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- First measure the sea surface temperature (SST) in the following manner. Water is taken by
lowering a SST bucket with a thermometer attached to its inside into the surface
water. The line attached to the bucket is tied to the railing; then the bucket is lowered
slowly over the side (and gently swung forward if the ship is moving) with enough
clearance from the ship's hull. After a minute of equilibration1 , the bucket is hauled on
board, and in a place sheltered from direct sunlight the temperature is read (a
flashlight with magnifying glass is available for night-time sampling). Read to the
nearest 0.01°C, if possible, but at least to a resolution of 0.02°C. Double-check the reading for errors in
the whole degrees.
- Measure the dry and wet-bulb air temperature with the psychrometer. The wet-bulb
temperature is obtained by wetting the bulb of the "wet" thermometer with a few
drops of distilled water. Turn on the psychrometer motor and take the psychrometer
outside the bridge. Make sure psychrometer observations are made over an upwind
railing, to avoid contamination from ship heating (heat radiated from the ship's hull).
Shield the thermometers from direct sunlight while taking the reading. Double-check
your measurement if the air temperature is higher than the SST, move to a lower
deck protected from the sunlight if necessary.
- Wind speed and direction should be taken from the unobstructed anemometer
located on a tall pole above the bridge. The data display for this anemometer is
located in the electronics room behind the bridge, on the top shelf of a rack
perpendicular to the bulkhead. Read the Ship's speed and heading immediately
after taking the wind observations.
- Take the Ship's Speed and Ship's Heading from the ADCP display in one of the
computers in the electronics room, the displayed readings are:
-
Ship's Speed (kt)
Course over ground Ship's Heading - Take the latitude and longitude from the display in the electronics room.
- The atmospheric pressure can be read directly from the barometer located in the Rock Lab. Before taking the measurement, tap gently on the center of the glass cover with your fingertips to stabilize the needle.
- Check the thermosalinograph time-series plots of temperature and salinity displayed
on the Matlab window in the Electronics Lab. Make sure that the values are within
expected range, and that the signals do not show noise, spikes or sudden jumps.
- Check the ADCP display. The readouts for "Ash-gyro", "n", and "now:" on top of the
screen should all be updating every second with values other than "---". Also the
readout labeled "dt" at the bottom of the screen should have two values (e.g. 1,0),
which should not be larger than 10 each.
- Check that the ADCP is operating in the correct mode. Bottom tracking mode should be enabled when the bottom depth is less than 500 m. Usually bottom tracking mode is enabled between Snug harbor and Kaena Point at the beginning and at the end of the cruise. During bottom tracking the ADCP screen displays a value for the bottom "DPTH" and values for the ship's velocity relative to the bottom (these values are large negative numbers when the bottom depth is beyond the signal's reach, about 500 m). When bottom tracking is disabled the values for "DPTH" and ship velocity should be empty fields.
- in the acquisition computer: D:\hot-* (* = cruise number)
- in the backup Zip disk: \hot-*, \hot-*\plot
- in the processing computer (follow instructions from the Protocols manual)
- Take thermosalinograph samples, check T and S traces on Steve Poulos's computer.
- Select bottle depths at 200 dbar intervals starting at 1000 dbar (add 4500 dbar, salinity minimum, oxygen minimum and near-surface [5 dbar]).
- Maximum depth should be about 10 m off the bottom, if possible. Log in the position at the maximum depth.
- Take salinity duplicates from each level.
- Make the following plots:
- G-1000 (give this plot to the JGOFS group)
- OXYTST
- OXY5000
- TS
- W-1000
- W-5000
- DTC5000 (5000 dbar difference plots) (can be selected at the end of the plotting program)
- Select bottle depths at constant density levels by filling up the density cast sheet. Select the rest of the 24 bottles including maximum and minimum S, O2, Fluorescence; and filling up gaps between levels.
- Make the following plots:
- G-1000 (give this plot to the JGOFS group)
- OXYTST
- TS
- W-1000
- DELTATC (1000 m TC difference) (can be selected at the end of the plotting program)
- Maximum depth
- Salinity minimum
- Salinity maximum (if any, otherwise Oxygen minimum)
- Mixed layer (5 dbar)
- Take meteorological observations every 4 hours at selected GMT hours (only at station ALOHA).
