OPR-S347-FA-18Point Hope & VicinityLisburne Peninsula, AlaskaNOAA Ship FAIRWEATHERH1312348.5 NM Due North of Point HopeAlaskaUnited States200002018Commander Marc Moser, NOAANavigable Area2018-06-072018-07-152018-08-15Multibeam Echo SounderMultibeam Echo Sounder BackscattermetersUniversal Transverse Mercator (UTM)UTCPacific Hydrographic BranchNOAAThe survey area is located in Lisburne Peninsula Alaska within the sub locality of 8.5 NM Due North of Point Hope.68.5601472222167.01511388968.4399944444166.584761111Data were not acquired to the survey limits in accordance with the requirements in the Project Instructions and the April 2018 NOS Hydrographic Surveys Specifications and Deliverables (HSSD). Due to time constraints, the sheet limits were revised by the Project Manager to prioritize the area of which has the highest marine traffic. See Appendix II for a record of this correspondence, and Figure 1 for a depiction of the revised sheet limits. H13123 revised sheet limits (red) overlaid onto Chart 16123SupportFiles\Sheet Limits.pngPoint Hope is a five square mile point of landhead jutting into the Chukchi Sea. Despite its prominent location and exposure to nearby vessel traffic, much of the area in the vicinity remains unsurveyed. Within the identified survey area, the sparse data provided is from foreign charts dating 1884 to 1949. As the size of vessels transiting through the Arctic continues to expand there are increasing risks to maritime safety and the livelihood of the local subsistence based community. This project will provide critical data for the updating of National Ocean Service (NOS) nautical charting products to increase maritime safety in the region. Additionally, acquired data will be available to assist developments in storm surge and wave modeling for the local community, increasing their coastal resilience. The entire survey is adequate to supersede previous data.Data acquired in H13123 meet multibeam echo sounder (MBES) coverage requirements for set line spacing, as required by the HSSD. This includes crosslines (see Section B.2.1), NOAA allowable uncertainty (see Section B.2.9), and density requirements (see Section B.2.10). All waters in survey areaSet line spacing MBES at 200 mFollowing the first few days of acquisition on OPR-S347-FA-18, the standard spacing between lines was requested and granted by HSD OPS to be increased from 200 m to 400 m. 400 m line spacing was determined to be adequate for the entirety of H13123 and was used for all acquisition. The modification request can be found in the Supplemental Survey Records Correspondence located in Appendix II of this report. See Figure 2 for an overview of coverage. In the southwest of H13123, the line spacing exceeded 400 m, but was no more than 600 m, as shown in Figure 3.H13123 survey coverage overlaid onto Chart 16123SupportFiles\Coverage Overlaid onto Chart 16123_revised sheet limits.pngH13123 area exceeding 400 m line spacingSupportFiles\Line Spacing Exceeding 400 m.png2806078.74000005.940S2200100.520000010.3800179.260000016.3209.100000195.582018-07-152018-08-102018-08-112018-08-122018-08-15Refer to the OPR-S347-FA-18 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.S22070.44.828068.61.1Kongsberg MaritimeEM 710MBESKongsberg MaritimeEM 2040MBESSea-Bird ScientificSBE 19plus V2Conductivity, Temperature, and Depth SensorAML OceanographicMVP200Conductivity, Temperature, and Depth SensorTeledyne RESONSVP 71Sound Speed SystemApplanixPOS MV 320 v5Positioning SystemSea-Bird ScientificSBE 45Sound Speed SystemThe equipment was installed on the survey platforms as follows: all MBES survey vessels are equipped with POS MV v5 systems for positioning and attitude. S220 utilizes the Kongsberg EM710 MBES, Sea-Bird Scientific SBE 45 TSG for continuous determination of surface sound speed, and AML Oceanographic MVP 200 for conductivity, temperature, and depth (CTD) casts. All launches utilize Kongsberg EM 2040 MBES, Teledyne RESON SVP 71 surface sound speed sensors, and Sea-Bird Scientific 19plus CTD casts.Crosslines were collected, processed and compared in accordance with Section 5.2.4.2 of the HSSD. To evaluate crosslines, a surface generated via data strictly from mainscheme lines, and a surface generated via data strictly from crosslines were created. From these two surfaces, a difference surface (mainscheme-crosslines=difference surface) was generated (Figure 4), and is submitted in the Separates II Digital Data folder. Statistics show the mean difference between the depths derived from mainscheme data and crossline data was 0.04 m, with 95% of nodes falling within +/-0.31 m (Figure 5). For the respective depths, the difference surface was compared to the allowable NOAA uncertainty standards. In total, >99.5% of the depth differences between H13123 mainscheme and crossline data were within allowable NOAA uncertainties. Overview of H13123 crosslines.SupportFiles\Crosslines.pngH13123 Crossline DifferenceSupportFiles\H13123_MB_MLLW_4m_NO_X Lines-H13123_MB_MLLW_4m_X Lines_depth_delta.png00.076ERS via ERZTS2201.00.5280620.5In addition to the usual a priori estimates of uncertainty provided via device models for