Long-range Ocean Acoustic Propagation EXperiment LOAPEX. Cruise Plan

Transcription

1 Long-range Ocean Acoustic Propagation EXperiment LOAPEX Cruise Plan James Mercer and Bruce Howe Applied Physics Laboratory, University of Washington Summary 18 August 2004 Version 2.3 To better understand long-range ocean acoustic propagation, we will deploy a ship-suspended low frequency acoustic source at various ranges up to 3200 km from the SPICE04 vertical line array (VLA) receiver. There will be seven transmission stations along a geodesic between the VLA and station T3200 (33º N, 137º W and 34º N, 172º W, respectively), and an eighth station near the island of Kauai. In addition to the transmitted signals being received on the VLA, they will also be received by a towed receiver behind Kermit Seamount as part of the BASSEX experiment, and on U.S. Navy hydrophone arrays around the North Pacific. LOAPEX, SPICE04, and BASSEX are the three components of the ONR-funded NPAL04 (North Pacific Acoustic Laboratory) field program. Vessel: Master of Vessel: Chief Scientist: R/V Melville, Scripps Institution of Oceanography Captain Chris Curl Jim Mercer, Applied Physics Laboratory, University of Washington Departure: September 2004 SIO Marine Facility, San Diego Arrival: October 2004 Snug Harbor Marine Facility, University of Hawaii i

2 Table of Contents Table of Contents... ii List of Figures...iii List of Tables...iii 1. Introduction Background Science LOAPEX Goals and Objectives SPICE04 Goals and Objectives BASSEX Goals and Objectives Other Scientific Operations Cruise Plan Overview Acoustic Measurements Shipboard Equipment HX-554 Source Spare Source Webb Research Sweeper Monitoring Ocean Bottom Seismometer Navy Receivers Signals and Transmission Schedules Environmental Measurements Ship-based measurements Underway CTD (UCTD) CTD XBT Other Measurements Seaglider Navigation and Communications Navigation Ship navigation Source navigation Communications Operations Plans Mobilization Stations Shore-side Activities De-mobilization Cruise Reporting References Appendix 1. Contacts List Appendix 2. Scientific Personnel Responsibilities Appendix 3. LOAPEX Signal Parameters Appendix 4. Station Checklist ii

3 Appendix 5. Equipment Provided by the Science Party Appendix 6. Equipment Provided by the Ship Appendix 7. Environmental Compliance Appendix 8. LOAPEX Watch Schedule Appendix 9. Security at Snug Harbor Appendix 10. LOAPEX Detailed Transmission Schedule List of Figures Figure 1. Experimental geometry. Acoustic paths from the sources [75-Hz ship-suspended LOAPEX source (red points), moored SPICE04 S1 and S2 250-Hz sources (black) 500 and 1000 km west of VLA, and Kauai 75-Hz source] to the receivers (S1 and S2, Navy receivers, the vertical line array, and the BASSEX towed receiver)... 2 Figure 2. LOAPEX bathymetry section from T3200 (left/west) to VLA (right/east)... 2 Figure 3. SPICE04 experimental geometry... 3 Figure 4. The deep and shallow VLA receiver moorings... 4 Figure 5. The BASSEX bathymetry... 4 Figure 6. The HX-554 acoustic source without its oil-filled boot (left) and with the boot, mounted in its frame (right)... 7 Figure 7. The winch for the HX-554 acoustic source. The control area is behind the winch Figure 8. The Webb Research sweeper source, Hz. Two units are stacked. The black tube (left) is the source, the yellow tube (right) has electronics and batteries Figure 9. The LC2000 ocean bottom seismometer package... 9 Figure 10. The underway CTD (UCTD) deployment and recovery. The recovery winch and prelaunch spooling of the line. A view of the boom is also in Figure Figure 11 The Seaglider. The Iridium/GPS antenna mast fits in the tail on the left Figure 12. LOAPEX source acoustic tracking Figure 13. Science deck plan Figure 14. OBSs, moorings, and transponders at the VLA site Figure 15. Bathymetry around the Kauai ATOC source and the LOAPEX transmission site Figure 16. Plots of PFM signal vs. time Figure 17. PFM frequency domain plots Figure 18. PFM instantaneous frequency and replica correlation peak List of Tables Table 1. Coordinates for the SPICE04 moorings and the Kauai source... 3 Table 2. LOAPEX Station coordinates, with range to the deep VLA... 5 Table 3. LOAPEX summary transmission (TX) schedule... 6 Table 4. OBS deployment coordinates Table 5. LOAPEX source signals summary Table 6. RAFOS source coordinates and other parameters Table 7. LOAPEX summary timeline Table 8. M-sequence signal parameters Table 9. Summary of stresses for the different signals iii

4 1. Introduction 1.1 Background Although serious investigations of long-range ocean acoustic propagation began with World War II, the genesis of our current effort began with our work on the Heard Island Feasibility Test. In that test, electronically generated acoustic signals from ship-suspended sources were sent and coherently received at distances as far as 18,000 km. This successful result led to the Acoustic Thermometry of Ocean Climate (ATOC) demonstration. The purpose of ATOC was to show that a small number of acoustic transmitters and receivers could adequately characterize variations in the heat content of an entire ocean basin. Although hindered by many new environmental regulations, ATOC has demonstrated that basin wide seasonal and climatic variations can be monitored using acoustic transmissions, and that it can be accomplished without endangering marine life. As the formal ATOC demonstration came to an end, the Office of Naval Research (ONR) began sponsorship of the North Pacific Acoustic Laboratory (NPAL). This program uses the acoustic source and receiver network established by the Applied Physics Laboratory, University of Washington (APL-UW) during ATOC to focus on basic research related to long-range acoustic propagation, while at the same time allowing the continuation of the time series of climate related data. Every three years or so, ONR enhances the efforts of NPAL by funding additional experimental efforts. This is one of those years and three coordinated experiments will be conducted. They are BASSEX (Art Baggeroer, MIT), SPICE04 (Peter Worcester, SIO), and LOAPEX (Jim Mercer, UW). LOAPEX (Long-range Ocean Acoustic Propagation Experiment) will be conducted from the R/V Melville between 10 September and 10 October Science The data from the NPAL04 experiment and this cruise specifically will contribute to the continuing investigation of the three essential elements of long-range acoustics that form the rationale for NPAL: signal variability resulting from small scale, relatively high frequency ocean medium fluctuations, the noise field, and the large-scale background sound speed field LOAPEX Goals and Objectives Range dependence. Previous experiments have explored the temporal, vertical, and transverse coherence of resolved acoustic rays at long range. There has not been a systematic effort to explore the evolution with range of either the highly scattered finale observed in previous experiments or of the fluctuation statistics of resolved ray or mode arrivals. Shadow-zone arrivals. All measurements of shadow-zone arrivals have been made with bottommounted hydrophone arrays. The shadow-zone arrivals seem to be both ubiquitous and robust in mid-latitude oceans, appearing in receptions from both the Kauai and Pioneer Seamount sources in the Pacific and in receptions from the AMODE sources in the Atlantic. They may also be related to the Ti arrival identified at the Hawaii-2 Observatory (H2O). The cause of the extensive scattering into what would be expected to be a geometric shadow zone remains unknown. The vertical scattering far exceeds that diffraction predictions. Parabolic equation (PE) simulations using the Garrett and Munk internal wave model have not succeeded in explaining the extent of the observed scattering. NPAL04 will directly investigate the vertical structure of the deep shadow zone arrivals. 1