- Enter data in processing computer immediately after taking the observations (run METOBS), and plot the data in MATLAB (run METPLOT). Check the plots for errors in the data and repeat any measurement if necessary.
- Take thermosalinograph samples every 4 hours, check T and S traces on Steve Poulos's computer.
- Take thermosalinograph salinity samples every 4 hours throughout the cruise (preferably at the same time as the meteorological observations).
- Check the thermosalinograph Matlab plot (in S. Poulos's lab) after taking each salinity sample. Check for glitches or offsets in the temperature and salinity time series plots.
- Check that the current speed traces look within range (-0.5 to 0.5 m/s in the upper 200-300 m).
- Check that the navigation information is present on the ADCP display.
- Work vests: All personnel are required to wear a work vest. Work vests are provided by the KOK Ka'Imikai-O-Kanaloa.
- Covered shoes: All personnel are required to wear covered shoes.
- 4 ea. Cargo straps: 1" webbing with stainless steel ratchets to tie down the rosette. These straps may be borrowed from the STAG's deck technician provided we return them promptly after the cruise.
- 2 ea. Pole hooks: A pole hook is a removable spring loadedspring-loaded clip mounted at the end of a pole. A tag line is secured to the clip. The pole hook is used to attach the tag line to the rosette package. The pole is disengaged from the clip once the clip is attached to the rosette. The pole hooks are to be stowed, during the cruise, in their respective clips (to be installed prior to each cruise) in the air castle.
- 1 ea. Happy hooker. Auxiliary spare if a pole hook is lost or damaged.
- 1 ea. boat hook: secured in forward set of clips.
- 2 ea. Tag lines: each: each line is 35 feet in length. The end of each line is fastened to the deck.
- 1 ea. Tag line, 40 feet in length is needed for rough weather conditions. This line shall be readily available in the air castle.
- 4 ea. Cleats: The cleats are hash marked to identify their respective location.
The Ka'Imikai-O-Kanaloa crew is responsible for the installation and maintenance of the cleats.
- The two outboard cleats are aligned such that the outboard horns are toed 15 to 30 degrees away from each other.
- The two inboard cleats are aligned such that the horns are positioned athwartships.
- Yellow tape: The winch cable is flagged eight inches above the termination with
yellow tape as a gauge for the Deck Leader and the Winch Operator to help keep the rosette package from being lifting too
high off the deck.
The Winch Operator is to keep the yellow band below the upper deck. The risk of damaging the mechanical termination is greatly increased when the rosette package is lifted higher than twelve inches above the deck. The mechanical termination can be damaged by being wrapped over the sheave or by hanging up on the sheaves' cheeks.
An alternative guide for the winch operator would be to keep the base of the rosette package within six inches of the deck.
- Forward Tag Line Person
- Set up the forward tag line through the rosette fairlead and the forward cleat.
- Man the forward tag line during the launch process and recovery process.
- Secure the rosette frame to the deck after recovery is complete.
- Flake the tag line neatly on deck.
- Aft Tag Line Person
- Set up the aft tag line through the rosette fairlead and the aft cleat.
- Man the aft tag line during the launch / recovery process.
- Secure the rosette frame to the deck after recovery is complete.
- Flake tag line neatly on deck.
- Deck Leader
- Responsible for directing the launch and recovery operations on deck. Once the package is in the water, control is passed to the Lab console operator.
- Ensure the safety net is removed prior to launch or recovery and that it is reinstalled promptly thereafter.
- If additional light is required:
- Turn on Breaker #17 on panel #LP102 which is the second lower left breaker on the panel directly in front of you as you exit the stairwell on the 01 deck.
- Turn on the 500 W floodlight overhead and aft of the CTD. The switch is located overhead, just inboard of the light.
- Ensure that the CTD is tied down immediately after recovery.
- In rough weather, assist the forward tag line person to hook onto the rosette.
- Winch Operator
- Operation of the winch and boom.
- Communications with the Lab and the Bridge via the Clear Comm system.
- Verify permission to launch or recover.
- Relays communications between the Deck Leader and the Lab via the Clear Comm
system.
- Informs the Deck LeaderLab of launch status and progress.
