HOT-64: Chief Scientist Report

Chief Scientist: L. TUPAS

Loading: July 26, 1995 
Departed: July 28, 1995 at 0900 
Returned: August 2, 1995 at 0800 
Vessel: R/V Maurice Ewing 
Operator: Lamont Doherty Earth Observatory, Columbia University 
Chief Scientist: Dr. Louie Tupas 
Master: Captain Stan Ziegler 
Deck Operations: Mr. Joe Stennet 
Electronics Technician: Mr. Paul Osgaard 
Computer Technician: Mr. Bill Robinson 
 

1. 	PLANNED SCIENTIFIC OBJECTIVES 
 
The primary objective of the cruise was to maintain the collection of
hydrographic and biogeochemical data at the Hawaii Ocean Time-series
(HOT) station, also known as Station ALOHA (A Long Term Oligotrophic
Habitat Assessment). Free-drifting sediment traps were planned for
deployment for approximately 72 hours from the site to measure
sedimentation rates of particulate matter. CTD casts at three hour
intervals were planned to obtain temperature, salinity, dissolved
oxygen, flash fluorescence and beam attenuation profiles. Water samples
for analysis of dissolved nutrients, gases, and biomass were to be
collected with the CTD casts . Another free-drifting array to conduct a
primary production experiment was planned for a 12 hour deployment. Two
other stations were planned to be occupied during this cruise; Station
Kahe and Station Kaena. An optical plankton counter (OPC) was planned
to be towed on the return leg to Snug Harbor. ADCP measurements were
not made during this cruise because the shipboard ADCP was not
functioning. Water samples for ancillary investigations were to be
collected and experiments were to be conducted as time permitted.
 

2.	SCIENCE PERSONNEL 
 
	Dale Hebel - UH, JGOFS 
	Luis Tupas - UH, JGOFS 
	Lance Fujieki - UH, JGOFS 
	Terrence Houlihan - UH, JGOFS 
	Don Wright - UH, JGOFS 
	Angie Thomson - UH, JGOFS 
	Fernando Santiago-Mandujano - UH, WOCE	 
	Jefrey Snyder - UH, WOCE 
	Craig Nosse - UH, WOCE 
	Molly Lucas - UH, WOCE 
	Jinchun Yuan - UH, WOCE 
	Daniel Sadler - UH, Carbon Project 
	Robert Miller - UH, Zooplankton Project 
	Shevaun Fennell - UH, Trace Metal Project 
	Kristi Hanson - UH, Pigment Project 
	Mai Lopez - SIO, OPC/ADCP 
	Charles Stump - UW, Gas isotopes 
	Tanya Westby - UW, Gas isotopes 
	Jack DiTullio - Coll. Charleston, Picoplankton 
	Dave Jones - Coll. Charleston, Picoplankton 
	Hong Bin Liu - UH, Picoplankton 
	Karen Casciotti - UH, Trace gases 
	Bruce Monger - UH, Microplankton 
 

3.	GENERAL SUMMARY 
 
All objectives of the JGOFS and WOCE programs were accomplished.
Stations Kahe, Kaena and ALOHA were occupied. All core samples were
taken within the 36 hour CTD burst sampling period but several sampling
intervals were delayed because of on- going operations on deck. All
samples for ancillary projects were taken. The floating sediment trap
and the primary production array were successfully deployed and
recovered, no samples were lost during the in-situ incubation. Problems
were encountered with the CTD winch which did not brake properly during
descent. This was a major safety concern because during the retrieval
the package would slam onto the deck. A crane was used to lift the
package and retrieve the package once it was out of the water.
Additionally, the new rosette frame was spinning during deployment
which twisted the wire badly and required retermination of the CTD
cable after the first cast. The profiling natural fluorescence
instrument was lost during its initial deployment. The instrument was
apparently dragged under the ship and the cable was cut by the ships
propellers. There were no other equipment failures. The optical
plankton counter was towed on a series of transects through Station
ALOHA. After the transect the ship proceeded to Honolulu still towing
the v-fin which was retrieved just before the ship entered Honolulu
harbor.
 