5 Frequency dependence. We will explore the frequency sensitivity of the scattering using a combination of moored 250-Hz sources, 75-Hz transmissions from the Kauai source, and Hz transmissions from a ship-suspended source (LOAPEX), all transmitting to long vertical receiving arrays at a variety of ranges. Large-scale oceanography. Finally, the 250-Hz moored sources and the LOAPEX source will augment the basin-scale observations of heat content and temperature being made using the Kauai source and U.S. Navy receivers, providing an improved network of acoustic paths and much greater data volume for assimilation into numerical models. Figure 1 shows the location of the various fixed sources and receivers and the LOAPEX stations. Figure 1. Experimental geometry. Acoustic paths from the sources [75-Hz ship-suspended LOAPEX source (red points), moored SPICE04 S1 and S2 250-Hz sources (black) 500 and 1000 km west of VLA, and Kauai 75-Hz source] to the receivers (S1 and S2, Navy receivers, the vertical line array, and the BASSEX towed receiver). Figure 2. LOAPEX bathymetry section from T3200 (left/west) to VLA (right/east) 2

6 1.2.2 SPICE04 Goals and Objectives Ocean fluctuations. Almost all previous experiments have focused on internal waves as the cause of the observed high-frequency fluctuations and internal tides as the cause of lower frequency fluctuations. Recent SeaSoar measurements and PE simulations using that data show that ocean spiciness (temperature and salinity fluctuations that result in no density perturbation) may also play a significant role in long-range propagation. One of the most fundamental issues in long-range propagation is obtaining an understanding of the types of small-scale ocean variability that are important in causing acoustic scattering. The environment between the sources and receivers will be measured using a variety of new tools, including the SeaSoar system, underway CTD (UCTD), and Seaglider autonomous undersea vehicle (AUV), to obtain the data needed to separate internal-waveinduced sound-speed fluctuations from those associated with ocean spiciness and to map both in depth and range (Figure 3). During the SPICE04 deployment cruise 26 May 18 June 2004, four SPICE04 moorings were deployed as shown in Figure 3; the coordinates are given in Table 1. The VLA mooring diagrams are shown in Figure 4. (See Worcester 2004a,b for more details.) In February 2005 there will be a SeaSoar cruise to measure spice along the path during winter storms (D. Rudnick) km 500 km 1 HLF m HLF m Seaglider 2100 m Depth (km) 2 3 WRC 3000 m WRC 3000 m m 5 Figure 3. SPICE04 experimental geometry Table 1. Coordinates for the SPICE04 moorings and the Kauai source Station Latitude N Longitude E Latitude N Longitude E Depth dec deg dec deg deg min deg min m SVLA DVLA S S Kauai

7 Long-range Ocean Acoustic Propagation EXperiment LOAPEX Cruise Plan Figure 4. The deep and shallow VLA receiver moorings BASSEX Goals and Objectives Bathymetry can affect acoustic propagation in many ways including direct blockage, refraction, diffraction, and scattering. The goal of the Basin Acoustic Seamount Scattering EXperiment (BASSEX) will be to measure these effects with an array that can be both towed horizontally as well as deployed vertically. The Kermit seamounts that will be used for this purpose are just south of the Mendocino Ridge, Figure 5. Figure 5. The BASSEX bathymetry 4

8 1.2.4 Other Ambient sound. The moored hydrophone data will augment the ambient sound data base that is being collected as part of NPAL. The measurements will also be compared with those obtained in 1975 during the Church Opal experiment, which was conducted in the same general area of the ocean. Measurements of the ambient sound level near and below the critical depth, where the levels are expected to be much lower than they are in the sound channel, may provide additional basis for the detection of shadow-zone arrivals. Seismic T-phase signals. Much of the NPAL04 effort is directed to a better understanding of how acoustic energy is (presumably) scattered out of the sound channel into the deep ocean. Waterborne T-phase signals are generated by earthquakes and submarine landslides and are ubiquitous in the ocean acoustic spectrum. To complement the receptions on the VLAs, four ocean bottom seismometers and hydrophones will be deployed around the VLAs during the intense VLA recording period of LOAPEX. This will provide a unique opportunity to measure the vertical structure of T- phases, and the hydrophones will give us a bottom sound field measurement. 1.3 Scientific Operations The LOAPEX acoustic source will be deployed at seven stations at successively increasing ranges from the VLAs. These station names are T50, T250, T500, T1000, T1600, T2300, and T3200 (number denotes nominal distance from the VLA in kilometers). An eighth station is located near Kauai. The coordinates of all stations are given in Table 2 and the summary transmission schedule in Table 3 (a constant sound speed of m s -1 is used). The transmissions will nominally be every hour while on station; the start time is set so that the signal will arrive at the VLA at the top of the hour. At each station, the acoustic source will be deployed anywhere from hours; about half the time at 800 m and half the time at 350 m depth (exact division to be decided on station). A deep CTD cast will be made at each station. Between stations UCTD and XBT casts will be made to measure the upper ocean environment. In addition, two Seagliders will be deployed at T50 to make extended measurements over the course of the following 6 7 months. The final station will be just to the northeast of the ATOC/NPAL Kauai source, on a geodesic to the VLA. Table 2. LOAPEX Station coordinates, with range to the deep VLA Station Latitude Longitude Latitude N Longitude E VLA dec deg N dec deg E deg min deg min km T T T T T T T Kauai

9 Station Day 2004 Table 3. LOAPEX summary transmission (TX) schedule TX TX N N N LOAPEX start TX LOAPEX end TX TX window duration duration 20 min 80 min total UTC Day UTC hr:mn:ss min hr:mn TX TX TX 2004 T /14/ :59: /16/2004 6:19:27 34:20: : T /16/ :57: /18/2004 3:17:11 33:20: : T /18/ :54: /20/2004 6:14:29 36:20: : T /21/2004 9:48: /23/2004 6:08:51 44:20: : T /24/ :41: /26/2004 4:01:59 36:20: : T /27/ :34: /30/2004 0:54:06 55:20: : T /2/2004 0:23: /4/2004 3:43:59 51:20: : Kauai /8/2004 4:32: /10/2004 5:52:35 49:20: : Totals 340:40: : Cruise Plan Overview The balance of this Cruise Plan first describes the acoustic instrumentation and measurements. The environmental measurements, including underway conductivity, temperature, and depth (UCTD), expendable BathyThermographs (XBTs), and Seaglider, are described next. A detailed description of the operations is then given. Appendices provide supplemental information and detail, including environmental compliance documentation. 2. Acoustic Measurements 2.1 Shipboard Equipment HX-554 Source The LOAPEX acoustic source is one of the three Alliant-Tech HX-554 sources made for ATOC in The specific one that will be used is serial number 002 (Figure 6), the same one used during the Acoustic Engineering Test (AET) in 1994 off R/P FLIP. During that experiment the source was damaged (flooded upon the first recovery) and subsequently repaired and tested in Lake Washington and Puget Sound in June In 2003 it was modified for ship-suspended use (the outer boot was removed to reduce weight and a new frame was added) in the Indian Ocean as part of a CTBT project; the R/V Melville was also used for this cruise. At the start of that cruise, a failure in the air pressure compensation system caused a fracture in one of the ceramic bars of the transducer. The source was refurbished in by removing the damaged ceramic section from the circuit and thoroughly cleaning and testing all of the ceramic bars. Tests similar to the earlier ones in Lake Washington were repeated in April