- Lab (Lab Console Operator)
- Operates CTD console and computers
- Directs the cast from the Lab while the rosette package is in the water.
- Communicates with the Winch Operator and with the Bridge via the Clear Comm system.
- WOCE Group Person
- Turn pinger on for the deep casts; turn pinger off after recovery
- Thorougthly flush the CTD plumbing with Triton X solution upon recovery, remove for deployment
- Final checkout of rosette prior to deployment
- Third Tag Line Person: (discretionary)
- Assist the aft tag line person to hook onto the rosette during recovery.
Note: All personnel must learn and use standard hand signals (refer to appendix)
4.1 Meteorological observations
4.1.1 Data measurements
Every 4 hours, at 00:00, 4:00, 8:00, 12:00, 16:00, and 20:00 hours (GMT, 10 hours ahead of Hawaiian time) meteorological observations are conducted and logged (see Appendix A for sample log sheet). Using information displayed on the ship's navigational computer display (in the Electronics lab), record the ship's position (GPS), speed through the water, heading, (apparent) wind direction and speed (from the upwind side of the ship if more than one anemometer reading is available), atmospheric pressure, dry- and wet-bulb air temperature using our psychrometer, sea surface temperature, cloud type, cloud amount and associated weather code (see Meteorological Observations Binder).Use the following procedures when taking meteorological observations on the R/V Ka'Imikai-O-Kanaloa:
4.1.2 Data entry and plotting
The meteorological observations should be entered and plotted in the processing computer immediately after taking the measurements. The data entry program performs some error checking that together with the data plots should help to identify suspicious measurements. These suspicious data will need to be measured again immediately.On the processing computer, run program METOBS.EXE (located in the D:\METOBS subdirectory, double-click on the "METOBS" icon) and enter the information from the meteorological observation log sheet as indicated by the program. Double-check your entries before exiting the program. Upon exiting, files MET.DAT, MET1.DAT and MET2.DAT will be updated (they contain identical information, just in different formats).
Open the MATLAB window (double-click on the "MATLAB 5.3" icon), and run the
METPLOT program. The program will read and plot time series of the data from the
MET1.DAT file. These plots are useful to identify errors in the data when compared
against data taken previously during the cruise.
However, there are some simple checks everyone can make to be sure that the ADCP
is running properly. In the upper right-hand corner of the ADCP display, there is
an "Ash-gyro" readout. This readout displays numbers corresponding to the heading
information which is being fed in by the GPS. Occasionally, the transmission of
GPS data into the ADCP fails. When this happens, dashed lines '---' will appear
in the "Ash-gyro" readout rather than numbers. An electronic buzzer may also
sound if the GPS data transmission fails. To the right of the "Ash-gyro" readout
is a readout titled "n" . This displays the number of GPS samples which have been
obtained in the past 5 minutes. If ever dashed lines'---' are seen in either the
"Ash-gyro" or "n" readout displays, either the ship's or the WOCE electronics
technician should be informed immediately so the GPS communication can be
reestablished.
On the bottom right of the ADCP display, there is a readout labeled "dt". There
are two numbers to the right of "dt". These numbers track the differences in the
ADCP PC's time and the GPS fix time in integer number of seconds. The numbers are
usually small (the display usually shows 0 or 1). If either of the numbers become
very large (more than 10), the ship's or the WOCE electronics technician should
be informed as this would be an indication that there is a problem with either
the PC or GPS time base.
These simple checks of the ADCP monitor should be made about every hour to make
sure that the GPS as well as the ADCP computer are running properly.
On some cruises a self-contained ADCP unit is being lowered simultaneously with
the CTD. Again, maintenance of successful operations with this equipment is the
responsibility of an experienced operator.
The thermosalinograph readings are displayed in the Electronics lab aboard
the ship. When taking Meteorological Observations (see Section 4.1), the performance of the thermosalinograph
should also be monitored. A gross error check can be made just by looking
at the thermosalinograph's temperature and salinity display, and at
the computer displaying time-series of temperature, conductivity and
salinity. For a typical HOT cruise, we expect temperatures between 22
and 28 °C and salinities between 33 and 36 psu. If it is observed
that either the temperature or salinity readings exceed these ranges,
the ship's or the WOCE electronics technician should be notified immediately
as readings outside of these ranges would most likely be due to a problem
with the system.
