R/V Revelle, Alford Cruise Cruise Plan, 6/1/2010

Transcription

1 R/V Revelle, Alford Cruise Cruise Plan, 6/1/2010 Overview The following is the cruise plan for the Internal Waves in Straits Experiment (IWISE) pilot leg (27 at-sea days) of the IWISE/ITOP projects. Our goal is to understand internal waves in straits, so we will be working between Taiwan and the Philippines (Figure 1). Our general plan is to deploy profiling moorings for the duration of the cruise, and to work around them with a series of 36-hour-long yo-yo CTD/lowered ADCP stations while they profile. Taiwanese and Philippines clearances are pending. Figure 1: Broad view of our work area. Colors represent generation of semidiurnal internal tides; arrows represent their energy flux. Moorings and CTD/lowered ADCP stations are shown. The location of PIES 5 is (20.5N, 119E) - slightly west of the map domain. We plan to deploy a total of nine moorings at the locations shown, of which five (PIES 1-5) will be 1

2 recovered at a later date by another ship. The other moorings will be recovered at the end of our cruise. Between the deployment and the recovery, we ll conduct 36-hour yo-yo CTD stations while holding station or drifting slowly at about 15 locations, some of which are shown with purple squares. Others will be determined during the cruise. Station locations are given in Table 1. See Table 2 for a strawman timeline. Our cruise is part of a larger block of time shared by the joint IWISE program (this cruise) and the ITOP Typhoons program. If a strong typhoon comes along after Aug 20, we will return to port to allow the ITOP group to conduct a three-week survey of the typhoon wake and then collect instruments (a total of days), in which case we would return afterwards to conduct the balance of our cruise. In that event, we would likely leave the moored assets in the water during that period and recover them in the second portion of our cruise. Table 1: IWISE Stations. Note all positions are approximate, and given in decimal degrees. After deployment, please maintain 0.25 nm radius from MP-N and MP-S. Station Lat, Lon Depth Comments MP-N 20.6N, 121.3E 3663 m 135 nm to KS (13.5 h) MP-S 19.85N, E 3652 m 169 nm to KS (17 h); 61 nm to MP-N (6 h) A N, E 1200 m P N,121.30E 3679 m P N, E 3630 m P N, E 3560 m P N, E 3262 m P N, E 2730 m P N, 120.6E CTD N, 120.8E CTD stations locations nominal CTD N, 121E CTD N, 121.5E CTD N, 121.2E CTD N, 121.4E CTD N, 121.6E Loadout Timing We plan to begin loadout as soon as Graber s cruise returns. He is scheduled to return August 12, but has stated that if all goes well he would return 8-10 days early (weather dependent). We are semiconservatively assuming he will return 7 days early (Aug 5), in which case we would begin loading August 6-7. We plan to purchase air tickets leaving August 4 and arriving August 5, to be ready for loading August 6. In the week before this, we can monitor his progress, and delay our flights if needed. We plan on two days of loading (for an August 8 departure). If we leave on this date, our return date would be September 3. 2

3 To minimize overall mob and demob time, loadout will be shared between our cruise and the two subsequent ITOP cruises. Hence, we will load gear for our own cruise as well as the Rockland scientific profiler and underway CTD to be used by the ITOP group. It is possible we will also use these instruments a bit during our cruise, as described below. In addition, ITOP gliders will be loaded, but not used during our cruise. Deck Plan The deck plan is shown in Figure 2. We plan to situate the microstructure and underway CTD systems to port and starboard aft quarters, respectively. For the mooring operations, the mooring wire will be run from the SIO TSE mooring winch though a rig-up block hanging from the A-frame. The mooring winch will be situated centerline. We will bring a wire spooler, which requires 3-phase 220V AC power, to load and unload wire to/from the mooring winch. We will use this through a rig-up block hung from the A-frame to starboard of the trawl block. We like to use an air tugger mounted on the A-frame stanchion to operate a flying block hanging from the rig-up block. We plan to use the trawl wire to deploy the anchors, and either the trawl wire or the the port kunckleboom crane to launch the floats at the start of each profiling mooring deployment. Floats will be staged along the port rail, while anchors will be placed inboard of the port A-frame stanchion. Please refer to the overboarding plan for the moorings, given in a separate document, for deck and rigging details. The two 20 vans on the main deck will house glass floats for our moorings and deck storage. Near the end of our cruise we will attempt to fully load our gear into them, allowing for a quick turnaround between our cruise and the next. A third 20 van with the Lee gliders will be stored on the O1 deck during our cruise, and moved to the main deck for their cruises. If conditions permit and time allows, we will attempt to move all of our gear into the vans prior to the end of our cruise. Then, dockside after our cruise, our two vans will be offloaded and the Lee van re-situated on the main deck. Gear Profiling moorings We will deploy two profiling moorings in about 3500 m of water (Figure 1, stars), which consist of a crawler making repeated traverses of a taut vertical wire with two subsurface floats (one steel, one syntactic foam) for flotation. These are anchor last deployments. The detailed overboarding plan for these moorings was given to the restech in a separate document. Mooring diagrams for each are given in Figures 3 and 4. Inverted Echo Sounder with Pressure (PIES) moorings Six PIES moorings (Figure 5 will be deployed at the locations shown (Figure 1, red circles). These are very simple deployments. We will simply lower them over the side to the waterline and release them with a mechanical release. They then sink to the bottom, which takes about an hour. PIES moorings P1-5 will be deployed on our cruise, and recovered on another cruise. P6 will be deployed and recovered on our cruise. Pending approval of its owners, P1 will be deployed at A1 for the duration of our cruise, and then recovered, reprogrammed and redeployed at P-1. 3