10 Figure 6. The HX-554 acoustic source without its oil-filled boot (left) and with the boot, mounted in its frame (right) A deep water (source depths 800 m and 300 m) test was performed May 2004 on the R/V New Horizon near San Clemente Island, California. This cruise provided a test of all parts of the acoustic source system, including the transducer, gas pressurization system, signal electronics, and the handling system. At a depth of 800 m, 75-Hz m-sequence and 65-Hz CW signals were transmitted at 263 W (195 db re 1 µpa at 1 m); a prescription frequency modulated (PFM) signal was transmitted at 182 W (191.8 db re 1 µpa at 1 m). At 300 m depth, 75-Hz m-sequence signals were transmitted at 117 W (188 db re 1 µpa at 1 m) and 65-Hz CW signals were transmitted at 263 W (195 db re 1 µpa at 1 m); the prescription FM signal was not transmitted at this depth. The maximum power transmitted for some of these signals was limited (< 263W, 195 db re 1 µpa at 1 m) because of uncertainty about permissible maximum voltage stress and mechanical ceramic bender bar stress levels. We are modifying our numerical model of the transducer based upon the transmit voltage response (TVR) measurements at 300 and 800 m. In addition, we have met with Alliant-Tech engineers who were involved with the initial development of this transducer. We expect the outcome of these efforts to be a better understanding of the appropriate limits for the critical parameters of maximum voltage and maximum stress. We plan to complete the calibration measurements at our first station (T50) during the LOAPEX cruise. Present modeling efforts indicate we should be able to transmit all three signal types with source levels at or close to 195 db at 350 m and 800 m (see Appendix 3). The source is now held in a frame with the air bottles under it (Figure 6b). The frame is 2.03 m (80 in) tall and the rectangular base is 1.02 m by 1.42 m (40 in by 56 in). The combined weight is 2410 kg (5300 lb) in air and approximately 1820 kg (4000 lb) in water. The power amplifier, controlling electronics, and computer are in the other half of the winch van (Figure 7). The source is connected to the Ling power amplifier via 1300 m of inch. coaxial armored wire. The winch is used to deploy and recover the source package. The winch uses a 30-HP, 240-V AC, 100-A, 3-phase input. For the test cruise on the R/V New Horizon, a 45-kVA transformer was used to step down the ship s voltage from 444 V to 240 V. The control portion of the van uses the same input. The same circuit breaker panel controls all the power for the winch, the low-pressure compressor for the air tuggers, the high-pressure compressor for filling the gas compensation bottles, the Ling power amplifier, and the 120 V AC requirements, which are fed through a separate 3-kVA step down transformer. 7

11 Figure 7. The winch for the HX-554 acoustic source. The control area is behind the winch Spare Source Webb Research Sweeper If the HX-554 source (the primary acoustic source) fails, the back-up source will be a Webb Research Corporation sweeper source (Figure 8). If this source is used, it will be used only at the T50, T250, T500, T1000, and T1600 stations because of its limited range. In each nominal 20- minute transmission window at these five stations there will be three sweeper transmissions. In each nominal 80-minute transmission window there will be twelve sweeper transmissions. Each transmission will last s and sweep linearly from 225 to 325 Hz. Thus, there will be two and eleven 120-s-long gaps in the 20- and 80-minute transmission windows, respectively. Each transmission starts with a 15-s calibration phase that is not counted here. The source level will be 83 W (190 db re 1 µpa at 1m). The sweeper has a vertical directivity index of 3 db. In the worst case, there could be as many as 654 of the 280-s transmissions for a total time (including the 15-s calibration phase) of 53.6 hr. The source draws 4 A at 45 V, an electrical power of 180 W. For all the transmissions, 9647 W hr are required. The battery pack capacity is 12,840 W hr, providing a safety margin of 25 percent. If the sweeper source is used, either the LOAPEX winch or the ship trawl winch and wire can be used for deployment; no conductors are required. The sweeper source weighs 764 kg in air and 295 kg in water (1680 lb and 648 lb, respectively). These will be confirmed at the dock during mobilization. Figure 8. The Webb Research sweeper source, Hz. Two units are stacked. The black tube (left) is the source, the yellow tube (right) has electronics and batteries. 8

12 2.1.3 Monitoring A calibrated reference hydrophone will be used on the cruise (ITC model 8211). The hydrophone will be used to determine the source transmit level and to check the overall timing of the source receiver system. The hydrophone will be deployed to 575 m to reduce the effects of surface bounce and ship noise. The hydrophone cable will be taped to the ship s hydro wire (with a 500-lb weight at the end; CTD wire could also be used) while using the starboard hydroboom (which has replaced the J-frame) for deployment as was done during the Indian Ocean cruise in The horizontal separation on the ship between this wire and the source cable is approximately 37 m (120 ft). A cable dynamics simulation predicts the separation at depth to be no less than 25 m, using a current profile an order of magnitude stronger than is expected for our location. As the hydrophone is recovered the tape holding the signal cable to the wire will have to be cut off. A second hydrophone will serve as a back-up (ITC model 6050C). The APL-UW supplied hydrophone cable powered spool will be used to handle the hydrophone cable Ocean Bottom Seismometer The four ocean bottom seismometers (OBSs) that will be deployed around the VLAs have been prepared by the OBS Facility at SIO. A diagram of one is provided in Figure 9. The deployment coordinates are given in Table 4. The OBSs will have a 500-Hz sampling rate and a 30-day data collection period. Before pick up on P. Worcester s mooring recovery cruise in July 2005, their position will be surveyed. Figure 9. The LC2000 ocean bottom seismometer package 9

13 Table 4. OBS deployment coordinates Latitude N Longitude W Depth deg min deg min m OBS ~5001 OBS ~5048 OBS ~5032 OBS ~ Navy Receivers Data from ten U.S. Navy receivers around the North Pacific will be collected during this experiment. The APL-UW data collection computers will be programmed to turn on at the appropriate times to receive all the source transmissions: the LOAPEX source, the Kauai source, and the four sources on the SPICE04 S1 and S2 moorings. This data will be used to reconstruct a tomographic snapshot of the temperature structure of the North Pacific. Linda Buck and Joe Wigton (APL-UW) will be responsible for data acquisition and preliminary signal processing. 2.3 Signals and Transmission Schedules The LOAPEX source will transmit three types of signals at two depths: m-sequences, a continuous wave (CW) signal, and a prescription frequency modulated (PFM) signal. Transmissions will be made at 800 m and 350 m (the deeper depth first) at each station, with about half the time at each depth. A summary is provided in Table 5 and a detailed description of the signals is given in Appendix 3. At station T50, there will be some calibration activity required, involving incremental increase in drive level until the desired maximum acoustic signal is obtained. Table 5. LOAPEX source signals summary Source level Frequency 800 m m-seq 195 db 75 Hz CW 195 db 65 Hz PFM 195 db 45 Hz 105 Hz 350 m m-seq 194 db 68 Hz CW 195 db 65 Hz PFM 195 db 32 Hz 92 Hz The detailed schedule showing LOAPEX transmissions and VLA receptions is included in Appendix 10. If for some reason we cannot reach the desired station location before its transmission window starts, we may choose to stop where we are and begin transmitting. In this case, the transmission start times will be adjusted so the signals as received by the VLA fall within its scheduled receive window (on the nominal hour). The coordinates will have to be conveyed to APL- UW to reschedule the receivers on the Navy arrays, as well as to the BASSEX crew. 10