In the R/V Ka'Imikai-O-Kanaloa the thermosalinograph samples are collected from a pipe located near the bow of the ship. Access this area by going through the engine room entrance below the main deck, forward of the galley. A spigot dispensing water from the surface seawater system drains into a bucket that is emptied on demand by an internal pump. The water from this spigot passes through the thermosalinograph sensors from a distance of about 2 m.
An important element in thermosalinograph bottle sampling is the digital clock used to record the time of the sampling. At the beginning of the cruise, one of the WOCE console
operators will make sure that this clock is accurate to the second with the GPS GMT
time. It is important to know exactly when the bottle sample is taken so it can be matched with the thermosalinograph data. By pressing the "mode"
button on the clock, the display can be changed from hour/minute
to seconds.
Thermosalinograph bottle samples are taken every 4 hours in conjunction with
Meteorological Observation times (00:00, 04:00, 08:00, 12:00, 16:00, 20:00 GMT - see Section 4.1) throughout the entire cruise. There is a
thermosalinograph log sheet on which, the bottle serial number, date and time of
sample can be recorded. There are also thermosalinogaph bottle labels on which
date, time of sample, sea surface temperature (SST) and sea surface salinity
(SSS) are recorded.
To start sampling, take the thermosalinograph log sheet, the digital clock and a sampling bottle to
the sampling room. Open the surface seawater faucet to full speed. Take note
of the time when you open the faucet. In the R/V Ka'Imikai-O-Kanaloa it is not necessary to let the water run for more than 10 seconds because the sensors are very close to the faucet. Glass bottles are used for the thermosalinograph
samples, and the procedure to take these samples should be the same used when sampling
from the CTD Niskin bottles (see Section 3.1.7). After rinsing the bottle three times, take
the sample and mark down on the thermosalinograph log sheet the exact time (hour:minute:second) the sample was taken.
Next proceed to complete and attach the label on the sample bottle. Record on the label
and on the log sheet the date and exact time (to the second) that the sample was taken.
Record also the sea surface temperature (SST) and sea surface salinity (SSS). These
readings can be obtained in the Electronics lab. While obtaining the readings, make sure
they are in the correct range, 22-28 °C for temperature and 33-36 psu for salinity. After this,
the bottle may be returned to its box, "right-side-up".
[____] [____] [____] [____] [____] [____] [____] [____] [____] [____] [____] [____] [____] [____] [____] [____] [____] [____] [____] [____]
Deep and shallow WOCE casts must be taken back-to-back, preferably early in the cruise. Both casts must
have 24 bottles fired at levels selected by the PO group, with samples of salinity, oxygen and nutrients. The
casts should start at the center of the station.
Every CTD cast must be processed immediately after the end of the cast, and the PO
watch leader must check the "tcdiff" plots on the processing computer, and the
diagnostic plots.
Open casts should have at least 4 bottles for salinity samples at the following levels:
[____]
The deployment and recovery of the CTD rosette package is one of our most hazardous
procedures; therefore, all necessary precautions shall be implemented to ensure the safety of
personnel and equipment.
In rough or heavy seas, an additional tag person may be necessary for recovery. The requirement for an
additional tag person is discretionary based on the prevailing conditions; however, should there be any
doubt from any member of the launch or recovery crew as to the capabilities to perform operations safely
with the usual three person team, a fourth person (Third Tag Person) shall be required.
The following list is a summary of the personnel and their responsibilities.
4.2 XBT sampling
Occasionally, XBTs (Type 7) are launched during cruises. The XBT launcher remains
on deck and is connected to the Bathy Systems deck unit in the E-lab by a cable.
Before a launch, turn the deck unit POWER on, then have an on-deck operator load
a T-7 probe into the launcher. Press the RESET switch on the deck unit panel, and
determine the ship's position. On the computer, go to D:\xbt, run program xbt.exe in a MS DOS window, and complete dialogue by entering required information concerning concerning XBT-type, ship's
name, cruise and drop numbers, latitude degrees, minutes and seconds (separated
by commas), hemisphere (repeat for longitude). Depth-temperature coordinate axes
will then appear on the screen as well as the message 'READY TO LAUNCH'.
