HOT-197 Chief Scientist's Cruise Report
R/V Kilo Moana
November 30 - December 4, 2007
Cruise ID: KM0722
Departed: November 30, 2007 at 0900 (HST)
Returned: December 4, 2007 at 0900
Vessel: R/V Kilo Moana
Operator: University of Hawaii
Master of the Vessel: Captain Richard L Meyer
Chief Scientist: Fernando Santiago-Mandujano
OTG Electronics/Deck Operations Technicians: Kuhio Vellalos, Tobin Chen
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. Four 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 November 30 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 December 1 to 3.
3) Station 52, is the site of the WHOTS Mooring, located at 22 40.208'N,
157 57.001'W was to be occupied on December 3 for about 1 hour.
4) 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 one 200 m CTD cast
to collect water for incubation experiments, and one 1000-m CTD cast to
collect water for the primary production array. After this, a light
cast (AC9/FRRf) cast was to be conducted, followed by the deployment of the
array with incubation experiments (primary production array) that was to be
in the water for 12 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.
Another free-drifting array (gas array) was to be deployed for 24 hours for
incubation experiments on December 2.
A plankton net was to be towed near noon and midnight for 30-min intervals
on December 1 and 2 at Station ALOHA.
After CTD work at Station ALOHA was accomplished, the ship was to
transit to recover the floating sediment trap array and the gas array.
After recovering the arrays, the ship was to transit to Sta. ALOHA to conduct
another CTD cast and two consecutive light casts (PRR, AC9/FRRf).
After operations at station ALOHA ended, the ship was to transit to
Station 52 to conduct a one-hour 200-m CTD yo-yo cast, after which the ship was
to transit to station Kaena.
A free drifting ARGO float was to be deployed upon departure from station
ALOHA on December 3.
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 November 30, December 1 and 3.
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 December 2 and 3, and
in the early morning on December 1.
The following instruments were to collect data throughout the cruise:
shipboard ADCP, thermosalinograph, and two anemometers.
2. SCIENCE PERSONNEL
Cruise Participant Title Affiliation
BEACH group:
Karin Björkman Research Specialist UH
Tara Clemente Research Associate UH
Susan Curless (Watch leader) Research Associate UH
Lance Fujieki Computer Specialist UH
Adriana Harlan Technician UH
Binglin Li Graduate Student UH
Donn Viviani Graduate Student UH
Brett Updyke Technician UH
Blake Watkins Marine Engineer UH
Sam Wilson Scientist UH
PO group:
Paul Lethaby Research Associate UH
Fernando Santiago-Mandujano Chief Scientist (Res. Assoc.) UH
Christin Shacat Research Associate UH
Justin Smith Undergraduate Student UH
Jefrey Snyder (Watch leader) Marine Technician UH
Others:
Rachel Foster Scientist UC Santa Cruz/Zehr
Misty Miller Technician UH/Rappe
Naomi Wagoner Technician UH/Rappe
Dana Swift Technician UW/Riser
3. GENERAL SUMMARY
Most of the operations during the cruise were conducted as planned, with
some delays in the schedule due to bad weather and a strong northwestward
current.
One 1000-m CTD cast was conducted at Kahe station. Eleven 1000-m CTD
casts, two 200-m, and two deep casts were conducted at Station ALOHA. One
1000-m CTD, and one 200-m cast were conducted near the WHOTS
mooring (station 52), which was located inside the ALOHA circle.
The array of floating sediment traps, the primary productivity
and gas incubation arrays were deployed and recovered without problems. All
arrays drifted NW.
Two net tows were conducted at night and two during the day.
The AC9/FRRf was deployed near noon two times, and one time at night.
The PRR was deployed three times near noon time.
A trace metal sample was taken (ATE).
The ADCP ran without interruption throughout the cruise, as well as the
thermosalinograph, and the ship's two anemometers.
Winds were changing from SW to NW at up to 25 kt during the cruise due
to the passage of a weather front, accompanied by intermittent rain. A large
swell of up to 18 ft from the NW was present. A northwestward surface current
of about 0.5 kt was persistent during the cruise.
We arrived back at Snug Harbor on December 4 at 0900.
4. R/V KILO MOANA, OFFICERS AND CREW, TECHNICAL SUPPORT
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.