4.	R/V MAURICE EWING, OFFICERS AND CREW, TECHNICAL SUPPORT 
 
The R/V Maurice Ewing provided adequate ship and technical support for
our work. There were several difficulties to overcome, such as the need
for radiation license transferring to use radioisotopes on the vessel,
the large beams on the port and starboard side of the vessel which
resulted in all operations being conducted from the stern, the great
height between the main deck and the crane on the port side which made
communication difficult and the CTD winch with did not break properly
which necessitated a revised recovery procedure.  There were other
difficulties which are outlined in the section below.  The officers and
crew were most helpful and accommodating. They showed enthusiasm and
concern for our work and were very flexible in receiving changes in our
operational schedule. Technical support during this cruise was
excellent. Personnel were available at any time to assist in our work
and made things much easier for us.
 

5.	DAILY REPORT OF ACTIVITIES 
 
July 26, 1995; Loading Day 1 
  
Although we were scheduled to mobilize our equipment on July 26th, Snug
Harbor called us on July 25 to bring the laboratory vans and other
heavy equipment for loading. The reason for this was that the UH Marine
Facility's crane was not adequate in scope to lift off or put container
vans on the ship. The large beams above the ship's port and starboard
gunnels of the back deck were a large obstacle as well as the great
height of the upper deck. The laboratory vans and other large equipment
were moved from the SNUG Harbor that day. All lighter deck equipment
and laboratory equipment were to loaded the following day.

July 27, 1995; Loading Day 2

All other equipment not loaded the previous day was loaded on this day.
The captain of the vessel was most conservative in terms of safety and
did not allow us to cross the CTD opening of the ship. All equipment
had to be handed across the railings or carried through the gangway.
The ship had a new CTD wire which we used. All electrical and
electronic connections were made for the CTD and the OPC/v-fin. The OPC
was connected to a towing winch to the A-deck. All lab equipment were
stowed away and secured. All instruments were tested and appeared
functioning. No problems were encountered.

July 28, 1995; Departure and at-sea

All hands arrived on ship at 0830. Ship departed at 0900. Fire and
emergency drills conducted at 0945 followed by safety briefing by
science officer, first mate and chief engineer. Arrive at Station Kahe
at 1200 and conducted a weight cast to be followed by the profiling
natural fluorometer  (PNF) cast. During the PNF down cast, when the
instrument was at a depth of about 130 m, the package swung inboard
under the ship. The ship was trying to adjust position but the cable
remained beneath the ship. The cable then parted and was apparently cut
by the propellers of the ship. The cast was aborted and the 1000 m CTD
cast was conducted. An apparent instrumentation failure was noted
during the up-cast. When the package was retrieved two problems were
noted. the first problem was a kink in the wire which would necessitate
retermination of the cable. The second problem was that the package
could not be gently lowered unto the deck of the ship.  The science
officer would look into this problem. The instrument package was
inspected and no problems were apparent. The wire was reterminated and
a second cast was made at 1615 and completed at 1745.  All operations
and sampling accomplished by 1800. Transit to Station Kaena. Arrive
Station Kaena at 2100. Conduct CTD to near bottom, completed at 2300,
slowly started transit to Station ALOHA while sampling.
 
July 29, 1995; At-sea 
 
Arrive at the center of Station ALOHA at 0400 and commenced sediment
trap deployment. Rough sea state. After deployment the ship transited
to the center of Station ALOHA and commenced with the 36 hour burst
sampling period. Because of the condition of the wire, it was decided
that the WOCE deep cast be conducted at the end of the 36 hour sampling
period. CTD burst sampling commenced at 0800 with the JGOFS casts. CTD
casts maintained at 3 hour intervals. Some problems were encountered
with determining the correct wire speed. Some delays with the 3-hour
interval CTD period were encountered because of the high-volume water
pump sampling occurring in between the scheduled deployment times. Net
tows were conducted in the evening

July 30, 1995; At-sea

CTD casts continued at 3 hour intervals. Go-Flo cast from the stern
conducted at 0130, finished at 0300. Primary production array
deployment commenced at 0600. CTD casts continued at 3 hour intervals.
Zooplankton tow conducted at noon and midnight.  High-volume pumping
conducted in between CTD casts caused some delay in the schedule.
Retrieval of primary production array commenced at 1930. No samples
were lost. A delay of 3 hours was caused by the retrieval of the
primary production array. CTD casts continued at 3 hour intervals.