4 PIES STANDS Microstructure winch FLOATS 20-ft container 20-ft container ANCHORS spooler TSE mooring winch Underway CTD air tugger on a-frame Mooring Gear Box SPOOLS + CAGES wire wire cage cage cage Figure 2: Deck plan. For these and all our acoustic commands sent to range on and release the moorings, we will bring pigtails that allow us to drive the ship s 12-KHz transducer with our decksets. This has worked well for us in the past. Acoustic Doppler Current Profiler (ADCP) mooring Mooring A-1 is a short mooring consisting of an ADCP housed in a syntactic sphere about 20 m above the bottom. The mooring will also be deployed anchor last in about 1200 m of water (Figure 1, yellow circle). The mooring diagram is given in Figure 6. As noted above, the PIES for P-1 will be deployed several hundred meters from A-1 during our cruise. CTD/lowered ADCP stations Between the mooring deployments and recoveries we plan to conduct about hour time series at the stations shown in Figure 1, as well as others to be determined based on the results of these initial ones. We may try to hold station for some of these, but we expect very strong currents (strong tides and the Kuroshio current system) and so may find better wire angles by drifting slowly. 4

5 The CTD will be fitted with a lowered ADCP system. We plan on using the ship s brackets (the restech is already aware of this) and upward and downward 300-KHz workhorse ADCP s and a battery pack to the CTD frame. We will also possibly attach a vane to allow special microstructure sensors on the package to face the flow past the cage. Jonathan Nash is discussing this with the restech. Rockland Scientific microstructure profiler This is a loosely tethered instrument typically deployed from the stern with a small winch while steaming slowly (1-2 knot). We may substitute this instrument for some of the CTD/LADCP profiles. It consists of a hydraulic winch (700 lbs; 32 x 40 ). This will be run off its own hydraulic power pack (30 x 34, 220 lbs). The system requires 208VAC, 3 phase. The profiler itself (100 lbs) is deployed from the stern with no line tension through a small line puller (24 x 24 ), and recovered via the A-frame. Initial loadout will involve simply staging the three boxes for the winch, powerpack and line puller out of the way on deck; if we use it during our cruise setup only requires 2-3 hours. Underway CTD The OceanScience underway CTD system is designed to be deployed behind the ship while steaming at 8-12 knots. It is primarily for use by the ITOP program. It will be setup and operated from the starboard aft quarter. Timeline Uncertainties in the departure date and the possibility of being interrupted make doing a timeline very difficult. In addition, we are tied to the phase of the tides which will ultimately determine which CTD stations will be done at which times. However, we will certainly want to deploy moorings MP-N, MP-S, PIES-6 and ADCP-1 as soon as possible, and pick them up as late as possible. One strawman schedule assuming we leave on August 8 and are not interrupted is given in Table 2. Table 2: Draft IWISE Timetable, assuming 28 at-sea days and no interruptions. All transit times are estimated assuming 10 kt. Day Time What Comments depart Kaohsiung, make for MP-N (135 nm; 13.5h) Take XBT as soon as deep water reached for Multibeam cal arrive MP-N Multibeam on; finalize site/depth, choose makeup pieces begin deployment should take 3-4 h; 5 hours allotted for first one complete deployment, steam to A-1 (27 nm; 2.5 h) Deploy A Complete A-1deployment, steam to P-6 4-hour transit Arrive P-6, deploy (1 hour) Depart for MP-S 4 hour transit Arrive MP-S Multibeam survey, finalize site/depth, choose makeup pieces Begin deployment, MP-S 6 hours allotted Complete MP-S deployment 2-24 LADCP/CTD stations 22 days hour stations. PIES 1-5 deployments at convenient times during CTD work recover MP-S release with plenty of light left; recover in evening finish; steam to MP-N (recover P-6 en route) recover MP-N finish; steam to A recover A begin 24-hour weather/contingency day leave MP-N for KS (13.5 h plus 2.5 h for tie-up, etc) arrive Kaohsiung 5

