Hawaii Ocean Time-series (HOT)
in the School of Ocean and Earth Science and Technology at the University of Hawai'i at Manoa


HOT-145: Chief Scientist Report


Chief Scientist: F. SANTIAGO-MANDUJANO


           HOT-145 Chief Scientist's Cruise Report
                  R/V Ka'Imikai-O-Kanaloa
                    February 24-28, 2003

Cruise ID: KOK0304
Departed:  February 24, 2003 at 0900 (HST)
Returned:  February 28, 2003 at 0730
Vessel:  R/V Ka'Imikai-O-Kanaloa
Operator:  University of Hawaii
Master of the Vessel: Captain Ross Barnes
Chief Scientist: Fernando Santiago-Mandujano
STAG Electronics Technician: Gabe Foreman
STAG Deck Operations: David Gravatt

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 February 24 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, 
158W. This is the main HOT Station and was to be occupied for 3 days 
from February 25 to February 27.

3) 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 February 27 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, a net tow was to be conducted, followed
by the deployment of a free-drifting sediment trap array. 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.

 One free-drifting array was to be deployed for 12 hours  for 
incubation experiments on February 26. 

 A plankton net was to be deployed near noon and midnight on February 25
and 26 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 return to Sta. ALOHA to continue light
cast operations, after which 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) and a Tethered Spectral 
Radiometer Buoy (TSRB) were to be deployed for half-hour periods
near noon time on each day.

 A package including a Wet Labs AC9, a Fast Repetition Rate Fluorometer 
(FRRf), and a SeaBird Seacat was to be used to profile the upper 200 m
at Sta. ALOHA for one-hour periods on February 26 and 27.

 An Automated Trace Element Sampler (ATE) was to be hand deployed to
collect a 10 m sample at Sta. ALOHA on February 27.

 An set of instruments were to be used by C. McNaughton (Antony D. 
Clarke's group) to evaluate the size distribution and vertical structure 
of marine aerosols above the ship.

 The following instruments were to collect data throughout the cruise: 
shipboard ADCP, thermosalinograph, fluorometer, and two anemometers.


2.  	SCIENCE PERSONNEL

JGOFS group:
 Karin Björkman                  Research Specialist            UH
 Tara Clemente (Watch Leader)	 Research Associate	        UH
 Anne Gasc   	 		 Research Associate		UH 
 Lance Fujieki			 Computer Specialist          	UH
 Tom Gregory			 Research Associate		UH
 Dan Sadler			 Research Associate		UH
 Valerie Franck			 Scientist			UH
 Cecelia Sheridan	         Graduate Student    		UH 

PO group:
 Yoshimi Rii			 Research Associate       	UH
 Daniel Fitzgerald (Watch Leader) Research Associate       	UH
 Mark Valenciano                 Electronics Technician     	UH
 Yves Veillerobe                 Undergraduate Student 		UH/GES
 Fernando Santiago-Mandujano	 Chief Scientist (Res. Assoc.)	UH

Others:
 Cameron McNaughton	         Graduate Student	        UH/HiGEAR
 Laurie Juranek		         Graduate Student    		UW 


3.  GENERAL SUMMARY

 
 Operations were conducted as planned, without interruptions.

 Fourteen 1000-m CTD casts and two deep casts (~4740 m) were conducted 
at Station ALOHA.  One 1000-m CTD cast was conducted at station
Kahe. One near-bottom cast (~2500 m) was conducted at Station 6. 

 The array of floating sediment traps and the incubation array
were deployed and recovered without incidents. The sediment traps array
drifted northwestward. 

 C. Sheridan completed successfully 6 plankton net tows. 

 The PRR, TSRB and AC9/FRRf were deployed as planned.

 C. McNaughton used his set of instruments to evaluate the size distribution
and vertical structure of marine aerosols. One of his three instruments
did not operate during the cruise due to a broken electronic connection. 
Light scattering measured from the nephelometer showed clean marine 
conditions with scattering values as low as 9 Mm^-1 and only as high 
as 30 Mm^-1. These values represent pristine marine conditions.  Vertical 
visibility during cloud free periods extended beyond 7000m, the limit of 
instrument detection.  The height of the marine stratus clouds were also 
recorded by the visibility instrument (ceilometer).

