3) Determine meridional contributions to eddy transports of 

 momentum, heat, and energy and interactions of eddies with 

 the mean circulation; 



4) Study mechanisms that relate to production, transformation, 

 and dissipation of eddy energy; 



5 ) Develop and test numerical models of mesoscale and gen- 

 eral oceanic circulation, including mesoscale eddies. These mod- 

 els are especially useful because of their importance in fore- 

 casting, process investigation, and coupling to atmospheric 

 models. 



The detailed design of the experiment requires quantitative 

 analysis of existing data, formulation of statistical descriptors 

 for the various fields, error estimation through measurement 

 theory, and further numerical modelling studies. Major compo- 

 nents of the proposed program are: 



1 ) Current and temperature measurements from moored sta- 

 tions (fig. 4). 



2) Density surveys from ships and by other means (such as 

 inverted echo sounders), and 



3 ) Observations of SOFAR floats. 



Soviet and U.S. scientists will make current and tempera- 

 ture measurements from moored stations. Soviet scientists will 

 have the main responsibility for density surveys and U.S. scien- 

 tists for the SOFAR Float Program. Scientists from both coun- 

 tries will participate in the theoretical studies. A preliminary 

 schedule of activities is given in table 1. 



U.S. Pre-POLYMODE Activities. Several exploratory ef- 

 forts are underway in the area identified for POLYMODE, 

 somewhat to the east of the MODE-I region. One effort is to 

 obtain XBT observations from ships of opportunity crossing the 

 North Atlantic (fig. 5). A pilot current-meter array (Array-1) 

 for POLYMODE-O was set in July-August 1974 to obtain data 

 on low-frequency fluctuations east of the Bermuda Rise along 

 55-60°W. Array-1 is scheduled to be recovered in April 1975. 

 Five SOFAR floats that were launched during MODE-1 are 

 still being tracked and several new floats have been launched to 

 test a new signaling scheme. 



MODE Bibliography 



Baker, D. James, Jr., 1972: The fused quartz deep-sea pressure 

 gauge II, Results of high pressure and deep-sea tests, 

 March-April 1972, Harvard Reps. Meteorol. Oceanogr. 

 No. 5. 



Baker, D. James, Jr., 1973: The fused quartz deep-sea pressure 

 gauge III, Measurements of pressure fluctuations in the 

 MODE-I area, August-December 1972, and high pressure 

 calibration. Harvard Reps. Meteorol. Oceanogr. No. 6. 



Baker, D. James, Jr.. Richard B. Wearn, Jr., and Winfield Hill, 

 1973: Pressure and temperature measurements at the 

 bottom of the Sargasso Sea, Nature 245( 141 ) :25-26, 

 (MODE Contribution No. 6). 



Bennett, David, and J. H. Filloux, 1975: lUGG Ouasidynam- 

 ical Report — Magnetotelluric, deep electrical sounding and 

 resistivity, J. Geophys. Res. 1 3(3 ): 197-202, (MODE 

 Contribution No. 30). 



Figure 4. — Proposed POLYMODE mooring pattern (top) and 

 density survey pattern (bottom). U-shaped contour in both 

 figures delineates areas of rough and smooth bottom topography. 

 In bottom diagram, dashed lines enclose mooring pattern 

 of top diagram, solid lines indicate density survey stations 

 and central area. 



Bretherton, Francis P., and Michael Karweit, 1974: Midocean 

 mesoscale modelling. Proceedings of Symposium on Nu- 

 merical Models of Ocean Circulation, October 17-20, 

 1972, Durham, N.H., in press, (MODE Contribution No. 

 23). 



Brown, Wendell, Walter Munk, Frad Snodgrass, Harold Mof- 

 jeld, and Bernard Zetler, 1975: MODE bottom experi- 

 ment, J. Phys. Oceanogr. 5(l):75-85, (MODE Contribu- 

 tion No. 15). 



Bruce, J. G., and Eric Firing, 1974: Temperature measure- 

 ments in the upper 10 m with modified expendable bathy- 

 thermograph probes, /. Geophys. Res. 79(27) :41 10-41 1 1, 

 (MODE Contribution No. 21). 



14 