14 3. Environmental Measurements 3.1 Ship-based measurements Underway CTD (UCTD) The UCTD operates under the same principle as an XBT. By spooling tether line both from the probe (with temperature, conductivity and depth sensors) and a winch aboard ship, the velocity of the line through the water is zero, line drag is negligible, and the probe can get arbitrarily deep. The challenge is to recover the probe once all of its line has spooled out because the line velocity will then equal the ship speed, and line drag may become large. This has proven to be possible using a 0.06-inch diameter Spectra line with a breaking strength of 650 lb. Measurements will be made almost continually while in transit between ship stops, starting at the VLA position. Based on the experience from the SPICE04 deployment cruise, casts will be made roughly twice an hour (~10 km). With the ship cruising at 12 kt, the sampling depth is expected to be ~400 m. Since the SPICE04 cruise, the UCTD has been improved: the mechanical connection between nose and tail is threaded and the electrical connection is more durable and the reel winch will have speed control. The entire UCTD system (including a full spares package) will be provided by SIO (D. Rudnick). 11

15 Figure 10. The underway CTD (UCTD) deployment and recovery. The recovery winch and prelaunch spooling of the line. A view of the boom is also in Figure CTD A full ocean depth (~5,000 m) CTD cast will be made at every station to obtain deep salinity for sound speed calculations and for silica samples (P. Johnson, UW MG&G). This is estimated to take 4 hr. The sample rate will be 24 samples/s. A 24-bottle rosette will also be used; samples will be collected at depths that depend on the local bottom depth. Casts will be taken within 20 m of the bottom, facilitated by using an altimeter. Upon recovery, two samples from each bottle will be taken; one will be frozen and one refrigerated. Upon arrival in Honolulu, all samples will be air shipped with dry ice to UW for chemical analysis. The primary CTD (Seabird 9-11+) and rosette will be provided by the ship; the backup CTD (Seabird 9-11+) will be provided by APL-UW. The ship will provide primary and secondary deck units and data logging systems. The CTD winch and hydroboom will be used for deployment XBT Expendable bathythermographs (XBTs) will be used to provide deeper, but less frequent, data than the UCTD as well as being a backup to the UCTD. The following XBTs are available: 12 T-5 (1830 m at 6 kt) and 72 T-7 (760 m at 15 kt). These would provide bi-hourly sampling for the seven days of transit along the LOAPEX section. They will be deployed evenly between VLA and T3200. The ship will provide the data acquisition system, part of the swath mapping system. 12

16 3.1.4 Other Measurements The ship has a new RD Instruments Ocean Surveyor 75-kHz acoustic Doppler current profiler (ADCP) rated for obtaining profiles to 700 m. We expect to obtain data to 800 m while on station. The data will complement the UCTD, XBT, and CTD data, as well as providing time dependent profiles of current velocity at each station. Suspended 20 m below the source will be a Seabird MicroTemp logging temperature and pressure and an InterOcean S4 current meter. Data from the ADCP, MicroTemp, and S4 will be used with a source motion model (see below). The standard suite of routine ship measurements will be collected, including thermosalinograph, meteorology, and multibeam bathymetry. The latter should be running between stations and turned off during LOAPEX transmissions at each station. 3.2 Seaglider Figure 11. The Seaglider. The Iridium/GPS antenna mast fits in the tail on the left. The two APL-UW Seagliders will be deployed at station T50. Serial number 22 will be programmed to head east to the VLA mooring site, turn around, and then go along the LOAPEX path to station T1000. It will then turn and head toward the Kauai source, and then to either Hanalai Bay on the north side of Kauai or to Barking Sands, PMRF, on the west side for pickup by a small boat. Serial number 23 will be programmed to immediately head west, traversing the section between T1000 and the VLA approximately three times (3000 km) before being picked up during the SeaSoar cruise in February 2005 (D. Rudnick). As the pick-up time nears, the glider instructions will be adjusted remotely from APL-UW so that it can be picked up at Station T1000 at the end of a SeaSoar section. Both gliders will be programmed to cycle between 0 m and 1000 m water depth covering roughly 7 km over 10 hours. For a nominal mission range of 3000 km, this leaves a 25 percent battery energy reserve. The gliders will be RAFOS-enabled. Unfortunately, none of the SPICE04 sources were programmed 13

17 to transmit the required signals. The gliders will likely hear some of the RAFOS sources maintained by Curt Collins (NPS). The positions of these sources, the transmission schedules, and the distance and travel time to T500 are given in Table 6. The RAFOS signal is an FM-sweep with Hz bandwidth centered at Hz (linear sweep from Hz to Hz) and lasting 80 s. Table 6. RAFOS source coordinates and other parameters Source Latitude N Longitude W Water Source TX time Distance Time deg min deg min m m UTC km s SS2b , SS , SS5a (V1) , SS5b (V2) , Hoke* *no longer working Bruce Howe will be responsible for Seaglider deployment. On shore, Jim Luby (APL-UW) will act as pilot, with assistance from Neil Bogue and Jason Gobat. Data from the gliders can be accessed at the Web page Communications during the deployment time will be important. The satellite pager/telephone provided with the glider will be used, in addition to the normal ship internet connection and satellite telephone systems. 4. Navigation and Communications 4.1 Navigation Ship navigation A C-Nav GPS real-time dual frequency system will drive the dynamic positioning system (DP). This system obtains real-time corrections via satellite communications. Corrections for GPS satellite orbits and clocks and the troposphere are determined using data from the JPL operated Global GPS Network (GGN) and are globally uniform and applicable worldwide. The estimated accuracy is submeter. The antenna will be placed on the stern A-frame above the source overboarding block. While on station, the ship s navigation/dp system will be set up so as to keep the center of the deployed stern A-frame at the desired location (e.g., Table 2). Backup systems will include the Furuno GP-90 single frequency system (accuracy 10 m 95 percent of the time), the Tasman P-code receiver, and the Ashtech ADU system (primarily used for heading with the ADCP). All data from all the ship navigation systems (including roll, pitch, yaw/heading, and heave) will be logged routinely during the entire cruise Source navigation Knowledge of the absolute source position is required for the tomographic application; adequate accuracy and precision can be obtained with C-Nav GPS, assuming the source hangs vertically. Knowledge of the relative source motion, on time scales of 10 s to 80 min and spatial scales of 2 m to 5 m (1/10 th to ¼ wavelength at 75 Hz) is required for the acoustic propagation aspects of the experiment, especially the temporal and spatial coherence estimates. Determining the relative source motion on these scales will be somewhat challenging. Several approaches will be taken, eventually 14