Communicate to on-deck operator to launch the probe. A successful launch will
produce a real-time temperature-depth profile on the screen (0 to 700 m). Data
are stored in files whose names consist of digits that reflect the type of XBT,
drop number and series of the drops, e.g. D:\71A (no file-type extension).
4.3 ADCP operation
After the shipboard ADCP system has been booted up and is displaying vertical
profiles of horizontal current components (relative to the ship), and while the
water depth is less than 500 m, bottom-track calibration for the ADCP should be
enabled. As the operation of the ADCP requires some experience, it is recommended
that modifications such as initializing bottom-tracking mode or changing the
logging frequency, should remain the responsibility of the WOCE electronics
technician and the marine technician trained in the control of the ADCP system
(refer to the RD Instruments Manual for more information).
4.4 Thermosalinograph operation
The thermosalinograph is an instrument system that obtains a
continuous record of sea surface temperature and salinity. An intake at the bow
of the ship collects water at some distance below the sea surface (3 m in the R/V Ka'Imikai-O-Kanaloa). A
continuous flow is pumped through the ship's surface seawater system passing through the
thermosalinograph sensors, which measure temperature and conductivity samples every 10 seconds
to provide a temperature and salinity time-series.
4.5 Thermosalinograph Bottle Samples
In order to calibrate the thermosalinograph conductivity/salinity readings,
bottle salinity samples must be collected in much the same way as bottle salinity
samples are collected from Niskin bottles for the CTD (see Section 3.1.7).
4.6 Supplements
4.6.1 Regular check of continuous sampling instruments
The thermosalinograph and the ADCP should be running continuously during the cruise.
Regular checks of these systems should be performed at least every 4 hours (every 1 hour
is desirable), at the time of the thermosalinograph bottle salinity sampling. Any problems
with these systems should be immediately communicated to the STAG's electronics
technician.
4.6.2 HOT cruise check list
The following list is a summary of some of the procedures to be conducted before and
during cruises, and it should be completed by WOCE cruise personnel during every
cruise.
HOT-_____ Cruise Check List
Boxes must be initialed
Pre-Cruise
Loading Day, at Snug harbor
First Cruise day
At Station Kahe (Station 1)
In transit to ALOHA station
At Station ALOHA (Station 2)
CTD casts
Deep WOCE cast (1020 dbar)
Shallow WOCE cast (1020 dbar)
Other shallow casts
The rest of the shallow casts should reach at least 1020 dbar, and should be conducted at 3 hr intervals for
the 36 hr period (the shallow WOCE cast could be one of these casts). Salinity must be sampled from
every bottle fired.
The rest of the shallow casts should also include bottles at these levels, which often coincide with the levels
selected by the JGOFS group.
The plots should be the same as those for the shallow WOCE cast.
Second deep cast
The second deep cast should start at the center of the station and go to a maximum depth of about 10 m off
the bottom whenever possible. Log in the position at the maximum depth. Bottles for salinity sampling
should be at approximately 1000 dbar intervals below 1000 dbar, in addition to the levels selected for open
casts. At least 8 of the bottles should be sampled for dissolved oxygen (maximum depth, 4000, 3000, 2000
dbar, oxygen minimum, salinity minimum, oxygen (or salinity) maximum and mixed layer).
Meteorological observations
At Station HALE-ALOHA (Station 8)
A shallow cast to 1020 dbar should be conducted at this station. At least 8 bottles should be fired for salinity
and oxygen sampling. Oxygen samples should include the maximum depth, oxygen minimum, salinity
minimum, oxygen maximum and near-surface.
At Station Kaena (Station 6)
A near-bottom cast should be conducted at this station (~2500 dbar). Bottles at 1500 and 2000 dbar should be
fired for salinity sampling, in addition to the levels selected for open casts.
In transit to Snug harbor
Thermosalinograph
ADCP
4.6.3 HOT CTD Deployment / Recovery Procedures aboard R/V Ka'Imikai-O-
Kanaloa
Purpose
Define routine procedures to safely deploy and recover the CTD rosette package on the
R/V Ka'Imikai O Kanaloa Ka'Imikai-O-Kanaloa(KOK).