6 Tides Figure 8 shows tides during our cruise. Personnel Science party and affiliations are as follows listed in Table 3. Table 3: Science Personnel. Who Role Inst. Matthew Alford Chief Scientist APL/UW Andy Pickering Grad Student APL/UW Zoe Parsons Technician APL/UW Mike Carpenter Engineer APL/UW John Mickett Oceanographer APL/UW Jonathan Nash PI OSU Harper Simmons PI UAF John Pender Technician UAF Jen MacKinnon PI SIO Tamara Beitzel Grad Student SIO Mary Huey Computer Tech SIO Josh Manger Restech SIO 6

7 3596.0m Top of float (60m depth) IWISE MP-N Target: Actual: xx -xx.xxx'n xxx -xx.xxx'e Depth: 3656m Depth: m m m m m m m Event Log / Notes: m m m m m m 22.0m 16.5m 15.0m 13.4m 3.0m (1) 5/8" shackles (0.66kg) (1) 1/2 shackle (0.31kg) 1/2 Long link chain (1m; 2.26kg) (1) 5/8" shackle (0.66kg) (1) 5/8" shackles (.66kg) 3 ton swivel (3.32kg) MP stopper MP stopper (1) 1/2" shackle (.31kg) (1) 5/8 shackle (.66kg) (1) 5/8" shackle (.41kg) (1) 5/8" sling link (.66kg) (2) 1/2" shackle (.62kg) (1) 1/2" shackle (.31kg) (1) 5/8 shackle (.66kg) (1) 1/2 shackle (.31kg) (4) 1/2" shackle (1.24kg) (6) 1/2" shackle (1.86kg) (3) 5/8" shackle (1.98kg) (2) 3 links LL chain (1.4kg) Drop link chain (2.0kg) 5/8" shackle & 5" ring (1.41kg) 1/2 Long link chain (1.5m; 4.14kg) (1) 3/4" shackle (xkg) 3/4 dia. Nylon line (10m; 0.22kg) (1) 3/4" shackle (xkg) 1/2 Long link chain (2m; 5.52kg) (3) 5/8" shackle (1.98kg) (2) 3 links LL chain (1.4kg) wheel 48" Steel Float 585 kg buoyancy Chipod OSU shallow (Depth 69m; 1.0kg) SBE 37 MicroCat (Depth 73m; 2.3 kg) Start time: 5/16" 3x19 PP jacket wire rope (10m; 3.25kg) ARGOS Beacon O.M.L. model 265 / Flasher S ARGOS ID# ARGOS On Time: Flasher On Time: 45" Syntactic Foam Float 300 kg buoyancy (MA) ADCP model RDI 75Khz Long Ranger w/press. (Depth 76m) MP stopper (Depth 78m) 0.393" PP jacket cortland line (1509m; 46.9kg 1500m cut) (10) Benthos model V glass floats (25.4 kg buoy. ea.) mounted in pairs on ½" long link chain (1m; 2.76 kg) SBE39 Temp. ext. w/press.; Att. to rel. (Depth 3643m; 0.70 kg) Logging? Start time: Benthos model 865 double acoustic release (25 kg each) RX(khz): RX(khz): Pinging? Enable: Enable: Moored Profiler (s/n 103) w/chipod Profile Range: MP Set-up: MP Start Time/Date: Beep? ? Flash? ADCP model RDI 300Khz Workhorse w/press. (Depth 74m) Pinging? Cover? Line out: MP stopper (Depth 1585m) Chipod OSU deep (Depth 1596m; 1.0kg) SBE 37 MicroCat (Depth 1598m; 2.3 kg) Start time: 5/16" 3x19 PP jacket wire rope (20m; 5.38kg) ADCP model RDI 300Khz Workhorse w/press. (Depth 1606m) Pinging? Cover? 3/8" aramid line - Harper (1010m; 10.4kg 1000m cut length) DVS RDI deep (depth 2621m; 1.0kg) 5/16" 3x19 PP jacket wire rope (5m; 2.18kg) 3/8" aramid line - Harper (1010m; 10.7kg 1000m cut length) TX(khz): TX(khz): Release: Release: 1632 kg anchor plus Danforth (1420 kg in water) Start Deploy: Drop Anchor: Date: Time: Wind Dir / Spd: 7 Date: Time: Hdg / Spd: Figure 3: Mooring diagram for MP-N.

