Cruise ID: KM0621
Departed: July 11, 2006 at 0900 (HST)
Returned: July 15, 2006 at 0730
Vessel: R/V Kilo Moana
Operator: University of Hawaii
Master of the Vessel: Captain Bryon Wilson
Chief Scientist: Fernando Santiago-Mandujano
OTG Electronics/Deck Operations Technicians: Steve Poulos, Gabe Foreman
1. SCIENTIFIC OBJECTIVES
The objective of this cruise was to maintain a collection of
hydrographic and biogeochemical data at the Hawaii Ocean Time-series
(HOT) stations. Five 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 July 11 for about 2 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,
158W. This is the main HOT Station and was to be occupied for 3 days
from July 12 to 14.
3) Station 51, is the site of the MOSEAN Mooring, located at 22 46.009'N,
158 5.533'W was to be occupied on July 15 for about 30
minutes.
4) Station 50, is the site of the WHOTS Mooring, located at 22 46.1 N,
157 53.4 W was to be occupied on July 15 for about 30
minutes.
5) Station 6, referred to as Station Kaena, is located off Kaena Point
at 21 50.8'N, 158 21.8'W was to be occupied on the 4th day of the cruise
for about 2 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. After these operations, the ship was to transit to
Station ALOHA.
Upon arrival at Station ALOHA, the free-drifting sediment trap array
was to be deployed. The sediment trap array was to stay in the water
for about 52 hours. This was followed by two 200 m and one 100 m CTD casts
to collect water for incubation experiments. After this, an array with
incubation experiments (gas array)was to be deployed for 24 hours. A
full-depth CTD cast was to be conducted afterwards, followed by 1000-m
CTD casts at strict 3 hour intervals for at least 36 hours for
continuous and discrete data collection, ending with another full-depth
CTD cast.
One free-drifting array was to be deployed for 12 hours for incubation
experiments on July 13.
A plankton net was to be towed near noon and midnight for 30-min intervals
on July 12 and 13 at Station ALOHA.
C. Mahaffey was to deploy her hand-held plankton net on July 13
for about 30 min.
After CTD work at Station ALOHA was accomplished, the ship was to
transit to recover the floating sediment trap array.
After recovering the sediment traps, the ship was to transit to Sta. 51
to conduct a 200-m CTD cast, and then back to Station ALOHA to conduct
one more 1000-m CTD cast, and light casts (PRR, AC9/FRRf). After this
the ship was to transit to Sta. 50 to conduct a 200-m CTD cast.
After operations at station ALOHA ended, the ship was to transit to
Station 6 (Kaena).
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 transit back to Snug Harbor.
A Profiling Reflectance Radiometer (PRR) was to be deployed for half-hour
periods near noon time on July 12, 13 and 14.
A package including a Wet Labs AC9, a Chelsea Fast Repetition Rate
Fluorometer (FRRf), and a SeaBird Seacat was to be used to profile the
upper 200 m at Sta. ALOHA at noon time on July 13 and 14, and
in the early morning on July 14.
An Automated Trace Element Sampler (ATE) was to be deployed once
on Jly 14.
The following instruments were to collect data throughout the cruise:
shipboard ADCP, thermosalinograph, and two anemometers.
2. SCIENCE PERSONNEL
BEACH group:
Cruise Participant Title Affiliation
Karin Bjorkman (Watch Leader) Research Specialist UH
Susan Curless Research Associate UH
Ken Doggett Research Associate UH
Lance Fujieki Computer Specialist UH
Eric Grabowski (Watch Leader) Research Associate UH
Adriana Harlan Technician UH
Claire Mahaffey Research Specialist UH
Cynthia Peacock Technician UW
Dan Sadler Research Associate UH
Blake Watkins Marine Engineer UH
Doug White Technician UH
PO group:
Paul Lethaby Research Associate UH
Damion Rosbrugh Undergraduate Student UH
Fernando Santiago-Mandujano Chief Scientist (Res. Assoc.) UH
Justin Smith Undergraduate Student UH
Jefrey Snyder Marine Technician UH
John Yeh Graduate Student UH
3. GENERAL SUMMARY
Operations during the cruise were conducted as planned. The primary
production array was lost during recovery on July 13. Only the spar
buoy and floats were recovered.
One 1000-m CTD cast was conducted at Kahe station. Twelve 1000-m CTD
casts, two deep casts, two 200-m and one 50-m CTD casts were conducted
at Station ALOHA. One 250-m CTD cast was conducted near the MOSEAN mooring
(station 51), and one 200-m cast was conducted near the WHOTS mooring
(station 50). One 2400-m CTD cast was conducted at Station Kaena.