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

 Winds were easterlies at 10-20 kt, and sea state 2-3.

 We arrived back at Snug Harbor on February 28 at 0730. Full off-load 
took place immediately.


4.  R/V KA'IMIKAI O KANALOA, OFFICERS AND CREW, TECHNICAL SUPPORT

 The R/V Ka'Imikai O Kanaloa 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 very good. STAG personnel were
available at any time to assist in our work and made things much easier
for us.

5.  DAILY REPORT OF ACTIVITIES (HST)

February 22, 2003; Loading Day

 Equipment loaded on this day (Van Labs were loaded earlier, on 
February 14). Terminated CTD wire and tested CTD system.

February 24, 2003

 The ship departed from Snug harbor at 0900. Fire and abandon ship
drills conducted at 0930, followed by a short science meeting during
which some of the cruise activities were briefly reviewed, and safety 
issues were addressed.

 C. McNaughton installed his marine aerosol observation instruments on
the port side of the ship just ouside the bridge.  Unfortunately the 
miniture-optical particle counter (mini-OPC) had a broken electronic 
connection and did not operate during the cruise.

 Arrived to Kahe Station at 1200 and a weight cast (400 lb) to 1000 m
was conducted during which M. Valenciano inspected the CTD wire. At
1300 the Profiling Reflectance Radiometer (PRR) and Tethered Spectral
Radiometer Buoy (TSRB) were deployed. 

 A 1000-m CTD cast was conducted at 1400, after which the ship headed 
towards Station ALOHA.

 Winds were easterlies at 10-20 kt. Sea state 3.

February 25, 2003

 Arrived at Station ALOHA at 2315 (February 24), and proceeded 
to conduct a net tow, followed by the deployment of the sediment traps. 

 The deep PO cast started at 0200 and ended at 0530 without
any problems. This cast was followed by the shallow PO cast, which
started the 36-hr CTD cast period.  A total of six 1000-m CTD casts
were conducted this day.

 Net tows were conducted at 0000, 1000, 1230 and 2200. 

 Winds were 10-20 kt easterlies, and 2-3 sea state.
 
February 26, 2003

 Seven 1000-m CTD casts were conducted during this day, ending the 36-hr
CTD cast period at 2100. A second deep cast was started at 2300. 

 The primary productivity array was deployed at 0600 and was retrieved
at 1830, the array drifted 1 nm east from the center of ALOHA Sta.

 One net tow was conducted at 0030 and one at 1000.

 The PRR, TSRB and AC9/FRRf were deployed at 1200.

 Winds were easterlies at 10-20 kt, and 2-3 sea state.

February 27, 2003

 The second deep CTD cast that started at 2300 on February 26 was completed
by 0215.

 The floating sediment trap array was recovered at 0645.  The array
drifted 15 nm northwest from the center of Station ALOHA.  One of the
array's buoys was missing upon recovery, and the lines connecting the
buoys were all tangled.

 One AC9/FRRf cast was conducted at 0300 at ALOHA Sta. PRR/TSRB 
and AC-9/FRRf measurements were conducted between 1100 and 1300 at ALOHA.

 A trace element sample was taken with the ATE at 1030 at ALOHA.

 A near-bottom cast (~2500 m) was conducted at 2000 at Station Kaena 
(Stn. 6), after which the ship headed back to Snug harbor.

 Winds were easterlies at 10-20 kt and sea state 3.

February 28, 2003

 Arrived at Snug Harbor at 0730. Full off-load took place immediately.


Sub component programs:

Investigator:                   Project/Institution:
-----------------               --------------------
Bob Bidigare                    HPLC pigments/UH
Mike Landry			zooplankton dynamics/UH
John Dore			CO2 dynamics/UH

Ancillary programs:

Investigator:                   Project/Institution:
-----------------               --------------------
Charles Keeling                 CO2 dynamics and intercalibration/SIO
Mark Abbott/Ricardo Letelier    optical measurements/OSU
Penny Chisholm/Erik Zinser	Prochlorococcus ecotype dynamics/MIT

Others:
Karin Björkman                  phosphorus cycling/UH
Antony D. Clarke		Hawai'i Group for Environmental Aerosol 
				Research (HiGEAR)