Townsend Cromwell cruise 2: 

 March 16 to April 5, 1964 



Robert P. Brown - HL - Field Party Chief 



David W. K. Au - HL 



Melvin E. Kau - HL 



Rodney Klmura - HL 



Lloyd T. Watarai - HL 



Warren King - Smithsonian Institution 



Robert Sundell - Smithsonian Institution 

 Townsend Cromwell cruise 3: 

 April 12 to May 4, 1964 



Lloyd T. Watarai - HL - Field Party Chief 

 (4/12-4/18) 



David W. K. Au - HL - Field Party Chief 

 (4/19-5/4) 



Howard Adrian - HL 



Joseph R. Harada - HL 



Henry M. Kishinami - HL 



Douglas Edsall - National Oceanographic 

 Data Center 



David Bratley - Smithsonian Institution 



Warren King - Smithsonian Institution 



OBSERVATIONS - 



In addition to the regular Nansen and BT 

 casts shown in figure 1. BT casts were made 

 at 18.5-km. (10-nautical-mile) intervals for 

 studies of variability between stations 19 and 

 21, 26 and 28, and 35 and 37, except for cruise 

 1, where one series was between stations 31 

 and 33 instead of stations 19 and 21. 



To supplement the physical oceanographic 

 data presented in this report, additional infor- 

 mation of the following types was obtained. 



Biological 



A l/2-hour surface plankton tow was taken 

 daily at 2000 hours with a 1-m. net. Flyingfish 

 which stranded themselves on deck were col- 

 lected daily. Regular observations of fish 

 schools, sea mammals, and birds were supple- 

 mented by more detailed bird counts by ob- 

 servers from the Smithsonian Institution on 

 Cromwell cruises 2 and 3. 



Meteorological 



Rain measurements as well as standard 

 weather observations were taken four times 



— All data not presented in this report are on 

 file at the Bureau of Commercial Fisheries Bio- 

 logical Laboratory, Honolulu 96812. 



daily. Radiation from sun and sky was meas- 

 ured and recorded daily with an Eppley pyra- 

 nometer. These observations were supple- 

 mented by daily color photographs of clouds. 



Current 



Ten plastic-enclosed drift cards, described 

 by Barkley, Ito, and Brown (1964), were re- 

 leased at each BT cast. Current-measuring 

 techniques were tested with an Ekman current 

 meter, suspended from the ship. The ship was 

 drifting relative to a parachute drogue placed 

 at a depth of 1,200 m. 



PREPARATION OF DATA 



Standard oceanographic procedures were 

 employed in the preparation of the data for this 

 report. Salinity determinations were made on 

 the University of Washington salinity bridge 

 (Paquette, 1958). Duplicate determinations 

 were made with an induction salinometer. When 

 values differed more than 0.02 °/oo, the salinity 

 was redetermined on the U.W. salinity bridge, 

 and the mean of the salinity bridge determina- 

 tions was reported. All thermometers had been 

 calibrated at HL since April 1962. The re- 

 ported temperatures are estimated to be ac- 

 curate to+0.02°C. Application of corrections to 

 protected and unprotected thermometer read- 

 ings and computations of thermometric depths 

 and L-Z values were performed with an IBM 

 7040 digital computer^' at the University of 

 Hawaii Computing Center with a program writ- 

 ten at HL. Depths were determined by the use 

 of values from the L-Z curve for the actual 

 depth. This procedure gave depth estimated to 

 be within +10 m. down to 1,000 m. and within 

 + 1 percent below 1,000 m. 



Sigma-t, specific volume anomaly, and the 

 dynamic height were computed on the IBM 7040 

 computer by the program prepared at HL and 

 based on equations given by LaFond (1951). 

 The computer also was used to interpolate all 

 properties at standard depths by means of a 

 subroutine furnished by the University of Wash- 

 ington Oceanography Department and based on 

 the interpolation method outlined by Rattray 

 (1962). 



In the region of study, a sharp thermocline 

 generally separates a surface mixed layer from 



2/ ~^ 



— Trade names referred to in this publication 



do not imply endorsement of commercial products. 