vessel motion, ERZT, and Not So Poor Man's VDatum (NSPMVD), real-time and post-processed uncertainty sources were also incorporated into the depth estimates of survey H13123. Real-time uncertainties were provided via EM710 and EM2040 MBES data, Applanix Delayed Heave RMS, and TCARI tides. Following post-processing of the real-time vessel motion, recomputed uncertainties of vessel navigation were applied in CARIS HIPS and SIPS via a Smoothed Best Estimate of Trajectory (SBET) RMS file generated in Applanix POSPac. To determine the uncertainty value of the NSPMVD model, the variance sum law was used between the independent variables of the ERZT model and the NSPMVD model. As the ERZT model’s uncertainty is driven primarily from tidal uncertainties, the uncertainty in the TCARI grid was used as the starting point for ERZT uncertainty. This is then adjusted based on the average number of survey lines for the given nodes which represent individual “samples” and serves to tighten the ERZT uncertainty. Other ERZT factors such as SBET and waterline are small enough to be absorbed by the gridding resolution (1,000m). The NSPMVD uncertainty value was then calculated using this value and the standard deviations of the NSPMVD-ERZT difference surfaces. See Figure 6 for the equation and variables utilized in this determination.H13123 NSPMVD determinationSupportFiles\PMVD TPU Value.pngH13123 junctions with two adjacent surveys from this project, H13120 and H13122 as seen in Figure 7. Data overlap between H13123 and each adjacent survey was achieved. These areas of overlap between surveys were reviewed with CARIS HIPS and SIPS by surface differencing (at equal resolutions) to assess surface agreement. The junctions with H13123 are generally within the NOAA allowable uncertainty in their areas of overlap. For all junctions with H13123, a negative difference indicates H13123 was shoaler, and a positive difference indicates H13123 was deeper.Overview of H13123 junction surveysSupportFiles\Junction Overview.pngH13120200002018NOAA Ship FAIRWEATHERSSurface differencing in CARIS HIPS and SIPS was used to assess junction agreement between the surface from H13123 and the surface from H13120, as seen in Figure 8. The statistical analysis of the difference surface shows a mean of 0.19 m with 95% of all nodes having a maximum deviation of +/- 0.12 m, as seen in Figure 9. It was found that 100% of nodes are within NOAA allowable uncertainty. Difference surface between H13123 (gray) and junctioning survey H13120 (pink)SupportFiles\H13123-H13120 Junction.pngDifference surface statistics between H13123 and H13120SupportFiles\H13123_MB_4m_MLLW_Final-H13120_MB_4m_MLLW_depth_delta.pngH13122200002018NOAA Ship FAIRWEATHERWSurface differencing in CARIS HIPS and SIPS was used to assess junction agreement between the surface from H13123 and the surface from H13122, as seen in Figure 10. The statistical analysis of the difference surface shows a mean of -0.01 m with 95% of all nodes having a maximum deviation of +/- 0.20 m, as seen in Figure 11. It was found that 100% of nodes are within NOAA allowable uncertainty. Difference surface between H13123 (gray) and junctioning survey H13122 (blue)SupportFiles\H13123-H13122 Junction.pngDifference surface statistics between H13123 and H13122SupportFiles\H13123_MB_4m_MLLW_Final-H13122_MB_4m_MLLW_Final_depth_delta.pngSonar system quality control checks were conducted as detailed in the quality control section of the DAPR.None ExistThere were no conditions or deficiencies that affected equipment operational effectiveness.None ExistThere were no other factors that affected corrections to soundings.Casts were conducted at a minimum of one every four hours during launch acquisition. Casts were conducted more frequently in areas where there was a change in surface sound speed greater than two meters per second. MVP casts on S220 were conducted at an average interval of 2 hours, guided by observation of the surface sound speed and targeted to deeper areas. All sound speed methods were used as detailed in the DAPR.All equipment and survey methods were used as detailed in the DAPR.NOAA Allowable UncertaintyThe surface was analyzed using the Pydro QC Tools Grid QA feature to determine compliance with specifications. Overall more than 99.5% of nodes meet NOAA allowable uncertainty specifications for H13123, as shown in Figure 12. NOAA allowable uncertainty statistics for H13123 SupportFiles\H13123_MB_4m_MLLW.QAv5.tvu_qc.pngDensityThe surface was analyzed using the Pydro QC Tools Grid QA feature. Density requirements for H13123 were achieved with at least 99.5% of surface nodes containing five or more soundings as required by HSSD section 5.2.2.4, as shown in Figure 13. Density statistics for H13123SupportFiles\H13123_MB_4m_MLLW.QAv5.density.pngAll data reduction procedures conform to those detailed in the DAPR.All sounding systems were calibrated as detailed in the DAPR.Raw Backscatter were stored in the .all file for Kongsberg systems. All backscatter were processed by the field unit via Fledermaus FMGT 7.8.5. All processed floating point mosaics and .gsf files have been submitted to the Pacific