in the upper layers. One hundred fourteen stations were occupied, most 

 of them with two lowerings. The heading data for these stations are 

 listed in Appendix I. These headers differ from 1971 only in the pre- 

 sence of SORD in Column 69 and the addition of a negative exponential 

 description for ice concentration described in Appendix I. 



B. TECHNIQUES 



The STD was a Bissett-Berman Model 9006 supplied by the 

 Arctic Submarine Laboratory. It had a 200-foot depth scale, a 30-35 o/oo 

 salinity scale, and a -2 to +10 C temperature scale. There were more 

 expanded salinity and temperature scales but they were used only in a 

 few cases. The instrument was of the pen-writing type; on the expanded 

 depth scale it produced incomparably better records than in 1971. No 

 electrical noise was experienced, possibly due to the use of a line filter 

 in the a.c. power supply. It was not necessary to use the Beckman RS5. 



Unfortunately, the temperature compensator for salinity was no 

 better than before. The characteristic time constant was measured and 

 found to have a dominant constant of 2.0 seconds and one of 17. 6 seconds 

 involving a smaller heat capacity. To alleviate the problem of spurious 

 salinity spikes as much as possible, lowering was done at the slowest 

 speed of the winch, 0.09 m/sec. This was about seven times slower than 

 in 1971 but still was not slow enough to eliminate spikes when the tem- 

 perature gradients were sharp. For this year, the oscillations of salinity 

 were traced faithfully with the digitizer because we expected eventually 

 to be able to correct the salinities and use the resulting densities in a 

 study of mixing processes near the ice margin. This correction has not 

 been carried out as yet. 



We went prepared with a 270-ohm shunt for the conductivity 

 cell which was the value which was used in 1971. This did not permit 

 the entire salinity range to be covered because now there was only one 

 wide-range scale as contrasted with six ranging from 30 to 41.5 o/oo 

 after the recorder was shunted in 1971. This was quickly discovered 

 and a 400-ohm shunt was constructed in the field and calibrated as 

 before. Most of the 114 stations were done in two lowerings as in the 

 latter part of MIZPAC 71 . 



The STD was standardized as in 1971 at nearly every station. 

 At most of the stations surface salinities and temperatures were taken by 

 way of a bucket. Surface salinities are often much lower and tempera- 

 tures higher than the first reading of the STD. This is to be expected 

 because the uppermost reading of the STD is about one meter beneath the 

 surface skin. 



A 6 