18 all combined with a Kalman filter. From the ship s navigation system, driven by the C-Nav GPS system, we will obtain the best estimate of the time-dependent (1 sample per second) position of the source sheave in the stern A- frame. This A-frame position will be routinely logged by the ship s navigation system. These data, along with appropriately smoothed ADCP water velocity profiles, the S4 current meter data, and the MicroTemp pressure/depth, will be used as the primary inputs to a cable dynamics simulation program (J. Gobat) that will predict the horizontal and vertical motions of the source. To provide additional data and independent verification, we will deploy a poor man s long baseline acoustic navigation system that will measure motion relative to a single bottom Benthos expendable XT6000 acoustic transponder (Figure 12). The latter will be deployed 5 km short of the station, along the path to the VLA. It will not be surveyed, but rather its nominal position determined from the drop position and depth. Suspended 20 m below the source with the S4 current meter and MicroTemp will be a WHOI interrogator that will measure the roundtrip travel time to the bottom transponder. This travel time and the nominal source/transponder geometry will give relative motion (with some noise introduced by vertical heave). Ship position will also be monitored to verify GPS performance; a Benthos DS-7000 deck box and transducer mounted on a stinger in the instrument well will be used for this purpose. For reference, the pendulum period is 57 s at 800 m and 38 s at 350 m. Battery packs are rated for 1 month and 350, ms pings, adequate for this application. Figure 12. LOAPEX source acoustic tracking 4.2 Communications Communications with the shore will be important. Art Baggeroer and Kevin Heaney on the R/V Revelle will also need to be kept informed of our progress in order to coordinate the deployment of their receiving array. The same applies for coordination with APL-UW staff operating the Navy receivers. There is a kb/s internet link shared between three ships. The primary means of communication will be via . The secondary means will be via voice over internet, satellite phones, and fax (see contact information in Appendix 1). These will be tested before sailing. 15

19 5. Operations Plans The cruise timeline is given in Table 7. Table 7. LOAPEX summary timeline Local Time Activity hr:mn from to km nm hr kt Wednesday, September 01, :00 SDH Mobilization Friday, September 10, :00 SDH SD Depart Friday, September 10, :27 Harbor traffic 1 Friday, September 10, :27 SD VLA Transit Tuesday, September 14, :50 Deploy OBS seismometers 6 Tuesday, September 14, :50 VLA T50 Transit Tuesday, September 14, :20 T50 TXs, Seagliders 36 Wednesday, September 15, :20 T50 T250 Transit Thursday, September 16, :20 T250 TXs 36 Friday, September 17, :20 T250 T500 Transit Saturday, September 18, :21 T500 TXs (10 km short of S1) 39 Sunday, September 19, :21 T500 T1000 Transit Monday, September 20, :21 T1000 TXs (10 km short of S2) 47 Wednesday, September 22, :21 T1000 T1600 Transit Friday, September 24, :51 T1600 TXs 39 Saturday, September 25, :51 T1600 T2300 Transit Monday, September 27, :51 T2300 TXs 58 Wednesday, September 29, :51 T2300 T3200 Transit Friday, October 01, :51 T3200 TXs 54 Sunday, October 03, :51 T3200 KA Transit Thursday, October 07, :01 Kauai TXs (23 km north of ATOC) 52 Saturday, October 09, :01 KA HNL Transit Sunday, October 10, :20 Harbor traffic 1 Sunday, October 10, :20 HNL HNLH Harbor traffic Sunday, October 10, :59 HNLH Arrive Snug Harbor. Demobilization Totals days Tuesday, October 12, :00 HNLH Finish demobilization 5.1 Mobilization A surface shipment of equipment will be sent from APL-UW on 19 August. The two Seagliders will be shipped 3 September along with acoustic transponders and the interrogators. XBTs from Sippican and additional acoustic transponders from Benthos will be shipped directly to the SIO Marine Facility, to arrive by 3 September. The science/winch van and the storage van are already at the Marine Facility in San Diego. Personnel arrive as follows: Mercer and Karig, 30 August; Reddaway and Fletcher, 1 September; Andrew, 2 September; Gullings 5 September; Wolfson, Colosi, Xu, and 16

20 Howe, 7 September. Berthing on the ship is available from 3 September. Mobilization will start Wednesday, 1 September, with the loading of the winch/control van, the storage van, air tuggers, the source, and the UCTD and XBT systems. Initial loading will be completed by Friday, 3 September, so that testing may begin during the holiday weekend. The deck plan for the cruise is shown in Figure 13. UCTD boom Sweeper source Source Hydrophone reel OBS-4ea Source cable Science/winch van Air tugger -2ea Storage and Spares van CTD uses new hydroboom Figure 13. Science deck plan The HX-554 source will be tested on the ship while dockside. Impedance measurements will be made in air, in water unpressurized, and in water pressurized. The source will be weighed in air and water (unpressurized and pressurized). The sweeper source will be tested while on deck and weighed in air and water. The C-Nav system will be installed and interfaced to the ship s navigation system, likely on Tuesday 7 September. One of the ship s PCs in the navigation center will be used with the C-Nav system. Data from all the ship s various GPS navigations systems will be collected and plotted together. The latitude, longitude, and height of the A-frame center in deployed position, as well as roll, pitch, and heading will be logged. The ship will continually acquire and log all navigation data. The ship will provide Ethernet/internet connectivity (e.g., an RJ-45 connector) and a ship computer display in the source control van (repeaters may be necessary). The display will show the DP position in latitude and longitude, UTC time, and a plot of ship position relative to the nominal station coordinates. The ship will verify that UTC time displayed is accurate to 1 s. The UCTD system will be installed by D. Rudnick. The CTD/rosette will be installed by R. Wilson. A transducer stinger pole (supplied by MarFac) will be installed in the instrument well (frame 95, 01 level, just to the port side of the CTD winch) with the Benthos transducer. The various methods of communication will be tested (internet , file transfer, Web browsing, 17

21 voice over internet, satellite phones, etc.). The ship will load two containers on the 01 level that will be used in the following cruise by Ken Johnson. The goal is to have everything loaded and the preliminary testing done by the end of Tuesday, 7 September, so the last two days before departure can be spent on final testing and tuning. During the mobilization, there will be a pre-cruise meeting to review plans and aspects related to safety. 5.2 Stations In order to have enough time to deploy the OBS units at the VLA site, the ship speed will need to be at least 11.5 kt during the transit from San Diego; 12 kt is planned. At all other times, the nominal ship speed called for is 10.8 kt (20 km/hr), though 12 kt should be made if weather permits, to allow more time on station. The ship will travel along a geodesic between stations; detailed waypoints will be provided. The four OBS units will be deployed at the VLA site. There will be no attempts to survey them or communicate with them. The desired locations of the OBSs are shown in Figure OBS2 meters re DVLA SVLA OBS1 0 DVLA OBS OBS meters re DVLA Figure 14. OBSs, moorings, and transponders at the VLA site The station checklist (Appendix 4) will be used to guide the activity at each station. At Station T50, some of the transmission time will be used for source calibration. In this case it may be necessary to marry the hydrophone and cable directly to the source cable. This has been done before, with only a one-turn twist on recovery (which is manageable). The Seagliders will also be deployed at T50 during the CTD cast, with the stinger with acoustic transducer deployed for ranging. For this activity, the small boat may be required. The station locations for T500 and T1000 are actually 490 km and 990 km from the VLA, to avoid any possible fouling between the LOAPEX source and the SPICE S1 and S2 moorings, which are at the nominal ranges of 500 km and 1000 km. There may be some interference with the navigation net associated with these moorings. The interrogator on the mooring transmits a 10.5-kHz signal once an hour to the transponder 3500 m north of the mooring, as well as the secondary mooring release. This 18

