HOT-149: Chief Scientist Report
Chief Scientist: T. GREGORY
HOT-149 Chief Scientist's Cruise Report
Departed: June 18, 2003 at 0900 (HST)
Returned: June 22, 2003 at 0730 (HST)
Vessel: R/V Roger Revelle
Operator: Scripps Institution of Oceanography
Master of the Vessel: Captain David Murline
Chief Scientist: Thomas Gregory
Resident Marine Technicians: Gene Pillard and Geoff Ravenhill
1. SCIENTIFIC OBJECTIVES
The objective of this cruise was to continue building a collection of
hydrographic and biogeochemical data at the Hawaii Ocean Time-series
(HOT) stations. Three stations were to be occupied during the cruise,
in the following order:
1) Station 1, referred to as Station Kahe, is located at 21° 20.6'N, 158
° 16.4'W and was to be occupied on June 18 for about 3 hours.
2) Station 2: ALOHA (A Long Term Oligotrophic Habitat Assessment) is
defined as a circle with a 6 nautical mile radius centered at 22° 45'N,
158°W. This is the main HOT station and was to be occupied for 3 days
from June 19 to June 21.
3) Station 6, referred to as Station Kaena, is located off Kaena Point
at 21° 50.8'N, 158° 21.8'W and was to be occupied on June 21 for about
4 hours.
A single CTD cast was to be conducted at Station 1 to collect
continuous profiles of various physical and chemical parameters. Water
samples were to be collected at discrete depths for biogeochemical
measurements. PRR and TSRB measurements were also to be made.
Upon arrival at Station ALOHA, the deployment of a free-drifting
sediment trap array was to be conducted. After deployment, a
full-depth CTD cast was to be conducted followed by CTD casts at strict
3-hour intervals for at least 36 hours for continuous and discrete data
collection followed by another full-depth CTD cast. The primary
production array was to be deployed on June 20 for 12 hours. PRR, TSRB
and AC-9/FRRf operations were to be done around noon June 20 and 21 and
a nighttime AC-9/FRRf cast was to be executed at 0300 on June 21. The
drifting sediment trap array was to be recovered near dawn on June 21.
Plankton net tows were to be conducted near noon and midnight on June
19 and 20.
Following Station ALOHA operations, the ship was to transit to Station
6. A near-bottom CTD cast (~2500 m) was to be conducted at Station 6
including salinity samples for calibration, after which the ship was to
return to Snug Harbor.
The following instruments were to collect data throughout the cruise:
an ADCP, a thermosalinograph, fluorometer, and an anemometer.
2. SCIENCE PERSONNEL
PO Group:
Shimi Rii Research Associate UH
Daniel Fitzgerald Research Associate UH
Mark Valenciano Electronics Technician UH
Fernando Santiago-Mandujano Research Associate UH
(Watch Leader)
Jediah Bishop Undergraduate Student HPU
Santiago Andrioni Undergraduate Student HPU
Maya Iriondo Graduate Student UH
Rebecca Most Undergraduate Student UH
JGOFS Group:
Thomas Gregory Research Associate UH
(Chief Scientist)
Lance Fujieki Computer Specialist UH
Dan Sadler Research Associate UH
Eric Grabowski Research Associate UH
Evgeny Dafner Research Associate UH
Karin Bjorkman Research Specialist UH
Cecilia Sheridan Graduate Student UH
Karmin Kime Graduate Student UH
Karin Schlappa Graduate Student UH
Jena Kline Graduate Student UH
Stefan Helmreich Cultural Anthropologist MIT
3. GENERAL SUMMARY
All operations at Stations Kahe, Kaena and ALOHA were conducted as
planned.
Weather conditions were favorable throughout the cruise.
The thermosalinograph had problems and didn't start working properly
until 1700 (HST) on June 18. The ship's anemometer and ADCP ran
without interruption throughout the cruise.
We arrived back at Snug Harbor on June 22 around 0730. A complete
off-load took place immediately.
4. R/V ROGER REVELLE, OFFICERS AND CREW, TECHNICAL SUPPORT
The R/V ROGER REVELLE and her crew delivered exceptional ship support
for our work. The officers and crew were most helpful and accommodating
and are to be commended for maintaining high standards. They showed
enthusiasm and concern for our work and were very flexible in receiving
changes in our operational schedule.
5. DAILY REPORT OF ACTIVITIES (HST)
June 17, 2003; Loading Day
Equipment loaded on this day. The CTD wire was terminated and tested.
June 18, 2003
The ship departed from Snug harbor at 0900, two hours late due to last
minute loading and Honolulu harbor ship traffic. Safety briefings were
held immediately.
We arrived at Station Kahe at 1230 and immediately conducted the
PRR/TSRB deployment. Afterwards, we conducted a 1000 m CTD cast. The
package was back on deck at 1502 and we then began transit to Station
ALOHA.
June 19, 2003
We arrived at Station ALOHA around 2345 and executed a plankton net tow
shortly thereafter. Following the tow, we deployed the sediment trap
array. The first deep PO cast started at 0155 and was back on deck at
0535. We conducted six 1000 m casts this day.
Plankton net tows were conducted at 0018, 1011, 1304 and 2214.
June 20, 2003
The primary productivity array was deployed at 0445 and recovered at
2003.
Plankton net tows were conducted at 0100 and 1006.
The PRR and TSRB were deployed at 1212 and the AC-9/FRRf was deployed
at 1245.
Seven 1000 m casts were conducted this day. S2C15 (the second deep PO
cast) was initiated at 2303.
June 21, 2003
S2C15 was recovered at 0204 and concluded CTD operations at Station
ALOHA.
The sediment trap array was recovered at around 0645. Following
recovery we steamed back to Station ALOHA.
Upon arrival at Station ALOHA, the ATE sampler was deployed at 1100.
The PRR and TSRB were deployed at 1212 and AC-9/FRRf casts were
performed at 0305, 1251 and 1351.
Following the 1351 FRRf cast, we began steaming to Station Kaena.
A 2500 m cast was performed at Station Kaena at 2009.
June 22, 2003
We arrived at Snug Harbor at around 0730. A full offload took place
immediately.
Sub component programs:
Investigator: Project:
----------------- ----------
Bob Bidigare HPLC pigments/UH
Mike Landry zooplankton dynamics/UH
John Dore CO2 dynamics/UH
Ancillary programs:
Investigator: Project:
----------------- ----------
Charles Keeling CO2 dynamics and intercalibration/SIO
Mark Abbott/Ricardo Letelier optical measurements/OSU
Penny Chisholm/Erik Zinser Prochlorococcus ecotype dynamics/MIT