HOT-43: Chief Scientist Report
Chief Scientist: D. HEBEL
HOT 43 Cruise Report
R/V Kila
15-17 Dec. 1992
Personnel List:
---------------
Dale Hebel Chief Scientist UH
WOCE group:
No representatives
JGOFS group:
John Christian Graduate Student UH
Terry Houlihan Technician UH
Dave Karl Principle Investigator UH
Dan Sadler Graduate Student UH
Ancillary projects
Emerson's O2 project:
Chuck Stump Technician UW
Dick Young (squid influx study):
John Bower Graduate Student UH
Campbell's Picoplankton project:
No representatives
STAG:
No representatives
Itinerary (approximate local time):
-----------------------------------
Tuesday, 15 Dec.
0700 Departed Snug Harbor
2030 Arrived ALOHA
2100 Commenced hydrocasts
Wednesday, 16 Dec.
1700 Completed hydrocasts
1730 Departed ALOHA
Thrusday, 17 Dec.
0730 Arrived Snug Harbor
Narrative:
----------
HOT 43 was conducted aboard the R/V Kila (Ross Barnes master) with the
cruise duration and work schedule similar to HOT 42. However, we did
not stop or collect samples at Kahe Pt. during HOT 43 as was done on
HOT 42. Nine hydrocasts (less than or equal to 250 m) were completed
at station ALOHA with all but two having Niskin bottles attached to the
kevlar line. The two hydrocasts without bottles were used to determine
if the salinity spiking we observed on HOT 42 with the Seacat CTD
profiler was due to the start-stop deployment method resulting from
hanging and removing the bottles. During these casts the profiler was
lowered and raised without interruption. In addition to the hydrocasts
we conducted limited PNF casts and did not deploy the sediment traps
or primary productivity arrays.
Although the cruise time frame was very short we were able to collect
most of our core water column samples at ALOHA. Of the 7 water bottle
casts one was to 50 m for C. Stump's respiration experiment and the
remainder were 12 bottle casts to 250 m or less where samples for both
UW and UH were collected. Samples collected included DO, DOC, Chl a
(f), inorg. nutrients, LLP, NOx, pH, Alk, refrig'd Si, UW DO, UW
Oxy/Ar, Keeling & Quay DIC, PPO4, PC, PN, HPLC pigments, bacteria, flow
cytometry samples, and salts.
Weather:
--------
The weather was unsettled at station ALOHA with northwest and easterly
winds ranging from 10-15 kts with mostly cloudy skies. The sea state
ranged from 3-5 deteriorating over the day with the swell ranging from
3-4 m.
Equipment and methods:
----------------------
All equipment used on HOT 43 was identical to HOT 42. We used our DSE
winch with kevlar line and twelve 10 and 12 l General Oceanic Niskin
bottles. Bottles were manually attached and removed for each cast over
a depth interval of 250 m. At the terminal end of the Kevlar line was
an SBE- 19 Seacat internally recording CTD with transmissometer. The
Seacat was suspended 9 m below the 250 m mark. Niskin bottles were
hung at either 10 m or 5 m increments over the 250 m depth range as
recorded on our cast data sheets.
Ancillary programs:
-------------------
Investigator: Project:
------------- --------
Steve Emerson (UW) O2, respiration, and DO
intercalibration
Charles Keeling (SIO) CO2 dynamics and inter calibration
Lisa Campbell (UH) Picoplankton studies
Paul Quay (UW) Isotopic DIC studies
Students:
---------
John Bower Squid influx studies
Others:
-------
none
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