22 signal could cause the LOAPEX transponder 15 km distant to reply, confusing the LOAPEX slant range measurement. Given the low repetition rate (once per hour) we will ignore this effect (though it might provide an interesting cross check). Conversely, the LOAPEX interrogator could cause the mooring transponder and #2 release 10 km distant to reply at 9.5 khz and 11.0 khz, respectively, confusing the mooring interrogator. Given there are three other mooring transponders, mooring tracking should not be affected by any confusion with the fourth travel time, which would likely appear as an outlier. The Kauai station location is 40 km northeast of the ATOC/NPAL Kauai source, on a geodesic to the VLA. The bathymetry is shown in Figure 15. Figure 15. Bathymetry around the Kauai ATOC source and the LOAPEX transmission site In between stations UCTD, XBT, ADCP, swath mapping, and other data as described above will be collected. 5.3 Shore-side Activities The Navy receivers will be programmed to receive all the LOAPEX, S1 and S2, and Kauai transmissions. This is controlled from APL-UW (Linda Buck). If the LOAPEX station location and transmissions times are changed, the corresponding Navy reception times must be changed appropriately. The Seaglider will be piloted by Jim Luby at APL-UW with help from Neil Bogue and Jason Gobat. The ATOC/NPAL Kauai source will be programmed to transmit every 4 hr every day for 60 days starting September 2004 and ending November UTC (Linda Buck). 5.4 De-mobilization After the arrival on Sunday 10 October, demobilization will begin at 0800 on Monday morning 11 October. The winch/control van will be placed on the port side of the 01 winch deck, with the WRC 19

23 sweeper source secured to the top. The storage van will be off-loaded, repacked, and placed crosswise on the 02 foredeck for the return trip to San Diego. 5.5 Cruise Reporting When we walk off the ship we should have data worked up sufficiently to make plots. These should include: UCTD, XBT, and ADCP sections CTD profiles Swath bathymetry maps Standard ship-collected data (e.g., meteorological) Best estimate of (x,y,z) time series at the stern A-frame for each station Source MicroTemp temperature and pressure and S4 velocity data for each station Model predicted source motion time series based on (x,y,z) and ADCP data Acoustic travel times and relative source and ship motion Summaries of source performance across all stations All the data will be backed up onto multiple CDs and distributed to the various parties; acoustic data will be archived on Jazz drives. References Baggeroer, A., and K. Heaney, BASSEX Cruise Plan, informal document, MIT, Mercer, J. A., R/V New Horizon Cruise report: LOAPEX Test Cruise, informal document, APL- UW, Worcester, P. F., SPICE04 Deployment Cruise Plan, informal document, SIO, 2004a. Worcester, P. F., SPICE04 Deployment Cruise Report, informal document, SIO, 2004b. 20

24 Appendix 1. Contacts List Applied Physics Laboratory University of Washington 1013 NE 40 th Street Seattle, WA, Rex Andrew Neil Bogue Linda Buck Brian Dushaw Charlie Eriksen Jason Gobat Lyle Gullings Frank Henyey Bruce Howe Fred Karig Craig Lee Jim Luby Jim Mercer Don Reddaway Jeff Simmen Keith Van Thiel Keith Walls Joe Wigton Mike Wolfson Mike Zarnetske Main Lab fax: Data Center Scripps Institution of Oceanography 9500 Gilman Drive La Jolla, CA, Jeff Babcock Patricia Chang Matt Dzieciuch Garth Englehorn Lloyd Green David Horwitt Matt Norenberg Dan Rudnick Peter Worcester

25 Nimitz Marine Facility, SIO 297 Rosecrans Street San Diego, Ca Tom Althouse Cambria Colt Geoff Davis Ron Moe Woody Sutherland cell: Bob Wilson MarFac R/V Melville Port: Sea: Fax: MIT Room Cambridge, MA Art Baggeroer Kevin Heaney cell: Office of Naval Research 800 Quincy Street Arlington, VA Nick Chotiros Bev Kuhn Ellen Livingston Woods Hole Oceanographic Institution, MS Water Street Woods Hole, MA John Colosi Steve Liberatore Jinshan Xu 22

26 Webb Research Corporation 82 Technology Park Drive E. Falmouth, MA Andrey Morozov Doug Webb Marine Acoustics, Inc. 809 Aquidneck Ave. Middletown, RI Kathleen Vigness Raposa C & C Technologies 730 E. Kaliste Saloom Road Lafayette, Louisiana Dan Galligan fax: Support dan@cctechnol.com cnav.support@cctechnol.com 23

27 Appendix 2. Scientific Personnel Responsibilities Rex Andrew Scientist Transmissions APL-UW Patricia Chang Development Tech OBS SIO John Colosi Scientist UCTD WHOI Garth Englehorn Development Tech OBS SIO Lyle Gullings Engineer Source APL-UW Bruce Howe Scientist Environmental sampling APL-UW Fred Karig Mechanical Engineer Winch, source APL-UW Jim Mercer Chief Scientist APL-UW Chuck Fletcher Field Engineer Deck APL-UW Mike Wolfson Scientist XBT APL-UW Jinshan Xu Graduate student UCTD WHOI Bob Wilson will be the ship s resident technician. Geoff Davis will be the ship s computer technician. Source deployment APL Winch Fred Karig A-Frame Bob Wilson Port Air Tugger Chuck Fletcher Starboard Air Tugger Lyle Gullings Port Tag Line John Colosi Starboard Tag Line Garth Englehorn Safety Jim Mercer Hydrophone deployment Bruce Howe Rex Andrew Patricia Chang 24

28 Appendix 3. LOAPEX Signal Parameters Three types of signals are being designed for possible use on the cruise: m-sequence, continuous wave (CW), and prescription frequency modulated (PFM) signals. The m-sequence is the preferred signal; the others will be transmitted only if it is thought there are significant engineering benefits (e.g., source longevity) over the m-sequences. M-sequences The m-sequence signals consist of periodic repetitions of a phase-coded linear maximal shift register sequence, with parameters given in Table 8. Table 8. M-sequence signal parameters Source depth m Source level W db re 1 µpa at 1 m center frequency f * Hz cycles/digit 2 2 digit length ms sequence length L digits (degree 10) sequence period s sequence law artifact location digit sequence initialization phase modulation angle θ sequence repetitions transmitted 20 minute 80 minute transmission duration 20 minute minute s s Estimated Maximum stack voltage V Peak Estimated Maximum stack stress psi Peak *This may be changed to be more commensurate with VLA sampling. The modulation angle is defined to be tan 2 θ 0 = L, giving a smooth sinc 2 envelope to the power spectrum. The 75-Hz signal is the same signal that the former Pioneer Seamount source transmitted. The estimated maximum stack voltage and stress in the table can be compared with recommended safe working limits of 4243 V and 3831 psi, respectively. The linear maximal shift register m-sequence for law = , with initialization = is:

