III. METHODS AND PROCEDURES 



A. Instrumentation and Data Collection. 



Serial-depth temperature, salinity, and dissolved oxygen data 

 were obtained by standard Nansen cast techniques. Paired protected 

 and unprotected deep sea reversing thermometers were placed on the 

 Nansen bottles for in situ temperatures. Water samples were drawn 

 from the Nansen bottles for chemical analyses. 



On the January survey, water samples for dissolved oxygen, phosphate, 

 and silicate analyses were drawn at the stations located within a 

 50-mile radius of Point Arguello. The phosphate and silicate samples 

 were frozen for later analysis at NAVOCEANO. 



On both surveys, temperature measurements were made periodically 

 with mechanical BT's. BT data were forwarded to the National Oceanographic 

 Data Center (NODC) for processing. 



The bottom sediment samples were obtained by means of a Kullenberg 

 corer and an orange peel sampler at the stations shown in Figures 

 2 and 3. The cores were protected against desiccation by coating 

 the core liners in a specially constructed wax bath. 



Surface plankton hauls (Figs. 2 and 3) were obtained with a half- 

 meter net, mesh size #0, as the ship drifted on station. For vertical 

 hauls, the same net was lowered to 200 meters and retrieved. The 

 samples were preserved and shipped to the NAVOCEANO biological laboratory 

 for analysis. 



Parachute current drogues, with the parachute at either 50, 

 300, 500, or 1,000 feet (15, 90, 150, or 305 meters), were released 

 and tracked. Positioning of the drogues on the January survey was 

 by radar range and bearing. Because of new requirements on the 

 ship's time, drogue observations were abridged. Drogue positions 

 were determined chiefly by Lorac on the November-December survey, 

 but, since Lorac coverage did not extend north of Point Arguello, 

 radar was used for some positions. 



B. Methods of Analyses and Disposition of Data. 



Reversing thermometer temperatures were read to +0.01"'C and corrected 

 by standard methods. 



Salinities were analyzed aboard ship with a conductive salinity 

 bridge during the January survey and an inductive salinometer during 

 the November-December survey. 



Dissolved oxygen concentrations were determined aboard ship using 

 a modified Winkler titration method. 