Tools and Supplies:
Personnel and their Responsibilities:
Three deck personnel from the scientific party (Deck Leader, Forward Tag Line Person, and Aft Tag Line
Person) are required to launch and / or recover the CTD with at least one of the personnel being
from the WOCE group.
Pre- Launch Procedure:
- Lab to notify Bridge of the following:
- Scheduled deployment time at least 15 minutes in advance.
- Desired location to position the ship.
- Request Winch Operator.
- WOCE Personnel
- Remove Triton X wash bottle.
- Turn on pinger if it is a deep cast.
- Check for removal / installation of fluorometer. If the fluorometer is removed, ensure the high-pressure dummy plug is installed on the CTD.
- Check for loose gear, cables, etc. on the rosette.
- Deck Leader
- Turn on lights if necessary.
- Verify recovery area is clear of all loose and extraneous gear.
- Stage boat hook for easy access should it be necessary to use it.
- Remove safety netting; stow forward out of the way by hooking it on the railing cleat.
- Tag Line Personnel
- Remove tie downs.
- Stage tag lines through the rosette's fairleads (see diagram).
Launch Procedure:
-
The Deck Leader takes up the wire and puts tension on it by
pulling horizontally on the termination. The Deck Leader then signals to the Winch Operator to
take up the slack in the wire. When the Deck Leader releases the termination from his grip, it is a
signal for the Winch Operator to stop.
All hands stand by for launch clearance from the Bridge and from the Lab. When the Winch Operator receives the all-clear from the Lab and the Bridge, he then informs the Deck Leader that the deployment may begin.
The Deck Leader verifies that the launch crew is ready. When ready, the Deck Leader signals to the Winch Operator to begin deployment.
The Winch Operator deploys the CTD package by moving the boom out. The initial extension of the boom lifts the package from the deck and moves it outboard. This requires some skill in manipulating the boom and the winch simultaneously. From the Winch Operator's perspective, launching and recovery is easier if the operation can be accomplished without stopping. This is a situation dependent on sea state conditions where coordination and timing are required to adjust the winch and boom controls. Once the rate of the boom or winch is fixed, the operator can then adjust the other axis (winch or boom) for a smooth, continuous, operation.
The Winch Operator must be careful to keep the bottom of the package within 6 inches of the deck to protect the mechanical termination from damage. It is the Deck Leader's responsibility to observe and guide the Winch Operator. If the CTD package is lifted too high off the deck the termination can be pulled over the sheave or the cable grip may be pried off the cable by getting caught on the cheeks of the sheave, thus weakening the mechanical termination.
While the package is being deployed, the tag lines are kept somewhat taught, depending on the situation and sea state. The rosette package should be somewhat restrained such that the package leans outboard due to the tag lines keeping tension while the boom is being deployed. Once the boom is fully deployed, the bitter end of the tag lines should be allowed to be paid out, retaining some tension on the line, until the bitter end is reached. The bitter end is then allowed to free fall into the sea, clear of the rosette package. The tag line is then retrieved while the package continues to be lowered into sea. Due to the high freeboard from where the CTD is launched, it is important to minimize the time the package is in the air where the package may gain momentum to swing and perhaps hit the ship's hull.
It is important to note that the bitter end of the tag lines should be deployed clear of the rosette package in such a mannner as to prevent the lines from getting tangled with each other, getting caught in the rosette package, or coming into contact with the sensors.
The Deck Leader informs the Winch Operator when the package is in the water. The Winch Operator then continues deployment of the package to a depth of 10 decibars to prime the CTD plumbing. Meanwhile, the Deck Leader secures the safety net and the Tag Line Personnel neatly flake the tag lines on deck in preparation for the recovery.
The CTD package remains at 10 decibars until the pumps turn on and prime the plumbing system. When the Lab's Console Operator is satisfied that the CTD system is ready and operating correctly, the Lab will inform the Winch Operator to bring the package to the surface to begin the down-cast.
The Winch Operator, upon confirmation from the Lab, will bring the package to the surface at a maximum rate of 20 meters per minute. Since the Winch Operator cannot see the package at the surface, the Deck Leader watches the package and surrounding seas to determine the optimum point at which to stop the package at the surface. When the Deck Leader signals to the Winch Operator that the package is at the surface, the Winch Operator should immediately deploy the package to its target depth.