29 If a 1 in the above sequence is equivalent to s = +1 and a 0 to s = 1, then the signal sent is cos(2πf 0 (t-t 0 ) + s(i(t-t 0 ))θ) where i(t) is the digit index at time t. Transmissions start 5 min plus one period (300 s s = s for the 75-Hz signal and 300 s s = s for the 68-Hz signal) before the prescribed start time t 0 (UTC) at a level of 0.26 W (165 db re 1 µpa at 1 m) and increase in level 6 db every minute until the desired output level is reached. CW parameters The CW signal is represented by sin(2πf 0 (t-t 0 )), with the 5-min ramp-up as for the m-sequence. f 0 for LOAPEX is 65 Hz for both depth cases. The period (as defined in this case by the length of the pre-defined signal) is 10 s. The estimated maximum stack voltages and stress for the 800 m and 350 m depth cases are 1882 V and 1750 psi and 2254 V and 3123 psi, respectively. These can be compared with recommended safe working limits of 4243 V and 3831 psi, respectively. Transmissions will start 5 min plus 10 s (300 s + 10 s = 310 s) before the prescribed start time t 0 (UTC) at a level of 0.26 W (165 db re 1 µpa at 1 m) and increase in level 6 db every minute until the desired output level is reached. Prescription FM The prescription FM signal is constructed using an equivalent circuit model of the source to produce an output power spectrum with a cosine shape over the frequency range of interest, subject to not exceeding voltage, mechanical stress, and current limits set by the engineering properties of the source. This is produced by varying the time spent at any particular frequency and source drive level so the total energy transmitted in a particular frequency band fits the desired cosine shape. For the two depths 800 m and 350 m, the frequency ranges are Hz and Hz, respectively. Signals sweep up in frequency for 15 s and down in frequency for 15 s with an effective period of exactly 30 s. Various signal waveforms for the 350 m PFM are shown in the following figures. The second plot in 26

30 Figure 16 shows the actual expected pressure signal from the source. The other plots show stack stress and voltage, tuner current, and quanta in the computer file that will generate the signal. Figure 17 shows the frequency domain versions of the desired signal, the d/a drive signal spectrum, and the expected pressure spectrum. Figure 18 shows the instantaneous frequency versus time and the replica correlation peak in the time domain. Figure 16. Plots of PFM signal vs. time Figure 17. PFM frequency domain plots 27

31 Figure 18. PFM instantaneous frequency and replica correlation peak The estimated maximum stack voltages and stress for the 800 m and 350 m depth cases are 2275 V and 2443 psi and 3199 V and 3860 psi, respectively. These can be compared with recommended safe working limits of 4243 V and 3831 psi, respectively. Transmissions start 5 min plus one period (300 s s = s) before the prescribed start time t 0 (UTC) at a level of 0.26 W (165 db re 1 µpa at 1 m) and increase in level 6 db every minute until the desired output level is reached. Summary The stresses for the various signals are summarized in Table 9. Table 9. Summary of stresses for the different signals Source level (db re 1 µ at 1 m) Peak stack stress (psi) Peak stack voltage (V) RMS tuner current (A) 350 m m-seq CW PFM m m-seq CW PFM Limits

32 Appendix 4. Station Checklist Deployment and recovery of the source is desired during daylight; the CTD/rosette cast may be performed before or after to facilitate this. We assume it is done first here. 1. Secure UCTD, XBT, etc. 2. Confirm coordinates 3. Deploy XT6000 transponder 5 km from station, log position and depth 4. Arrive on station 5. Confirm the C-Nav system and dynamic positioning system operating normally 6. Determine bottle sampling depths 7. Prepare CTD/rosette 8. Launch CTD/rosette 9. Perform CTD profile, taking bottle samples at selected depths 10. Deploy acoustic transducer on stinger in instrument well, confirm transponder operation 11. Recover and secure CTD/rosette and decant bottle samples; clean equipment 12. Secure ship echo-sounder and swath bathymetry 13. Ensure ADCP working 14. Checkout source system 15. Confirm ship is at correct location in dynamic positioning; and all navigation data is being logged correctly 16. Deploy instrument suite (interrogator, MicroTemp, and S4 current meter on 20 m line) 17. Deploy source to 800 m (sound channel axis) and monitor impedance 18. Confirm C-Nav and DP are operating normally after the A-frame is in deployed position 19. Deploy hydrophone using hydroboom and hydrowinch 20. Pressurize source, monitoring impedance and listening on hydrophone 21. Transmit 22. Raise the source to 350 m, monitor impedance 23. Transmit 24. Recover source and instrument suite 25. Inspect source, recharge gas bottles 26. Recover monitor hydrophone 27. Recover stinger in instrument well with acoustic transducer 28. Prepare UCTD, XBT, swath bathymetry, etc. 29. Modify if necessary schedule and waypoints for transit and next ship stop 30. Transit, UCTD and XBT 31. Backup data, analyze as appropriate 29

33 Appendix 5. Equipment Provided by the Science Party 1. HX-554 acoustic source system (source, frame, gas bottles and charging, van with power amplifier, winch, and controlling computer system, auxiliary equipment van) 2. Spare source computer system and power amplifier modules, dummy load (resistor stack) 3. Sweeper sound source and control electronics (SIO) 4. Calibration and receiving hydrophones (ITC, 2 each) 5. Powered hydrophone cable reel (APL-UW) 6. Air tuggers, 2 each (APL-UW) 7. UCTD with spares (SIO Rudnick) 8. CTD backup (APL-UW) 9. MicroTemp with pressure (WHOI Colosi) 10. S4 current meter (APL-UW) 11. WHOI Interrogators, 2 each (APL-UW) 12. Benthos DS-7000 deck boxes, 2 each (APL-UW) 13. Benthos XT6000 acoustic transponders (3 to 6 new direct from Benthos, 6 from APL-UW) 14. XBT probes (APL-UW) 15. Desktop and personal computers 16. Assorted tools 17. CTD/Rosette sample bottles, coolers 30

34 Appendix 6. Equipment Provided by the Ship 1. Power for the science/winch van (240 V AC, 100 A, 3 phase) 2. Stern A-frame 3. Primary CTD/Rosette system with altimeter, including data acquisition and logging 4. CTD winch and hydroboom for CTD/rosette 5. Freezer space for water samples 6. Hydrowinch and hydroboom for hydrophone 7. Stinger in instrument well for acoustic transducer, assist in mounting 8. Space on main deck for science/winch and supply vans 9. Swath mapping, continuous while underway 10. Precision depth recorder and 3.5-kHz sub-bottom profiler 11. Copy machine 12. Grappling hooks, hackles, sheaves, hooks, and lines 13. Navigation display in source control van 14. Ethernet/Internet in source control van 15. Assist in mounting and installing C-Nav system 16. PC computer in the navigation room for the C-Nav system 17. PC computer in the navigation room (or main lab) for the Benthos deck box 18. Electronic mail system with connection to shore, voice over internet 19. GPS systems 20. Capstan 21. Underway/on station data acquisition system for meteorological instruments, ADCP, thermosalinograph, fluorometer 22. Shipboard Acoustic Doppler Current Profiler (ADCP) RD Ocean Explorer to 700 m 31

