thermometers are used on each Nansen bottle. At 

 least, five bottles from 200 to 1,500 meters have an 

 unprotected thermometer in conjunction with the 

 protected thermometers for the thermometric de- 

 termination of sampling depths. In situ tem- 

 peratures are determined by the average of the 

 corrected readings of the protected thermometers. 

 The maximum difference tolerated between the two 

 readings is ±0.040 °C. 



3. Samples of water are drawn from each Nan- 

 sen bottle for the determination of salinity aboard 

 ship. Duplicate samples are drawn from the top 

 and bottom Nansen bottle in each cast and deliv- 

 ered to the U.S. Coast Guard Oceanographic Unit 

 for quality control comparisons. The salinities are 

 determined aboard ship by Model 6220 inductive 

 salinometers manufactured by the Bisset-Berman 

 Corp. These instruments have a probable accuracy, 

 as stated by the manufacturer, of ±0.003% o . 



DATA TREATMENT 



The data for each station, including tempera- 

 ture, salinity, and depth, are encoded and trans- 

 mitted to U.S. Coast Guard Oceanographic Unit, 

 "Washington, D.C., via radio teletype for real-time 

 data processing and quality control. The tempera- 

 ture data are transmitted immediately after the 

 observations are made while the salinities are usu- 

 ally transmitted within 3 days of observation. The 

 U.S. Coast Guard Oceanographic Unit processes 

 these data with a Digital Equipment Corp. PDP-5 

 computer. Nansen cast temperatures are corrected 

 at U.S. Coast Guard Oceanographic Unit and 

 transmitted to the Fleet Numerical Weather Fa- 

 cility, Monterey, California, within 12 hours of ob- 

 servation for use in forecasting oceanographic 

 conditions. 



Values of density (o- t ) and dynamic heights 

 based on the 1,000 decibar level are determined 

 at each sample depth. The U.S. Coast Guard 

 Oceanographic Unit computes the dynamic heights 

 of the various levels, summing both the observed 

 specific volume anomaly values and the interpo- 

 lated standard depth values. The determination 

 of dynamic heights in shallow water is performed 

 in the manner described by Helland-Hansen 

 (1934). This method assumes that level isoteric 

 surfaces extend from the water-sediment inter- 

 face, on the continental slope, into the bottom to 

 a point directly below the next station. This 

 allows the extension of the pressure surfaces, 



related to the 1,000 decibar level of no assumed 

 motion, above the shelf as far as the Coast. 



Volume flow computations are accomplished at 

 U.S. Coast Guard Oceanographic Unit by a com- 

 puter program specifically written to provide 

 transport information through vertical property 

 sections (Kollmeyer, et al., 1966). The program 

 computes volume flow information through sole- 

 noids which subdivide a property section into small 

 rectangles. The solenoids are bounded by the data 

 obtained from adjacent stations at the various 

 standard depths. The volume flow information is 

 calculated using the following equations : 



V=V m XA 



where 



V m = 



10(D A -D B ) 



(1) 



(2) 

 (3) 



fL 



A=dXL 

 V= volume flow 

 U m =mean water velocity within 



the solenoid 

 .4= Area of solenoid, bounded 

 by station locations and 

 standard depth intervals 

 (D A —D B )= Difference in mean dy- 

 namic height values be- 

 tween adjacent stations, 

 based on the 1,000 deci- 

 bar level, at a point be- 

 tween the upper and 

 lower standard depth 

 values bounding the 

 solenoid. 

 /=Coriolis parameter=2Q 

 sin <(> 

 where fi= angular velocity 

 of earth 

 <£= latitude 

 L=Distance between adjacent 



stations 

 d= Vertical distance between 

 the standard depth 

 values bounding the 

 solenoid. 

 Combining equations (1), (2), and (3); 



Tt \0(D A -D B )d 

 / 



The volume flow calculations are now independent 

 of the distance between stations. This allows sim- 



(4) 



