UNITED STATES DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE SERVICE Bureau of Commercial Fisheries P. O. Box 3830, Honolulu, Hawaii 96812 PLAN FOR TOWNSEND CROMWELL, CRUISE 2 I. OBJECTIVE: The Trade Wind Zone Investigation is an oceanographic experiment to verify a qualitative circulation model and to obtain those data which are necessary to develop a model to explain the changes in the distribution of properties (temperature, salinity, etc.) in the sea in terms of seasonal changes in processes (net heat exchange and water exchange across the sea surface, wind stress, and effects of water motion). The experiment consists of three phases: the design and planning phase to ensure that the data to be obtained are significant in terms of the problems to be tackled; the field phase, a four-ship, 24 months operation to obtain observations of the three-dimensional time-sequence dis- distribution of properties in the North Pacific trade wind zone; the analysis and evaluation phase. As part of the design and planning phase of the investigation a sequence of cruises to take place at 30-day intervals using one ship has been planned to test and evaluate the sampling procedures and processing techniques. Cruise 2 of the Townsend Cromwell is the second in this series of cruises. II. CRUISE PERIOD: March 16 to April 4, 1964. III. AREA OF OPERATION: Central North Pacific bounded by latitudes 10° N., 27° N. and longitudes 148° W., 158° W. (See attached chart for cruise track). IV. MISSIONS: A. OCEANOGRAPHIC 1. On each of the 42 oceanographic stations temperatures and salinities will be obtained at the following depths: 0, 10 (50), 75, 100, 125, 150, 175, 200, 225, 250, 275, 300, 400, 500, 600, 800, 1000, 1200, and 1500 meters.