HOT-179: Chief Scientist Report

Chief Scientist: F. SANTIAGO-MANDUJANO

           HOT-179 Chief Scientist's Cruise Report
                        R/V Kilo Moana
                       March 8-12, 2006

Cruise ID: KM0608
Departed:  March 8, 2006 at 0900 (HST)
Returned:  March 12, 2006 at 0730
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: Tim McGovern, Daniel Fitzgerald

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 March 8 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 March 9 to 11.

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 the 4th day of the cruise 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 the 4th day of the cruise 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.

 Upon arrival at Station ALOHA, the free-drifting sediment trap array
was to be deployed, followed by four shallow CTD casts (<200 m) to
collect water for incubation experiments. The sediment trap array was
to stay in the water for about 52 hours. 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 March 10. 

 A plankton net was to be towed near noon and midnight for 30-min intervals
on March 9 and 10 at Station ALOHA.

 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
two more 1000-m CTD casts, and light casts (PRR, AC9/FRRf).  At the end
of these operations, the ship was to transit to Station 50 to conduct a
200-m CTD cast.  After conducting these 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 transit back to Snug Harbor.

 A Profiling Reflectance Radiometer (PRR) was to be deployed for half-hour
periods near noon time on March 8, 10 and 11.

 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 March 10 and 11, and
in the early morning on March 11.

 An Automated Trace Element Sampler (ATE) was to be deployed once 
on March 11.

 One ARGO float was to be deployed at Station ALOHA on the last day of
the cruise by K. Heinze.

 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 Björkman			 Research Specialist		UH
 Matt Church			 Scientist			UH
 Ken Doggett 			 Research Associate		UH
 Allison Fong			 Graduate Student		UH
 Lance Fujieki (Watch Leader)	 Computer Specialist          	UH
 Adriana Harlan		  	 Technician			UH
 Claire Mahaffey		 Research Specialist		UH
 Cecile Mioni			 Volunteer				
 Blake Watkins			 Marine Engineer		UH

PO group:

 Suzanne Defelice		 Research Associate		UH
 Pollyanna Fisher		 Undergrad Student		UH
 Lauren Goodmiller		 Undergrad Student		UH
 Paul Lethaby (Watch Leader)	 Research Associate		UH
 Fernando Santiago-Mandujano	 Chief Scientist (Res. Assoc.)	UH
 Steven Tottori			 Marine Technician		UH

Others:

 Maureen Coleman		 Scientist			MIT 
 Edward DeLong		 	 Scientist			MIT
 Kurt Heinze			 Technician			UW
 Zackary Johnson		 Scientist			UH
 Tracy Mincer			 Scientist			MIT
 Matthew Sullivan		 Scientist			MIT
 Anne Thompson			 Scientist			MIT
 Jacob Waldbauer		 Scientist			MIT

3.  GENERAL SUMMARY

 
 Operations during the cruise were conducted with some changes in the
schedule due to the failure of the CTD winch during the first deep
cast, and also because of delays caused by transiting to recover the
gas array and sediment traps, which drifted farther than expected.

 One 1000-m CTD cast was conducted at Kahe station.  Twelve 1000-m CTD
casts, two deep casts, (~3000 m, and 4700 m), five casts shallower than
200-m were conducted at Station ALOHA. One 1000-m CTD cast and one
200-m cast were conducted near the MOSEAN mooring (Station 51).

 The array of floating sediment traps, the gas array, and the primary
productivity incubation array were deployed and recovered without
incidents. The arrays drifted rapidly northwestward.

 K. Heinze deployed an ARGO float at ALOHA Station.

 Three net tows were conducted at night and three during the day.

 The PRR and AC9/FRRf were deployed as scheduled, with the exception of the
AC9/FRRf March 10 deployment, which was cancelled due to time constraints.

 The Automated Trace-Element Sampler was successfully used to collect
one trace metal sample.

 The ADCP ran without interruption throughout the cruise, as well as the
thermosalinograph, and the ship's two anemometers. 

 Winds were from the southeast at about 20-25 kt during the cruise, with
a large swell.

 We arrived back at Snug Harbor on March 12 at 0730. Full off-load took 
place immediately.


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.