The array of floating sediment traps, the gas array, and the primary
productivity incubation array were deployed and recovered without
incidents, with the exception of the primary productivity array, which
was lost during recovery. The arrays drifted SW.
Three net tows were conducted at night and three during the day.
The AC9/FRRf was deployed at noon once, and once at night.
The PRR was deployed three times at noon.
The ADCP ran without interruption throughout the cruise, as well as the
thermosalinograph, and the ship's two anemometers. The ADCP showed a
persistent southwestward current of up to 1/2 kt in the upper 100 m.
Winds were easterlies between 15 and 25 kt during the cruise.
We arrived back at Snug Harbor on July 15 at 0730.
Various Navy ships, planes and helicopters were present
near the study area, apparently conducting exercises as part of RimPAC.
The R/V Kilo Moana continues to maintain the excellent ship
support for our work. 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. OTG personnel were
available at any time to assist in our work and made things much easier
for us.
5. DAILY REPORT OF ACTIVITIES (HST)
July 10, 2006; Loading Day
Equipment loaded during this day, and the CTD system was tested.
Container vans and heavy equipment were loaded on July 3rd.
July 11, 2006
The ship departed from Snug harbor at 0900. Safety briefing by the
Captain conducted at 1000, followed by a science meeting in which
cruise activities were briefly reviewed, and safety issues were
addressed.
Fire and abandon ship drills conducted at 1030.
Arrived at Kahe Station at 1145. CTD wire weight cast (400 lb) to 500
m, during which J. Snyder inspected the CTD wire. An on-deck CTD-wire
tension test to 2000 lb was conducted at 1230.
The Profiling Reflectance Radiometer (PRR) was deployed at 1300.
A 1400-m CTD cast was conducted at 1320. After the cast ended, the ship
headed to station ALOHA. The altimeter was successfully tested during
this cast.
The ship arrived to Station ALOHA at 2210. The sediment traps array was
deployed at midnight.
July 12, 2006
One 200-m CTD cast was conducted at 0010 after the sediment traps
deployment. One 200-m and one 50-m CTD casts were conducted before the gas
array deployment.
The gas array was deployed at 0500.
One deep CTD cast was conducted at 0550. The altimeter signal was
intermittent near the bottom, but the pinger signal was very clear.
Four 1000-m CTD casts were conducted this day. The ISUS was installed
in the rosette and connected to the CTD before these casts, and
worked properly.
Two net tows were conducted near noon, and one at night.
Easterlies at 20-25 kt.
July 13, 2006
Eight 1000-m CTD casts were conducted on this day, and the 36-hr CTD
burst period ended with a second deep cast that started at 2300.
The gas array was recovered at 0745, at 22 39.8'N, 159 11.9'W, about
12 nm SW from ALOHA Station.
The primary productivity array was deployed at 0600. The array was
lost during recovery in the evening of July 13. The array's line
snagged around the rudder post/propeller, and evenutally the line
severed. Only the spar buoy and floats were recovered. The array drifted
about 8 nm SW from the center of ALOHA to 22 43.4'N, 158 4.6'W.
One AC9/FRRf cast was conducted at noon time.
One PRR cast was conducted at noon time.
Two net tows were conducted at night and one near noon.
Easterly winds at 15-20 kts. It rained sporadically at night and in
the morning.
July 14, 2006
One 250-m CTD cast was conducted near the MOSEAN mooring (Station 51),
and one 200-m CTD cast near the WHOTS mooring (Station 50).
The sediment traps array was recovered at 0630 at 22 36.7'N, 158 22.7'W.
The array drifted SW almost 23 nm from ALOHA Station.
Once PRR cast was conducted at 1245.
One AC9/FRRf cast was conducted at 0315, at Station ALOHA.
One near-bottom cast was conducted at Station Kaena (Station 6).
Easterly winds at 15-20 kt. It rained sporadically.
July 15, 2006
Arrived at Snug Harbor at 0730. Full off-load.
HOT program sub-components
Investigator: Project/Institution:
----------------- --------------------
Dave Karl Core Biogeochemistry/UH
Roger Lukas Hydrography/UH
Bob Bidigare HPLC pigments/UH
Mike Landry Zooplankton dynamics/UH
Mark Abbott/Ricardo Letelier Optical measurements/OSU
Ancillary programs:
Investigator: Project/Institution:
----------------- --------------------
Charles Keeling CO2 dynamics and intercalibration/SIO
Paul Quay DI13C and O isotopes/UW
Penny Chisholm Prochlorococcus population dynamics/MIT
Zehr/Church/Montoya Diversity and activities of nitrogen-fixing microorganisms/UH