Townsend Cromwell , cruise 5: 

 June 15 to July 5, 1964 



Robert P. Brown - HL - Field Party Chief 



Howard Adrian - HL 



Melvin E. Kau - HL 



Michael R. Marcotte - HL 



Stephen M. Skolnick - HL 



Dayle N. Husted - Smithsonian Institution 



Warren King - Smithsonian Institution 

 Townsend Cromwell , cruise 6: 

 July 13 to August 1, 1964 



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



Howard Adrian - HL 



Claude E. Allen - HL 



Arthur M. Bauckham, Jr. - HL 



Paul M. Shiota - HL 



Dayle N. Husted - Smithsonian Institution 



Warren King - Smithsonian Institution 



H. W. Tinkelenberg - Massachusetts Institute 

 of Technology 



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. 



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. 



Meteorological 



Rain measurements as well as standard 

 weather observations were taken tour times 

 daily. Radiation from sun and sky was meas- 

 ured and recorded daily with an Eppleyl' pyra- 

 nometer. These observations were supple- 

 mented by daily color photographs of clouds. 



— All data not presented in this report are on 

 file at the Bureau of Commercial Fisheries Bio- 

 logical Laboratory, Honolulu 96812. 



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 on cruise 4 and a Roberts meter on 

 cruise 5, both suspended from the ship. The 

 ship was drifting relative to a parachute drogue 

 placed at a depth of 1,200 m. On cruise 6, H. W. 

 Tinkelenberg conducted sound-ranging tests 

 using subsurface floats which imploded in the 

 sound channel after a period of time. Results 

 of these tests can be obtained from H. Stommel, 

 Massachusetts Institute of Technology, Cam- 

 bridge, Mass. 02139. 



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. Oxygen concentrations 

 were determined by the modified Winkler 

 method (Thompson and Robinson, 1939). Inor- 

 ganic PO4-P was determined by the procedure 

 of Robinson and Thompson (1948) as modified 

 at the University of Washington. All thermom- 

 eters had been calibrated at HL since April 

 1962. The reported temperatures are esti- 

 mated to be accurate to +0.02° C. Application 

 of corrections to protected and unprotected 

 thermometer readings 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 written at HL. Depths were deter- 

 mined 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 



2/ 



— Trade names referred to in this publication 



do not imply endorsement of commercial products. 