 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)

March 7, 2006; Loading Day

 Equipment loaded during this day. CTD wire was re-terminated and CTD 
system tested. 

March 8, 2006

 The ship departed from Snug harbor at 0900.  Safety briefing by the
Captain conducted at 0930, followed by a science meeting in which
cruise activities were briefly reviewed, and safety issues were
addressed. This was followed by a meeting with the Captain, Chief
Mate, OTG and PO personnel to discuss methods to improve the safety
of the CTD recovery during casts.

 Fire and abandon ship drills conducted at 1030.

 Arrived at Kahe Station at 1150. A weight cast (400 lb) to 500 m was 
conducted. 

 The Profiling Reflectance Radiometer (PRR) was deployed at 1230

 A CTD 1000-m CTD cast was conducted at 1300. After the cast
ended, the ship headed towards Station ALOHA. 

 The ship arrived to Station ALOHA at 2130. A 100-m CTD cast was conducted,
followed by the sediment traps array deployment at 2350. 

March 9, 2006

 One 200-m and two 100-m CTD casts were conducted after the sediment traps
deployment at Station ALOHA.

 The gas array was deployed at 0400.

 One deep CTD cast was conducted at 0435. The cast had to be aborted
at 3000 dbar due to problems with the CTD winch. The CTD was brought
on board and the winch was repaired and tested with the dead weight at
the end of the wire.
 
 Six 1000-m CTD casts were conducted this day. The rosette hit the
back of the ship during the recovery of cast 8. One of the rosette
weight mounts broke and some of the welded joints cracked. The CTD frame
also was warped by the impact. The rosette was deemed safe to continue
using it. The CTD sensors were tested and seemed to be working correctly.

 Two net tows were conducted near noon.

 Southeasterlies at over 25 kts, with large swell.

March 10, 2006

 Six 1000-m CTD casts were conducted on this day.

 The gas array was recovered 23 nm NW from ALOHA Station. One CTD
cast from the 36-hr burst period had to be cancelled due to the transit
time to recover the array.

 The primary productivity array was deployed at 0545 and recovered at
2000 without any problems. 

 Two consecutive PRR casts were conducted at 1350, and at 1410. 
The AC9/FRRf cast was canceled due to scheduling conflicts. 

 Three net tows were conducted at night and one near noon.

 Southeasterly winds at 20-25 kts, with large swell.

March 11, 2006

 One 4700-dbar and one 500-dbar CTD casts were conducted at ALOHA. 

 One 1000-m and one 500-m CTD casts were conducted near the MOSEAN mooring.

 The sediment traps array was recovered at 1000. The array drifted NW
about 38 nm from ALOHA Station.

 One AC9/FRRf cast was conducted at 0415, and two consecutive casts
were conducted at 1430 near the MOSEAN mooring.

 One PRR cast was conducted at 1330 near the MOSEAN mooring.

 K. Heinze deployed an ARGO float after all operations ended at Station
ALOHA.

 Winds of about 20 kt from the southeast

March 12, 2006

 Arrived at Snug Harbor at 0730. Full off-load.

Sub component programs:

Investigator:                   Project/Institution:
-----------------               --------------------
Bob Bidigare                    HPLC pigments/UH
Mike Landry			Zooplankton dynamics/UH
John Dore			CO2 dynamics/UH
Claire Mahaffey			Assessment of Nitrogen Fixation Rates/UH

Ancillary programs:

Investigator:                   Project/Institution:
-----------------               --------------------
Charles Keeling                 CO2 dynamics and intercalibration/SIO
Mark Abbott/Ricardo Letelier    Optical measurements/OSU
Paul Quay			DI13C and O isotopes/UW
Penny Chisholm			Prochlorococcus population dynamics/MIT
Matthew Church/Allison Fong	Diversity and activities of nitrogen-fixing
				microorganisms/UH

Ancillary research during this cruise:

Investigator:                   Project/Institution:
-----------------               --------------------

Edward DeLong			Community genomics of stratified
(MIT Group)			Prochlorococcus, picoplankton, and virus
				communities at station ALOHA/MIT	
Zackary Johnson			Bacterial Chlorophyll containing organisms 
				genetic diversity estimation/UH
Kurt Heinze/Steve Riser		ARGO float deployment/UW