White, W. B. 1975: Secular variability in the large-scale 

 baroclinic transport of the North Pacific from 1950- 

 1970, /. Mar. Res. 33( 1 ) :141-155. 



White, W. B. and N. E. Clark. 1975: On the development of 

 blocking ridge activity over the Central North Pacific, 

 /. Atmos. Sci. 32(3):489-502. 



Wyrtki, K. 1975: Fluctuations of the dynamic topography in 

 the Pacific Ocean, /. Phys. Oceanog. 5(3) :450-459. 



Wyrtki, K. 1975: El Niiio — The dynamic response of the 

 Equatorial Pacific Ocean to atmospheric forcing, /. Phys. 

 Oceanog. 5(4):572-584. 



Wyrtki, K. and G. Meyers. 1975: The Trade Wind field over 

 the Pacific Ocean, Part I, the mean field and the mean 

 annual variations, Univ. Hawaii Ref. HIG-75-1. 



Wyrtki, K. and G. Meyers. 1975: The Trade Wind field over 

 the Pacific Ocean, Part IF, Bimonthly fields of wind stress: 

 1950 to 1972, Univ. Hawaii Ref. HIG-75-2. 



Wyrtki, K., E. Stroup, W. Patzert, R. Williams, and W. Quinn. 

 1976: Predicting and observing El Nifio, Science 191 

 (4225): 343-346. 



NORPAX Technical and Data Reports 



Maresca, J. W., Jr. and J. R. Barnum. 1975: Measurement of 

 sea scatter and buoy tracks at long ranges by high-resolu- 

 tion OTH-B radar. Final Rep. SRI Project 3071, Stanford 

 Research Institute, Menlo Park, CA 94025, 70 pp. 



Sessions, M. H., W. R. Bryan, and T. P. Bamett. 1974: AXBT 

 calibration and operation for NORPAX POLE Experi- 

 ment, Scripps Institution of Oceanography, SIO Ref. Series 

 74-31, 27 pp. 



Stidd, C. K. 1974: Ship drift components: means and standard 

 deviations, SIO Ref. Series 74-33, 57 pp. 



Teague, C. C. 1975: In-situ decametric radar observations of 

 ocean-wave directional spectra during the 1974 NORPAX 

 "Pole" experiment. Final Report, Stanford Electronics 

 Laboratory, Stanford Univ., Stanford, Calif., Tech. Rep. 

 No. 3615-2, 34 pp. 



International Southern Ocean Studies (ISOS) 



ISOS is concerned with understanding the long-term, large- 

 scale variability of dynamical processes in the Southern Ocean. 

 It consists of a series of experiments to determine global atmos- 

 pheric and oceanic circulation and their interaction. The project 

 has focused on the dynamics of the Antarctic Circumpolar 

 Current, the First Dynamic Response and Kinematics Experiment 

 (F DRAKE), but studies have been made of bottom-water 

 formation and the Polar Front. The long-range scientific 

 objectives of ISOS and F DRAKE cruises are to: 



1 . Identify space and time scales of the Antarctic Circumpolar 

 Current in the region of the Drake Passage and Western Scotia 

 Sea, an ultimate goal being to design a transport experiment 

 in this region; 



2. Obtain a regional description of the Drake Passage — 

 Western Scotia Sea area, including bathymetry, nutrient rela- 

 tionships, and hydrography; 



3. Improve our knowledge about the Antarctic Circumpolar 



Current in the Western Scotia Sea region — specifically to better 

 understand the synoptic features of the current in that region; 

 and 



4. Improve our knowledge of the Polar Front, to better under- 

 stand the dynamics and mixing processes of this oceanic feature. 



F DRAKE (First Dynamic Response 

 and Kinematics Experiment) 



The first field phase, F DRAKE 75, was January through 

 March 1975. During this period, current and temperature re- 

 corders were moored in Drake Passage to study time and space 

 scales in the flow though the Passage. The array of instruments 

 consisted of both long- and short-term moorings. Short-term 

 moorings were recovered at the end of each cruise and yielded 

 information about time scales of less than 20 days. Long-term 

 moorings included two tide gauges and 19 current meters and 

 yielded information regarding time scales of up to 1 year. 



Vessels participating in F DRAKE 75 were RV Conrad 

 of Lamont-Doherty Geological Observatory, RV Melville of 

 Scripps Institution of Oceanography, and ARA Islas Orcadas 

 of the Hydrographic Service of the Argentine Navy. The 

 Orcadas is participating under an agreement between the 

 National Science Foundation, the Argentine Antarctic Institute, 

 and the Argentine Naval Hydrographic Service. Observations 

 by the three ships included oceanographic stations, expendable 

 bathythermographs (XBTs), and underway oceanographic and 

 meteorological measurements (fig. 8). Special studies by the 

 Melville included occupying oceanographic stations in rela- 

 tion to the locations of moored arrays. Some moored arrays 

 were recovered during F DRAKE 75; the remainder were set 

 as year-long moorings to be recovered during F DRAKE 76. 

 During austral summer 1976 the RV Thompson, A.G.S. 

 Yelcho, and RV Professor Vize made F DRAKE cruises. 

 WOE Progress Report Volume 4 described general goals and 

 specific objectives of F DRAKE 75. 



The second field phase, F DRAKE 76, was scheduled 

 January through March 1976. The first task of F DRAKE 76 

 was recovery of the first long-term array and deployment of the 

 second year-long array (fig. 9). Recovery, deployment, and sup- 

 porting hydrographic work were accomplished during Leg I 

 of the Thompson cruise. Leg II of the Thompson cruise con- 

 sisted of a closely spaced hydrographic section parallel to the 

 array (the "DRAKE" section) and a second closely spaced 

 section perpendicular to the first (the "1976" section). During 

 Leg II, satellite-tracked drifting buoys were launched and special 

 chemical studies were included in the hyrographic work. Leg III 

 of the Thompson cruise was devoted to studying the Polar 

 Front in the region of 58°S, 64°W. Instruments used in this 

 study included CTDs, an O^ profiler, profiling current meters, 

 thermistor chains, and vertical current meters. 



The Chilean Naval vessel Yelcho was used to map the 

 temperature structure in and near the Polar Frontal Zone on 

 two cruise legs of 2 weeks duration. The first leg, which began 

 before Leg III of the Thompson cruise, was used to locate and 

 map the Polar Frontal Zone to the east of the moored arrays 

 in Drake Passage. The thermal structure was mapped using 

 XBTs and a satellite navigation receiver. Data were transmitted 

 to the Thompson via ATS transceivers aboard the vessels. This 

 made it possible for the Thompson to proceed directly to the 

 study area and concentrate on small-scale measurements. Be- 

 cause the position and configuration of the Polar Frontal Zone 



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