July 31, 1995; At-sea

Burst sampling continues. WOCE deep cast commenced at 1300. CTD casts
continue for special projects at 1800. The CTD cable was again
reterminated at 0800 because of several kinks in the wire.  Zooplankton
tow and large volume pump sampling conducted in between casts.

August 1, 1995; At-sea

CTD worked continues with final cast accomplished at 0330.  Departed
towards sediment traps at 0400. we were using the last email message
which was received on July 30 to locate the traps. No fax or email
messages were received afterwards. Sediment trap recovery started at
0830 and completed by 1030. OPC/V-fin deployed and survey of Station
ALOHA conducted at 1100. Transit to Station ALOHA at 0600.
 
August 2, 1995; At-sea and return to Honolulu 
 
	V-fin retrieved at 0500. Proceed to Snug Harbor and arrive at
 0800. Commenced off loading. All equipment and personnel cleared from
ship at 1130.
 

6.	ANCILLARY INVESTIGATIONS AND SPECIAL PROJECTS 
 
1. Zooplankton sampling - B. Miller 
2. Trace metal water sampling - S. Fennell 
3. DIC water sampling - D. Sadler 
4. Optical plankton counter - M. Lopez 
5. Plant pigment samples - K. Hanson 
6. Picoplankton project - J. Ditullio, D. Jones, H. Liu 
7. Trace gases - K. Casciotti 
8. Microplankton samples - B. Monger 
9. Gas Isotopes - C. Stump, T. Westby 
 

7.	SAMPLES TAKEN FOR OTHER INVESTIGATORS 
 
1. DIC water samples for C.D. Keeling, SIO-UCSD 
2. DIC water samples for P. Quay, U. Washington 
3. Filtered seawater samples for H. Thierstein, Zurich 
4. Seawater samples for G. Luther, U. Delaware 
5. Seawater samples for F. Sansone, B. Popp, U. Hawaii 
6. Seawater for E. Laws, U.Hawaii 
7. Seawater for B.Midson, U. Hawaii 
 

8.	SAFETY AND OTHER RELATED ISSUES 
 
The following are safety related issues regarding our operations on the
vessel.
 
1. CTD operations - The CTD winch which was operated on the vessel
lacked the proper breaking mechanism. This resulted in our CTD being
crashed several times on the deck of the ship which was potentially
dangerous to anyone in the vicinity. We resolved the problem by using
the ship's crane to take the load off the winch after the package was
lifted out of the water. This however, required several more personnel
and the operation had to be properly coordinated to avoid injury to
personnel. This also increased the time it took to conduct a recovery
operation. Fortunately, sea conditions were not too rough and we could
take the time necessary for this manuever. Another probelm involves the
lack of correct information regarding the winch speed which is
important for our work. The CTD winch is greatly lacking in operational
quality and is unsuitablefor proper CTD operations.

2. Portside operations - We found difficulty in deploying and our
retrieving instrumentation from the port side because of the great
height between the main deck and the A-deck where the crane is
located.  Communication between the crane operator and deck operator
was almost impossible. Because of this, we lost an instrument during
deployment.  The instrument was drageed under the ship and the cable
was cut by the propellers. Delays in communication were a factor in the
loss.

3. Ship to shore communications - It was not apparent to us on-board
immediately but we did not have communication with any shore based
institution for the last 3 days of our cruise. One of our operations
required the transmission of satellite information from the University
of Hawaii to the ship. Our shore personnel were unable to send us the
information by fax, INMARSAT or even single side-band radio. Even
personnel at LDEO were unable to get in touch with the ship. This was a
cause for great concern by the principal investigators. Fortunately, we
were able to recover our at-sea instrumentation with the minimal
information we had on-board ship.

4.  Back deck operations - We were unaware of the beams running along
and above the port and starboard side railings of the after deck. This
forced us to conduct all deployment and recovery operations off the
stern which is not desirable. Again sea conditions were calm enough to
do our deck operations but rougher sea conditions would have made it
unsafe.

Despite the above mentioned difficulties, were were able to accomplish
the major objectives of the cruise. We would like to thank the crew and
science support personnel who helped us overcome these difficulties.
They were very professional an willing to accomodate our needs.