Despite the adverse weather conditions, the captain and officers
were able to maintain good control on the vessel, which
allowed us to conduct all our deck operations, deployments and recoveries
in a smooth manner. Without their expertise and enthusiasm we would not
have been able to accomplish these operations.
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)
November 29, 2007; Loading Day
The equipment was loaded during this day.
November 30, 2007
The ship departed from Snug harbor at 0900. Safety briefing conducted
at 0930, followed by a science meeting in which cruise activities were
briefly reviewed, and safety issues were addressed. Fire and abandon
ship drills were conducted at 1010 for all personnel.
Arrived at Kahe Station at 1140. CTD wire weight cast (1,300 lb) to 500
m, during which J. Snyder inspected the CTD wire.
The Profiling Reflectance Radiometer (PRR) was deployed at 1245
A 1000-m CTD cast was conducted at 1313. After the cast ended, the ship
headed to station ALOHA.
The ship arrived to Station ALOHA at 2210.
December 1, 2007
Deployed sediment traps array at 0003.
Conducted one 200-m CTD cast at 0010 (s2c1).
Conducted one 1000-m CTD cast at 0150 (s2c2). Slow descent due to large swell
An AC9/FRRf cast was conducted at 0345.
The primary production array was deployed at 0505.
One deep CTD cast was conducted at 0640 (s2c3).
1000-m CTD cast at 1235 (s2c4).
1000-m CTD cast at 1520 (s2c5)
Primary production array recovered at 1812. The array drifted 3 nm north
1000-m CTD cast at 1833 (s2c6).
1000-m CTD cast at 2106 (s2c7).
Net tow conducted at 2210
1000-m CTD cast at 2250 (s2c8).
A large swell of about 15 ft from NW was present during the day. Winds
were 20-25 kt from SW, but switched direction from NW at 23 kt with the
entrance of a weather front at 1230, with rainfall.
December 2, 2007
200-m CTD cast at 0249 (s2c9)
Deployment of gas array at 0500
1000-m CTD cast at 0530 (s2c10).
Trace metal sample (ATE) at 0710.
1000-m CTD cast at 0813 (s2c11).
1000-m CTD cast at 1047 (s2c12).
Net tow at 1230.
PRR cast at 1305
AC9/FRRf cast at 1330
1000-m CTD cast at 1440 (s2c13)
1000-m CTD cast at 1730 (s2c14)
1000-m CTD cast at 2037 (s2c15)
Net tow at 2227
Near-bottom CTD cast at 2350 (s2c16).
Winds from NW at 20 kt. Intermittent rain.
December 3, 2007
The sediment traps array was recovered at 0600 at 22 28.55'N, 158 10.06'W.
The array drifted about 10.5 nm NW from ALOHA Station.
The gas array was recovered at 0700 at 22 48.63'N 158 5.37'W. The array
drifted about 6 nm NW from ALOHA.
1000-m CTD cast near the WHOTS buoy (located inside the ALOHA circle)
(s52c1).
The PRR was put in the water at 1100 and lowered to 75 m, but the operation
had to be canceled because the current was bringing the instrument near the
propellers. The officers were unable to effectively maneuver the ship due to
the large swell and lack of wind.
AC9/FRRf cast conducted at 1220. The second planned cast had to be cancelled
because the ship had to go out of the circle to pump sewage tanks, and
these two casts need to be conducted back to back.
A 200-m CTD cast was conducted near the WHOTS mooring. Could not conduct
yo-yo cast due to the increasing swell (s52c2).
The free drifting ARGO float was not deployed because it failed to
communicate while testing it on board.
Near-bottom CTD cast at station Kaena at 2113 (s6c1).
Winds decreased to less than 5 kt, but the swell increased up to 18 ft from NW,
and persisted throughout the day.
December 4, 2007
Arrived at Snug Harbor at 0900. 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/Carter Diversity and activities of nitrogen-fixing
microorganisms/UH
Various CMORE PI's CMORE RNA/DNA sampling/UH
Additional programs
Investigator: Project/Institution:
----------------- --------------------
Mike Rappe Marine bacterioplankton community
structure/UH
Dana Swift/Steve Riser ARGO float/UW
Sam Wilson Reduced gases in the upper ocean: The cycling
of methane, sulfide and nitrous oxide/CMORE/UH
Rachel Foster/Zehr Diversity and activities of nitrogen-fixing
microorganisms/UCSC