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


HOT-62: Chief Scientist Report


Chief Scientist: D. HEBEL


HOT 62 Cruise Report
R/V Moana Wave
4-9 April, 1995



Personnel List:
---------------

WOCE group:

Jefrey Snyder (Watch Leader)	Electronics Technician		UH
JinChun Yuan			Research Associate		UH 
Craig Nosse   			Scientist			UH
Molly Lucas			Graduate Student		UH-M. Atkinson

	
JGOFS group:
	
Dale Hebel			Chief Scientist	(co-PI JGOFS)	UH
David Pence			Research Associate		UH
Terry Houlihan (Watch Leader)	Research Associate		UH
Louie Tupas			Scientist(co-PI JGOFS)		UH
Dan Sadler			Graduate Student		UH-T. Li

	
Ancillary projects:
		
Chuck Stump			Scientist			UW-S. Emerson
Karen Selph			Graduate Student		UH-M. Landry
Gretchen Rollwagen		Graduate Student		UH-M. Landry
Bob Miller			Graduate Student		UH-M. Landry
Sue Vink			Scientist			UH-C.Measures
Ricardo Letelier		Scientist			OSU
Mai Lopez			Scientist			SIO-M. Huntley
		
	
STAG:
		
Steve Poulos			Electronic Technician		UH-UMC
Luigi Pozzi			Deck Technician			UH-UMC

		
		

Itinerary (approximate local time):
----------------------------------

Tuesday, 4 April 
	0900	Departed Snug Harbor
	1150	Arrived Kahe Pt. (Sta. 1-1)
	1445	Departed Kahe
	1830	Arrived Kaena Pt. (Sta 1-2)
	2045	Departed Kaena Pt.
Wednesday, 5 April
	0300	Arrived Aloha (Sta. 2) trap deployment site 
	0500	Completed sediment trap deployment
	0600	Arrived Aloha (center of circle), WOCE deep cast
	1100	Began 36 hr burst sampling
	1230	Plankton net tow	
Thursday, 6 April
        0100	Plankton net tow
	0330	Commenced Go-Flo cast
	0545	Deployed primary productivity array
        1300	Plankton net tow, PNF, TSRB
	1900	Retrieved primary productivity array
        2000	Pumped tanks
        2100	Discovered compromised nutrient samples
        2200	Plankton net tow
Friday, 7 April
       0030 	Completed "burst" sampling
       0100	Plankton net tow
       0400 	Began ancillary work and repeated JGOFS and WOCE nutrient
		collections
       1500	Began Optical Mooring Buoy deployment
       2000	Completed triangulation
       2130	Began equipment recovery operations
Saturday, 8 April
       0600	Completed recovery operation
       0900	Began sediment trap recovery
       1300	Transit station ALOHA
       1630	TSRB
       1700	Deployed OPC
Sunday, 9 April
       0600	Recovered OPC	
       0730	Arrived Snug Harbor 
       1000	Offloaded
	



Narrative:
---------

HOT 62 was conducted 4-9 April, 1995  aboard the R/V Moana Wave with
Capt. Hayes as Master.  All over-the-side operations were completed and
all samples collected although the nutrient samples collected at Kahe
and Kaena are most likely compromised.  Ricardo Letelier (OSU) deployed
a moored optical buoy (MOB), followed by a dragging attempt to recover
our lost equipment.  The optical plankton counter (OPC) was deployed on
the return leg.

We departed Snug Harbor 4 April 1995 at 0900 hrs.  We were scheduled to
leave at 0800 hrs but were delayed one hour while critical sample
documentation and essential chemicals were delivered from UH.  Once
outside the mile buoy the First Mate (John Stahl) conducted the routine
fire and abandon ship drills.  A short science meeting followed to
delineate the cruise plan, watches, core work and ancillary projects.
At Kahe we conducted a weight cast to 500m followed by a PNF and TSRB
(tethered spectraradiometer buoy) cast and finally 1000 m CTD cast.
All equipment operated properly with the exception of the TSRB.  The
problem was subsequentially corrected.  After all samples were
collected we departed Kahe for Kaena Point. Upon arrival at station 6
(Kaena Point) a CTD cast to 2498 db was conducted with 15 bottles
tripped for DO, Chla, and LLN samples.

Following the Kaena Point station we steamed to station ALOHA.  Once on
station we deployed the sediment traps and initiated CTD operations.
The JGOFS spectraradiometer was slated for deployment on the trap line,
however, the correct buoyancy components were not available and
therefore the instrument was not deployed.  Routine sampling ensued
through the 36 hr brust sampling period until it was recognized (~2000
hrs 4 April 95), that the freezer top, where the nutrient samples were
stored, had been left open.  Upon closer examination it was determined
that all samples were thawed and, at this point, it was not clear if
they had ever been frozen.  Due to time constraints we were unable to
resample the Kahe Point and Kaena Point stations, therefore, these
samples were not discarded.  However, we were able to resample the
standard JGOFS and WOCE shallow and deep nutrient samples.  Subsequent
measurements of the chest freezer temperature indicated that it could
not attain a temperature low enough to freeze seawater samples.  The
day following the incident the temperature was 0.5   C and by the end
of the cruise had climbed to 10 C.