Hydrographic Branch. See Figure 14 for a complete mosaic.Complete backscatter mosaic overlaid on Chart 16123SupportFiles\Backscatter Mosaic.pngTeledyne CARISHIPS and SIPS10.4.3QPSFledermaus FMGT7.8.5NOAA Extended Attribute Files version 5.7H13123_MB_MLLW_4mCARIS Raster Surface (CUBE)421.831.0NOAA_4mSet Line Spacing MBESH13123_MB_MLLW_4m_FinalCARIS Raster Surface (CUBE)421.831.0NOAA_4mSet Line Spacing MBESThe NOAA CUBE parameters defined in the HSSD were used for the creation of all CUBE surfaces for H13123. The surfaces have been reviewed where noisy data, or "fliers," are incorporated into the gridded solutions causing the surface to be shoaler or deeper than the true sea floor. Where these spurious soundings cause the gridded surface to be shoaler or deeper than the reliably measured seabed by greater than the maximum allowable Total Vertical Uncertainty at that depth, the noisy data have been rejected by the hydrographer and the surface recomputed. Flier Finder, part of the QC Tools package within HydrOffice, was used to assist the search for spurious soundings following gross cleaning. Flier Finder was run iteratively until all remaining flagged fliers were deemed to be edge fliers which don't exceed the TVU threshold.Data LogsData acquisition and processing notes are included in the acquisition and processing logs, and additional processing such as final tide and sound speed application are noted in the H13123 Data Log spreadsheet. All data logs are submitted digitally in the Separates I folder.Per Section 5.1.2.3 of the 2014 Field Procedures Manual, no Horizontal and Vertical Control Report has been generated for H13123 as no field horizontal control activities were used for sounding positioning.Mean Lower Low WaterRed Dog Dock9491094TCARI9491094.tidFinal ApprovedS347FA2018.tcFinal2018-08-162018-08-27Initial reduction of acquired data to MLLW was accomplished via traditional tidal means using the Tidal Constituent and Residual Interpolation (TCARI) grid provided by HSD-OPS. ERS methods were used for reducing data to MLLW following the successful application of SBETs and computation of an Ellipsoidally Referenced Zone Tide (ERZT) separation model.ERS via Poor Mans VDATUMOPR-S347-FA-18-PointHope_NSPMVD_NAD83-MLLW_RevisedERS methods were used as the final means of reducing H13123 to MLLW for submission. Data were initially reduced via traditional tidal means until an ERZT separation model could be calculated. This empirically derived model was then checked for consistency and compared to the Not So Poor Man's VDatum (NSPMVD) separation model provided with the Project Instructions. North American Datum 1983UTM Zone 3 NorthVessel kinematic data were post-processed using Applanix POSPac processing software and RTX methods described in the DAPR. Smoothed Best Estimate of Trajectory (SBET) and associated error (RMS) data were applied to all MBES data in CARIS HIPS and SIPS. For further details regarding the processing and quality control checks performed, see the H13123 POSPac Processing Logs spreadsheet located in the Separates I folder.During real-time acquisition, S220 and launch 2806 received correctors from the Wide Area Augmentation System (WAAS) for increased accuracies similar to USCG DGPS stations. WAAS and SBETs were the sole methods of positioning for H13123 as no DGPS stations were available for realtime horizontal control.A manual comparison was performed between survey H13123 and ENC US5AK93M, the largest scale chart, using CARIS HIPS and SIPS sounding layer derived from the four meter surface generated from H13123 data. The soundings were overlaid on the chart to assess differences between the surveyed soundings and the charted depths and contours. US5AK93M5000032017-02-142017-02-14falseOn the largest scale ENC and raster charts, US5AK93M and 16123, respectively, there are ten soundings located within the revised sheet limits. Due to the lack of soundings, a detailed visual evaluation was conducted and found three significant discrepancies in depth. Each sounding on the chart is shoaler than the surveyed depth, as shown in Figure 15. The hydrographer deems the entire survey is adequate to supersede previous data.H13123 visual chart comparison discrepanciesSupportFiles\Chart comparison discrepancies_ENC.pngNo Maritime Boundary Points were assigned for this survey.No charted features exist for this survey.No uncharted features exist for this survey.No shoals or potentially hazardous 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.Bottom samples were assigned for this survey, but were not acquired due to time constraints. Shoreline was not assigned in the Hydrographic Survey Project Instructions or Statement of Work.No prior survey comparisons exist for this survey.No Aids to navigation (ATONs) exist 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 and/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 insets 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.CDR Marc Moser, NOAACommanding Officer2018-11-06LT Damian Manda, NOAAField Operations Officer2018-11-06HCST Samuel CandioChief Survey Technician2018-11-06ENS Patrick Lawler, NOAASheet Manager2018-11-06