Our objective is to bring the package's instruments as close to the surface while minimizing the time at the surface where the possibility of losing the plumbing's priming may occur due to swells or rolling of the ship.
Pre-Recovery Procedure:
- Deck Leader: (To be accomplished well before the CTD is at the surface)
- Notify team members to assemble on deck for recovery.
- Remove safety netting; stow forward out of the way by hooking it on the railing cleat.
- Turn on lights if necessary.
- Verify recovery area is clear of all loose and extraneous gear.
- Tag Line Personnel
- Stage pole hooks.
- Stage tag lines for retrieval by flaking the lines neatly on deck.
- Lab
- Notify the Deck Leader and the Winch Operator when ready to recover the CTD.
- Winch Operator
- Request clearance from the Bridge to recover the CTD.
- Third Tag Line Person (discretionary during rough weather)
- Man the pole hook, working as a team with the Aft Tag Line Person.
- Leave the recovery area, with the pole, once the hook is secured to the rosette.
- The Aft Tag Line Person, in this case, will focus on tensioning the tag line.
Recovery Procedure:
Towards the end of the CTD cast, the Lab Operator notifies the Deck Leader to prepare for the recovery of the CTD. The Deck Leader notifies other team members to assemble on deck for recovery. If lights are necessary, they are to be turned on at this time. The Deck leader also ensures that the recovery area is clear of all loose and extraneous items. The Deck Leader then prepares for the recovery by removing the safety net. All hands stand by to wait for clearance from the Bridge and from the Lab.When the Winch Operator receives the all clear from the Lab and the Bridge, he then informs the Deck Leader that the recovery may begin.The Deck Leader verifies that the recovery crew is ready. When ready, the Deck Leader signals to the Winch Operator to begin the recovery. The Deck Leader directs the Winch Operator to hoist the rosette package out of the water until the end of the cable grip termination is about twelve inches from the cheeks of the sheave (marked with yellow tape).
The Winch Operator then retracts the boom and takes up on the winch to keep the package at the same elevation. This is the most difficult maneuver for the Winch Operator because he must keep the rosette package steadily positioned by the simultaneous operation of two controls. Therefore, once the rate of motion of the boom is fixed, the winch is adjusted for smooth continuous motion.
As the rosette package is brought close enough to the ship for the tag line personnel to attach their pole hooks, the Deck Leader will signal to the Winch Operator to STOP all motion of the boom and the winch. At which time, the pole hooks are attached to opposite fairleads on the base of the rosette frame. The poles are then set on deck (or secured in their holders) and a turn is taken around the respective inboard cleat and tensioned evenly. Once the tag line personnel are in position, the Deck Leader will signal to the Winch Operator to continue retracting the boom to complete the recovery process. The Tag Line Personnel must coordinate their tensioning together with the Winch Operator.
The Winch Operator will completely retract the boom and then set the rosette package on the deck while the Deck Leader is pulling the package slightly inboard to allow extra clearance for sampling.
Note: The rosette package shall be allowed to rest on deck in its natural orientation. Spinning or turning of the rosette package (e.g., for convenience of sampling) will cause undue stresses on the cable and termination due to the extremely short scope of the cable.
The Deck Leader will ensure that there is a slight amount of slack in the winch cable. The Winch Operator then secures the boom and winch hydraulic systems.
While the Tag Line Personnel are securing the rosette package to the deck, the Deck Leader is securing the safety net.
The WOCE person then flushes the CTD sensors with TRITON X solution and turns off the pinger if it was on. He or she should also inspect the CTD / rosette package for any signs of problems and record those in the science log.
The recovery operation is complete when the boat hook, pole hooks, and work vests are stowed, the rosette package is secured to the deck, and the tag lines are neatly flaked on deck in preparation for the next deployment.
In rough weather, the procedures will remain the same with the exception of a discretionary Third Tag Line Person who will assist the Aft Tag Line Person to hook onto the rosette. The Third Tag Line Person and the Aft Tag Line Person are to work as a team where one person mans the pole and hooks onto the rosette, then moves away (with the pole) from the recovery area, the other person mans the tag line, keeping tension as in a normal recovery.
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