HOT-47: Chief Scientist Report

Chief Scientist: L. TUPAS

Cruise Dates: May 18-23, 1993
Vessel: R/V/ New Horizon
Operator: Scripps Insitution of Oceanography, UCSD
Master: Captain John Manion
Resident Marine Technician: Seth Mogk
Ship Scheduling Office: Elizabeth Rios


Science Personnel:

Luis Tupas- UH Scientist, JGOFS
Dale Hebel- UH Scientist, JGOFS
Christopher Carillo- UH Tehnician, JGOFS
Jefrey Snyder- UH Tehnician, WOCE
Richard Muller- UH Tehnician, WOCE
Christopher Measures- UH Scientist
Florence Thomas- UH Scientist
Lance Fujieki- UH Graduate Student
Ricardo Letelier- UH Graduate Student
Daniel Sadler- UH Graduate Student
Charles Holloway- UH Graduate Student
Hongbin Liu- UH Graduate Student
Jinchun Yuan- UH Graduate Student
Reka Domokos- UH Graduate Student
Mike Mulroney- Univ. of Rhode Island, Scientist


General Summary

All objectives of the JGOFS and WOCE Programs were accomplished. All
core samples were taken and the 36 hour CTD burst sampling was
maintained without interruption. We were able to recover IES 1, 3 and
4. IES 2, which is located at Station ALOHA did not respond to repeated
interrogations but the release code was transmitted anyway. A surface
search was conducted, however, the IES did not transmit any transponder
or VHF signal.  We continued to monitor the radio frequency and kept
watch for the strobe during the 36 hours we remained at ALOHA for core
work. A final interrogation and search was conducted after the core
work but the IES was not to be found. We maintained surveillance of IES
2 (if it had surfaced) even during the recovery of IES 3. We
successfully deployed an IES at Station ALOHA and another at newly
named Station Kaena. The cruise also supported ancillary investigations
conducted by UH scientists and graduate students. In general, it was a
very successful cruise with no major equipment failures and no injuries
to personnel.


Daily reports

May 18, 1993, Tuesday

Although I had scheduled an assembly time of 0700, science personnel
continued to report in until 0750. We departed promptly at 0800 for
Station Kahe. At 0830, the resident marine technician, Seth Mogk, gave
us the standard briefing on ship rules and safety procedures. Captain
Manion joined the meeting later to conclude the briefing. A fire and
abandon ship drill was held at 0900. We arrived at Station Kahe at
1130. We proceeded with a 300 m weight cast, a PNF cast, and a 1000 m
cast. Sampling of the 1000 m cast was completed at 1500 and we
proceeded to the location of IES 4 (22o45'N, 157o40'W). We arrived at
IES 4 at 1130 hours. Mike Mulroney proceeded to interrogate the IES and
we were able to establish its location. The release code was given and
we waited for the IES to surface.


May 19, 1993, Wednesday

The IES surfaced and was located and brought on board at 0130. We then
proceeded to the eastern boundary of Station ALOHA and arrived at 0500.
Sediment traps were deployed upon arrival at 22o 46.6'N, 157o51.4'W and
was finished at 0700. After deployment, the ship moved to the the
center of the circle (22o 45'N, 158oW). Upon arrival at 0730 Mike
Mulroney began interrogation of IES 2, which did not respond. The IES
did not respond despite all attempts to communicate with it. The
release code was eventually trnasmitted and we conducted a surface
search after a period of waiting. The surface search proved negative
and we commenced with the deployment of a new IES. The new IES was
deployed at 22o45.05'N, 158o00.08'W at 0930 and we waited until we
received confirmation that it landed at the bottom and was properly
trnasmitting. We then proceeded our standard time-series data
collection. A PNF cast was conducted at 1100. The WOCE deep cast was
conducted at 1130 and completed at 1530. We suspended work to proceed
outside the circle to pump out the ships sewage tanks. We then returned
to the center and started the 36 hour burst sampling at 1800. This
continued every 3 hours for 36 hours without interruption.

May 20, 1993, Thursday

The Go-Flo cast commenced at 0130 and was completed at 0300.  The
primary production array was deployed at 0600. CTD casts were continued
throughout the day. PNF cast was conducted at 1200. The primary
production array was retrieved at 2000. CTD casts continued throughout
the day without interruption.

May 21, 1993, Friday

The last CTD cast of the burst sampling was completed at 0400. The ship
then proceeded outside of the circle to pump out continued CTD casts at
0800. PNF cast was conducted at 1100. CTD casts continued throughout
the day. One cast was aborted due to poor signal transmission. A new
termination was made and the error was corrected. The final CTD cast
for Station ALOHA was completed at 1900. We then proceeded with another
attempt to communicate with IES 2 and a surface search was conducted.
We left Station ALOHA at 2300 for IES 1.


May 22, 1993, Saturday

We arrived at IES 1 at 0130 and proceeded with a 4500 m cast for Flo
Thomas. A surface net tow for Ricardo Letelier commenced at 0230 and
completed at 0300. Mike Mulroney proceed to communicate with the IES at
0300. The IES was located and the release signal was transmitted. The
CTD was brought onboard at 0500. The IES was recovered at 0545. We then
proceeded to the location of the sediment traps. The sediment traps
were recovered at 0945 at 22o41.64'N, 158o 41.91'W. After recovery we
moved to the location of IES 3. A 4500m CTD cast was conducted at the
IES 3 location for Flo Thomas at 1300 and was completed at 1700. Mike
Mulroney proceed to communicate with IES 3, but was unsuccessful.  The
release signal was nevertheless transmitted and we conducted a surface
search. We located and recovered the IES at 2100. We then proceeded to
the possible deployment site near Kaena point for a new IES.

May 23, 1993, Sunday

We arrived at the designated deployment site (21o53'N, 158o15'W) and
commenced a bathymetric survey at 0100. Station was designated as
Waimea. We tried to locate a level area of a depth between 2000 to 3000
m but could not locate one within the 5 square mile area. We moved to
21o47'N, 158o25'W and conducted another bathymetric survey at 0400. A
suitable site was located and the IES was deployed at 0630 at
21o50.76'N, 158o21.84'W, at a depth of about 2600 m. Station was
designated Kaena. A CTD cast to the near bottom commenced at 0730 and
completed at 0945. We confirmed the proper operation of the new IES and
proceeded back to Honolulu at 1000. We arrived at 1630 hours.


Other work conducted

1. Chris Measures, Jinchun Yuan -Iron and aluminum analysis
2. Ricardo Letelier -Biology of Trichodesmium
3. Hongbin Liu -Bacterial growth experiments
4. Charles Holloway -Thorium measurements
5. Florence Thomas -Oxygen sensor calibration
6. Luis Tupas, Dale Hebel -Leucine uptake, chlorophyll extraction
7. Christopher Carillo, Daniel Sadler -Inorganic carbon analysis