8 3539.0m Top of float (60m depth) IWISE MP-S Target: Actual: xx -xx.xxx'n xxx -xx.xxx'e Depth: 3600m Depth: m m m (1) 5/8" shackles (0.66kg) (1) 1/2 shackle (0.31kg) 1/2 Long link chain (2m; 5.52kg) (1) 5/8" shackle (0.66kg) 48" Steel Float 585 kg buoyancy SBE 37 MicroCat (Depth 67m; 2.3 kg) Start time: 5/16" 3x19 PP jacket wire rope (5m; 2.18kg) m m m m Event Log / Notes: m m m m m m 21.0m 16.5m 15.0m 13.4m 3.0m (1) 5/8" shackles (.66kg) 3 ton swivel (3.32kg) MP stopper MP stopper (4) 1/2" shackle (.31kg) (2) 1/2" shackle (.62kg) (1) 1/2" shackle (.31kg) (1) 5/8 shackle (.66kg) (1) 1/2 shackle (.31kg) (8) 1/2" shackle (2.48kg) (6) 1/2" shackle (1.86kg) (3) 5/8" shackle (1.98kg) (2) 3 links LL chain (1.4kg) Drop link chain (2.0kg) 5/8" shackle & 5" ring (1.41kg) 1/2 Long link chain (1.5m; 4.14kg) (1) 3/4" shackle (xkg) 3/4 dia. Nylon line (10m; 0.22kg) (1) 3/4" shackle (xkg) 1/2 Long link chain (2m; 5.52kg) (3) 5/8" shackle (1.98kg) (2) 3 links LL chain (1.41kg) wheel ARGOS Beacon O.M.L. model 265 / Flasher S ARGOS ID# ARGOS On Time: Flasher On Time: 45" Syntactic Foam Float 300 kg buoyancy (MA) MP stopper (Depth 74m) 0.393" PP jacket cortland line (1207m; 37.6kg 1200m cut) (10) Benthos model V glass floats (25.4 kg buoy. ea.) mounted in pairs on ½" long link chain (1m; 2.76 kg) Benthos model 865 double acoustic release (25 kg each) RX(khz): RX(khz): Enable: Enable: Moored Profiler (s/n 103) w/chipod Profile Range: MP Set-up: MP Start Time/Date: Beep? ? Flash? ADCP model RDI 300Khz Workhorse w/press. (Depth 70m) Pinging? Cover? ADCP model RDI 75Khz Long Ranger w/press. (Depth 72m) Line out: MP stopper (Depth m) (6) Benthos model V glass floats (25.4 kg buoy. ea.) mounted in pairs on ½" long link chain (1m; 2.76 kg) SBE 37 MicroCat (Depth 1284m; 2.3 kg) Start time: 3/8" aramid line - Harper (1010m; 10.4kg 1000m cut) DVS RDI deep (depth 2310m; 1.0kg) 5/16" 3x19 PP jacket wire rope (30m; 7.5kg) 3/8" aramid line - (1252m; 13.1kg 1240m cut length) [1000m + 100m + 100m (Harper) + 20m + 20m (PS)] SBE39 Temp. ext. w/press.; Att. to rel. (Depth 3588m; 0.70 kg) Logging? Start time: Pinging? ADCP model RDI 75Khz Long Ranger w/press. (Depth 1285m) Pinging? TX(khz): TX(khz): Release: Release: 1632 kg anchor plus Danforth (1420 kg in water) Start Deploy: Drop Anchor: Date: Time: Wind Dir / Spd: 8 Date: Time: Hdg / Spd: Figure 4: Mooring diagram for MP-S.

9 Figure 5: A PIES mooring ready for deployment. 9

10 IWISE JN LR1 MOORING Event Log / Notes: Target: xx -xx.xxx'n xxx -xx.xxx'e Depth:???m Actual: Depth: 45" Syntactic Foam Float 309 kg buoyancy (JN) ARGOS ID# Beep? ARGOS On Time: ? Flasher On Time: Flash? 12.0m Top of float (??m depth) ADCP model RDI 75Khz Long Ranger w/press. (Depth 573m) Pinging? 10.5m (2) 5/8" shackles 2 ton swivel (1) 5/8" shackle 8.5m 7.0m 1/2 Long link chain (2m) (3) 5/8" shackle (2) 3 links LL chain Drop link chain 5/8" shackle & 5" ring ORE Acoustic Release model 8242XS (28 kg each) Enable: Release: Disable: Int (khz): 11 Rep (khz): 12 Enable: Release: 1/2 Long link chain (3m) Disable: Int (khz): 11 Rep (khz): m 1/2 shackle 1/2 Long link chain (3m) 1.0m (3) 5/8" shackle (2) 3 links LL chain 3 wheel 1425 kg anchor plus Danforth (1218 kg in water) Start Deploy: Date: Time: Wind Dir / Spd: Drop Anchor: Date: Time: Hdg / Spd: Figure 6: Mooring diagram for A-1. 10

11 Figure 7: The underway CTD being operated at the stern Start End 40 TPXO Zonal Current Prediction /25 08/01 08/08 08/15 08/22 08/29 09/05 09/12 Date 2010 Figure 8: East-west velocity in cm/s predicted from TPXO6.2 during our cruise. 11