HOT-13: Chief Scientist Report

Chief Scientist: C. WINN

HOT-13 Cruise Report
R/V Moana Wave
3-7 Jan. 1990 



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

Darryl Jarman		WOCE
Chris Winn		GOFS
Ricardo Letelier	GOFS
Dale Hebel		GOFS
Stewart Reid		WOCE
Jef Snyder		WOCE
Georgia Tien		GOFS
Ken Shultis		WOCE
Marc Rosen		WOCE/GOFS
Chris Sabine		GOFS
Pierre Flament		WOCE
Robert Knox		WOCE
Dave Wilbur		U.W. Oxygen
Chuck Stump		U.W. Oxygen
Robert Chen		Scripps
Eric Firing		WOCE
Shoeb Javed		WOCE



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

3 Jan.
  0800 Depart Snug Harbor
  1100 Arrive Kahe Pt
  1400 Depart Kahe Pt
4 Jan.
  0000 Arrive HOT-site: deploy sediment traps
  0300 Commence water sampling
       WOCE deep casts
  1300 Light cast
  1500 Commence CTD sampling
       including:
5 Jan.
  0300 Primary productivity cast
  0500 Deploy in situ primary production array
  0600 Continue CTD profiling
6 Jan.
  0300 Cease continuous CTD sampling
  0330 Locate traps
  0800 GOFS cast
  1100 ADCP cast
  1500 GOFS cast
  1900 ADCP cast
  2300 GOFS cast
7 Jan.
  0200 10 m cast
  1400 Recover traps
  2000 Arrive Snug Harbor



Narrative:
----------

HOT-13 departed Snug Harbor at 0800 on 3 January 1990, aboard the R/V
Moana Wave. Approximately 3 hours were spent on station at Kahe Point
on both the transit to ALOHA and the return to Snug Harbor, and about
72 hours were spent at Station ALOHA. Because of problems with the CTD
deck box, no CTD data were collected at Kahe Point on the outbound leg.
The station was reoccupied on our return transit to Snug Harbor.


WOCE & JGOFS Sampling

All WOCE and JGOFS chemical sampling was completed on HOT-13.


CTD and XBT Operations

In general, CTD operations were successful on this cruise. However,
problems with the deck box prevented the collection of CTD data at Kahe
Point on the outbound transit, and oxygen sensor problems prevented the
collection of continuous oxygen profiles on most of the CTD casts
collected at Station ALOHA. The Kahe Point data was collected on the
return leg. In spite of sensor problems, CTD oxygen sensor data was
collected at Kahe Point and on three casts, including the WOCE deep
cast, at Station ALOHA. XBTs were deployed on the return leg to Snug
Harbor.


Primary Production and Sediment Trap Measurements

Primary production and particle flux measurements were made at Station
ALOHA. Primary production was measured in situ for 12 hours using the
free-floating array and 24-hour incubations were conducted using the
on-deck incubator system. Several bottles from the upper three
incubation depths were lost during the recovery of the in situ array
when the array drifted under the ship. However, some replicate samples
incubated at each of these depths were recovered. The sediment trap
samples were collected without problems.


Optical Measurements

Surface irradiance measurements were collected with both the 2 pi and
cosine collectors. Underwater PAR profiles were collected with the
submersible 4 pi collector.


ADCP Measurements

Current measurements were made with the hull-mounted ADCP. In addition,
test casts were conducted with an ADCP attached to the 12-place
rosette. Several ADCP calibration runs were made in the vicinity of the
HOT site.


Ancillary projects

In addition to the regular JGOFS sampling, samples for dissolved gases
were collected for Charles Keeling of Scripps Institution of
Oceanography and for Steve Emerson and Paul Quay of University of
Washington. Samples for dissolved organic compounds were collected by
Robert Chen of the Scripps Institution of Oceanography.