35 Appendix 7. Environmental Compliance RESPONSIBLE COMMAND: Acoustic Analysis for LOAPEX Department of the Navy Office of Naval Research; Ocean, Atmosphere, and Space Department; Ocean Acoustics Branch (ONR321OA) ORGANIZATION DESIGNING AND CONDUCTING EXPERIMENT: Applied Physics Laboratory at the University of Washington TITLE OF PROPOSED ACTION: Long-range Ocean Acoustic Propagation Experiment (LOAPEX) CONTACT PERSON AT RESPONSIBLE COMMAND: Office of Naval Research Dr. Nick Chotiros, ONR 321OA DOCUMENT DESIGNATION: This Acoustic Analysis is prepared pursuant to ONR directives and to support a determination under Executive Order (EO) 12114, Environmental Effects Abroad of Major Federal Actions. ABSTRACT: The Applied Physics Laboratory at the University of Washington (APL-UW) is planning to conduct a basic research experiment to explore the range and frequency dependence of the characteristics of long-range sound propagation, including bottom interactions, temporal and vertical coherence, and the competing effects of scattering and diffraction. In addition, the research experiment would provide tomographic data from which a temperature snapshot of the North Pacific could be estimated. This proposed experiment would take place approximately 1575 kilometers (km) (850 nautical miles (nm)) north of the Hawaiian Islands along a transect from 34 N/138 W to 35 N/173 W, and at a final station approximately 33 km (18 nm) north of the island of Kauai, Hawaii at 23 N/159 W. Beginning in fall 2004, a ship-suspended acoustic source would be used to transmit low-frequency signals at seven stations along the transect line and at one station off Kauai. In addition, four Ocean Bottom Seismometers (OBS) would be deployed at approximately N/ W to measure low and ultra-low frequency acoustic propagation in deep-ocean acoustic shadow zones close to the seafloor. Funding for this experiment was provided through grants from the Office of Naval Research. Based on scientific analysis in this Acoustic Analysis, there is no potential for significant harm to the environment from LOAPEX and the preparation of an overseas environmental assessment or an overseas environmental impact statement on the proposed action is not required. The acoustic source proposed for this experiment would have no effect on endangered or threatened species; hence, consultation with National Marine Fisheries Service regarding the Endangered Species Act is not required. No takes of marine mammals would occur from the proposed acoustic source transmissions during the experiment; hence, no authorization under the Marine Mammal Protection Act is sought. No effects on the environment, including the quality and/or quantity of essential fish habitats, would result from the acoustic source transmissions proposed for this experiment; hence, consultation with National Marine Fisheries Service under the Magnuson-Stevens Fisheries Conservation and Management Act is not required. 32

36 Appendix 8. LOAPEX Watch Schedule Three crews will stand 2 watches per day, 4 hr on and 8 hr off. Watch standers will come 15 min beforehand for handover. Cabin/bunk assignments are indicated; everyone has a single , Bruce Howe Watch Leader Rex Andrew Patricia Chang , John Colosi Watch Leader Mike Wolfson Garth Englehorn Chuck Fletcher , Jim Mercer Watch Leader Jinshan Xu Fred Karig Lyle Gullings 33

37 Appendix 9. Security at Snug Harbor UNIVERSITY OF HAWAI'I MARINE CENTER #1 Sand Island Access Rd. Pier 45 Honolulu, Hawaii Toll Free#: T /F July 2004 TO: All Vendors, Tenant Activities, and Other Authorized Personnel Using the Marine Center FROM: U.H. Marine Center Facility Security Officer SUBJECT: Security at the U.H. Marine Center Facility As of 01 July 2004, Homeland Security has mandated compliance with approved facility security plans at all facilities that have been required to provide security under their guidelines. The University of Hawaii is one of those facilities. In order to meet these requirements, specific rules must be put into place. This is a very serious undertaking that will require changes in the way we conduct our daily business. We must have the cooperation of all personnel that utilize our facility in order to remain operational. The entire facility is considered a restricted area accessible only to authorized personnel. Authorized personnel are those that possess and use a valid electronic gate card issued by our office, persons that are logged in by our gate guards with a valid reason for entering, approved vendors that we have ordered products from, trucks delivering/picking up authorized containers, ships crews and personnel embarking/disembarking or conducting business with ships moored at our dock. The following signs are posted on our main gate or parameter fencing. Security Notice, boarding the vessel or entering this facility is deemed valid consent to screening or inspection. Failure to consent or submit to screening or inspection will result in denial or revocation of authorization to board or enter. Restricted Area authorized personnel only, unauthorized presence constitutes a breach of security. This facility is currently at MARSEC LEVEL (I), (II), or (III) security level. MARSEC LEVEL I: Minimum appropriate protective security measures shall be maintained at all times in accordance to the vessel or facility security plan. MARSEC LEVEL I corresponds to the Homeland Security Advisory System (Green, Blue, Yellow). Report transportation security incidents or suspicious people, objects or activities to: USCG National Response Center, This Facility is currently operating at MARSEC LEVEL II security level. MARSEC LEVEL II: Appropriate additional protective security measures shall be maintained for a period of time as a result of heightened risk of a transportation security incident. MARSEC LEVEL II corresponds to the Homeland Security Advisory System (Orange). This Facility is currently operating at MARSEC LEVEL III security level. MARSEC LEVEL III: Further specific protective security measures shall be maintained for a limited period of time when a transportation security incident is probable or imminent, although it may not be possible to identify the specific target. MARSEC LEVEL III corresponds to the Homeland Security Advisory System (Red). All vehicles and personnel that wish to enter the facility are subject to random screening by our security guards in accordance with the facility security plan. Vendors with closed bed trucks delivering stores will be inspected at the gate prior to entry. Vendors that have valid gate cards may be subject to random checks. Trucks delivering containers must have a manifest for delivery to the Marine Center and should notify our office prior to delivery. Empty containers must be picked up soon as possible unless arrangements are made to store them at the facility. Personnel using gate cards must use them to enter and exit the facility. You cannot follow another vehicle through the gate without using the card reader. If caught, you will receive one warning after which you will lose gate card privileges. Not stopping for the gate guard is a serious breach of security and could jeopardize access privileges to the facility. Report any security problems to Bob Hayes, In the event of transportation security incident that results in an elevated MARSEC level at the facility, isolation or evacuation from a given area may be required. This will be directed by the facility security officer and may require stoppage of any loading/offloading operations and or evacuation of vehicles or personnel from the facility. The main gate is the only exit available for vehicle traffic during an evacuation. Any alternate route will be directed by the facility security office. 34