in metadata for the NOAA vertical datum transformation model used for this survey. In addition to the usual a priori estimates of uncertainty, real-time and post-processed uncertainty sources were also incorporated into the depth estimates of this survey. Real-time uncertainties for position, navigation and vessel motion data from Applanix POS MV were applied during acquisition and initially in post-processing. POSPac SBET and RMS files were subsequently applied in Caris HIPS to supersede POS MV uncertainties associated with GPS height and position. Uncertainty values of the submitted finalized grids were calculated in Caris using "Greater of the Two" of uncertainty and standard deviation (scaled to 95%). Grid QA v6 within Pydro QC Tools was used to analyze H13580 TVU compliance. H13580 met HSSD requirements in 99% percent of grid nodes as shown in the histogram plot below. Pydro derived plot showing TVU compliance of H13580 finalized multi-resolution MBES data. SupportFiles\H13580_MB_VR_MLLW_Final.QAv6.tvu_qc.png Sonar system quality control checks were conducted as detailed in the quality control section of the DAPR. None Exist There were no conditions or deficiencies that affected equipment operational effectiveness. None Exist There were no other factors that affected corrections to soundings. Sixteen sound speed profiles ("casts") were acquired for this survey at discrete locations within the assigned area at least once every four hours, when significant changes to surface sound speed were observed, or when shifting operations to a new area. Sound speed profiles were obtained using the Sea-Bird 19plus SEACAT Profilers on survey launch 2803 and the ODIM Brooke MVP200 on the ship. All sound speed profiles were concatenated into a master file and applied to H13580 MBES data using the "Nearest distance within Time" (4 hours) profile selection method. H13580 sound speed cast locations. SupportFiles\H13580_SV_Casts.jpg All equipment and survey methods were used as detailed in the DAPR. All data reduction procedures conform to those detailed in the DAPR. All sounding systems were calibrated as detailed in the DAPR. Raw backscatter data were acquired as .all files logged during MBES operations and subsequently processed by RAINIER personnel. The .GSF files created during processing and backscatter mosaic data has been delivered with this report. Backscatter processing procedures are described in the DAPR. H13580 multibeam acoustic backscatter overview. (Chart 81004) SupportFiles\H13580_MBAB.jpg CARIS HIPS and SIPS 11.4.6 QPS FMGT 7.10.0 NOAA Profile Version 2022 H13580_MB_VR_MLLW CARIS VR Surface (CUBE) Variable Resolution 4.1 2715.0 NOAA_VR Complete MBES H13580_MB_VR_MLLW_Final CARIS VR Surface (CUBE) Variable Resolution 4.1 2715.0 NOAA_VR Complete MBES Submitted H13580 surfaces were generated using NOAA recommended parameters for depth-based (Ranges) Caris variable-resolution bathymetric grids. The submitted surfaces were generated with a Range/Resolution file, that includes 32 meter grids for depths exceeding 640 meters. The multibeam data were iteratively cleaned of outlying and influential, anomalous soundings using Pydro QC Tools (v3.7.0). Pydro QC Tool's Flier Finder (v9), with default settings, was used to identify sounding "fliers" in the finalized H13580 VR surface. Obvious noise was rejected by the hydrographer in Caris Subset Editor. After data cleaning, the Flier Finder tool was run again and found 339 potential fliers in the Complete Coverage surface. The potential fliers were investigated and determined to be a result of the significant slope in the terrain and the limited data density on both the steep slope and the offshore edge of coverage. Therefore, these fliers have been found to be false positives. The image below depicts an example of edge fliers determined to be false positives. Pydro QC Tool's Holiday Finder (v4), with default settings, was used to find holidays in the finalized H13580 VR surface. Zero holidays were detected in the final Complete Coverage surface. Example of fliers determined to be false positives. SupportFiles\H13580_FlierExample.png Additional information discussing the vertical or horizontal control for this survey can be found in the accompanying DAPR. Mean Lower Low Water ERS via VDATUM OPR_T381-RA-22_GuamCNMI_EC_ERTDM2021_NAD83(MA11)-MLLW OPR_T381-RA-22_GuamCNMI_EC_ERTDM2021_NAD83(MA11)-MHW All submitted H13580 MBES data were vertically referenced to the ellipsoid. VDATUM models included with the Project Instructions were used for referencing H13580 data to MLLW and MHW. North American Datum 1983 (MA11) Projected UTM 55 Precise Positioning-Real time Extended (PP-RTX) processing methods were used in Applanix POSPac MMS (v8.5) software for post-processing horizontal correction of submitted H13580 MBES data. The Wide Area Augmentation System (WAAS) was used for real-time horizontal control during data acquisition. Limited shoreline verification was conducted in accordance with applicable sections of NOAA HSSD and FPM using the Composite Source File (CSF) provided by the Operations Branch. In the field, all assigned unverified charted features that were safe to approach, were addressed as required with S57 attribution and recorded in the H13580 Final Feature File (FFF) to best represent the features at chart scale. This file also includes recommendations to update, retain or delete assigned features. Features that were unsafe to approach were attributed in the FFF as Not Addressed, and the reason stated. US5SP08M 45602 9 2020-09-30 2020-09-30 US2SP01M 931650 19 2021-09-07 2021-09-07 No Danger to Navigation Reports were submitted for this survey. ENC US2SP01M has several areas designated as obstructions that have been covered with MBES data. Three obstructions have been assigned due to discolored water being reported. Two obstructions to the north of Farallon de Pajaros and one obstruction to the southeast of Farallon de Pajaros have been assigned due to the area being "shoaler than range of depth of surrounding depth area." It is recommended that all of these obstructions are removed from the chart due to superseding MBES data as mentioned in the FFF. The figure below shows two obstructions to the north of the Farallon de Pajaros Island with overlaying MBES coverage. H13580 MBES coverage overtop charted obstructions. (Chart 81004) SupportFiles\H13580_MBES_OverObstruction.png No uncharted features exist for this survey. No channels exist for this survey. There are no designated anchorages, precautionary areas, safety fairways, traffic separation schemes, pilot boarding areas, or channel and range lines within the survey limits. No Aids to navigation (ATONs) exist for this survey. No Maritime Boundary Points were assigned for this survey. No bottom samples were required for this survey. No overhead features exist for this survey. No submarine features exist for this survey. No platforms exist for this survey. No ferry routes or terminals exist for this survey. No abnormal seafloor or environmental conditions exist for this survey. No present or planned construction or dredging exist within the survey limits. No new surveys or further investigations are recommended for this area. No new ENC scales are recommended for this area. As Chief of Party, field operations for this hydrographic survey were conducted under my direct supervision, with frequent personal checks of progress and adequacy. I have reviewed the attached survey data and reports. All field sheets, this Descriptive Report, and all accompanying records and data are approved. All records are forwarded for final review and processing to the Processing Branch. The survey data meets or exceeds requirements as set forth in the NOS Hydrographic Surveys Specifications and Deliverables, Field Procedures Manual, Letter Instructions, and all HSD Technical Directives. These data are adequate to supersede charted data in their common areas. This survey is complete and no additional work is required with the exception of deficiencies noted in the Descriptive Report. Héctor L. Casanova, CAPT/NOAA Chief of Party 2022-09-26 Collin H. Walker, LT/NOAA Field Operations Officer 2022-09-26 James B. Jacobson Chief Survey Technician 2022-09-26 Franco R. Pilone Sheet Manager 2022-09-26