With the completion of the core and ancillary work at station ALOHA we
steamed  NNE (~050  T) just outside the ALOHA circle and surveyed the
bottom topography for the proper bathymetry and relief for the
deployment of the MOB.  Having found the correct locale and being
careful to avoid phone cables we backtracked the required distance to
ascertain the placement of the mooring in the correct location.
Following deployment (~2 hrs; 22 50.87 N, 157  55.55 W anchor away
location) we fixed the position by triangulation before departing to
the lost equipment postion.  Although a position was derived (?N, ?W),
one of the 3 points was less than ideal resulting in a relatively
imprecise, but hopefully, reasonably accurate determination.

With the realization that the core nutrient samples would have to be
resampled the equipment recovery operation was tentatively scrubbed.
However, expedient use of CTD sampling depths and time resulted in the
collection of a full sample set within a time frame which still
permitted an equipment recovery attempt.  It has become a realization
that no extra time is available on our HOT cruises.  This is especially
true with upcoming cruises and therefore the current, yet limited, time
frame was viewed as an opportunity to learn and better yet possibily
succeed at a most improbable task.  One of the two goals was achieved.
We did learn that the configured dredging array would remain on the
bottom when underway and we did learn that the terminal grapnel hook
was effective.  We managed to hook something on the bottom that
effectively protracted the operation for a period of hours over that
initially intended.  The substance of the connection was so great that
it literally pulled the ship backwards allowing winch speeds of only
0-10 m/min with associate tensions of 10-14K lbs with the main engines
decluthed.  PDR recordings revealed a varied bottom releif grading from
flat to a ridge-like structure where contact was made.  This was in a
vicinity which was past the most probable point of contact for the lost
equipment.

After the unsuccessful recovery attempt we steamed to the vicinity of
the sediment traps which were located and recovered without incident.
Following the recovery we conducted the AC-3 test cast and collected
samples for <202 um suspended matter (TSM), outside the circle
confines.  The data of the AC-3 test cast which profiled to 2000 m have
not been processed but the initial response from Jefrey was
unfavorable.  The deployment of the OPC was scheduled to begin at the
trap recovery site and proceed to just outside Honolulu Harbor.
However, a request from the scientist in charge (Mai Lopez), altered
the plan to return to station ALOHA, transit the diameter of the circle
along 158 then change course for Snug Harbor.  The OPC was towed
between 8-8.5 kts and retrieved south of Barbers Point.  We arrived at
Snug Harbor 9 April @ 0730 hrs and since we were the next science group
to use the ship offloaded only the handcarried equipment, samples and
other essential equipment by 1000 hrs.


	    
Weather:
--------

The weather was mostly overcast with moderate to high winds and low to
moderate seas.  Below is listed the cruise log bridge descriptions and
the various values represent the range for that day.  Under wind, sea
and swell there will be two designations, the first is the direction
(in degrees), the second for wind is in kts, for sea in Beauford force,
for swell in feet, and clouds in tenths.

		
Day	      Date	Wind		Sea		Swell		Clouds
	
	
Tuesday	      4 April	045-055, 20-28	045-055, 3-4	000-030, 3-8	3-8
Wednesday     5 April	050-070, 24-28	050-070, 3-4	030-060, 6-8	7-10
Thursday      6 April	050-070, 14-22	050-070, 2-3	060, 4-8	8-10
Friday	      7 April	070-115, 15-25	070-115, 3-4	070-090, 5-6	3-10
Saturday      8 April	110-165, 5-20	110-165, 1-3	090-130, 3-6	3-7
Sunday*	      9 April	150, 7		150,1		130, 2-3	2-7

	*Only two entries




Equipment and methods:
----------------------

All standard equipment used on HOT 62  functioned properly.  No
equipment was lost, however, one primary productivity sample bottle at
125 m (3L1) was lost.  The initial deployment of the TSRB was
problematic but was subsequentially repaired.  One of the tangs on the
terminal grapnel was bent out during the dragging operation.  This was
a piece of STAG equipment.



Sub component programs:
-----------------------

Investigator:				Project:
-------------				--------

Telu Yuan-Hui Li (UH)			DIC, pH, Alk., pCO2
Bob Bidigare (UH)			HPLC pigments
Michael Landry (UH)			Zooplankton dynamics


Ancillary programs:
-------------------

Investigator:				Project:
-------------				--------
Chris Measures				Trace metal studies
Steve Emerson				Oxygen/Argon/Helium measurements
Charles Keeling (SIO)			CO2 dynamics and inter calibration
Paul Quay (UW)				DIC and 13C
Hans Thierstein (Zurich) 		Calcareous plankton dynamics
George Luther (UD)			Iodine speciation


Students:	
---------
Bob Miller				Zooplankton sampling training
Gretchen Rollwagen			Zooplankton sampling training


Others:
-------

Ricardo Letelier (OSU)			Optical oceanography
Mark Huntley/Mai Lopez			Optical plankton counting