Table 8.— Details of current meter and mooring intercomparison carried out 

 from RV AKADEMIK VERNADSKY in October 1976 



TYPE: 



LAT: 



LONG: 



SET: 



RECOVER: 



U.S.S.R. 

 BUOY #1 

 Surface 



34° 54.3' N 

 55° 02.7' W 

 Oct. 7, 1976 

 Oct. 20, 1976 



U.S.S.R. 

 BUOY #2 

 Surface 



34° 56.9' N 

 55° 02.3' W 

 Oct. 7, 1976 

 Oct. 20, 1976 



U.S. (W.H.O.I.) 

 BUOY #581 

 Subsurface 



34° 55.6' N 

 55° 04.7' W 

 Dec. 17, 1975 

 Oct. 17, 1976 



Instrumentation 

 Depths (m) 



584- DC M #1 

 588- ALEX 



780- ALEX- 12 



990-ALEX-13 

 993- DC M #2 



4020-ALEX-14 



603-DCM #3 

 799-ALEX-21 

 801-DCM #4 

 lOOl-ALEX-22 



1500-ALEX-23 

 3995-850 



587-VACM 



789 T/P 



990-VACM 



1494-850 

 3995-VACM 



ALEX - Alexaev current meter (U.S.S.R.) 



DCM -digital current meter (U.S.S.R. Inst, of Oceanology, Moscow) 



VArCM-vector averaging current meter (W.H.O.I.) 



850 -Geodyne Model-850 current meter (W.H.O.I.) 



T/P -temperature/pressure recorder (IVI.I.T.) 



The proposed site will be about 500 km in diameter and 

 centered at about 29°N, 70°W. Table 9 shows the schedule 

 for the experiment. 



The Local Dynamics Experiment will consist of: 



1. U.S.S.R. synoptic-scale mooring array. The array in- 

 cludes 19 moorings with 5 current-temperature meters 

 per mooring (100, 300, 700, 1,500, 3,000, or 4,000 m) 

 for July 1977 to July 1978. The sampling time interval 

 is 30 minutes. The moorings will be located in a region 

 of 300 km diameter and will be nearly equidistant in 

 space. 



2. U.S. mooring array. A closely spaced U.S. array of 

 about eight moorings with 30 to 40 current meters and 

 temperature-pressure recorders will be moored for about 

 1 year in May 1978. Distribution of instruments on the 

 moorings will vary. One mooring will be densely instru- 

 mented from 250 m to the bottom, and all others will 

 include instruments at 500, 600, and 700 m to estimate the 

 terms of the quasi-geostrophic potential vorticity equa- 

 tion at a single point for a time period adequate to ap- 

 proach statistical stability. 



3. U.S. SOFAR floats. A complementary U.S. mapping 

 array of 60 free-floating neutrally buoyant SOFAR floats 

 at two levels, 750 and 2,000 m, will be deployed. At 

 least half of the floats will be deployed in February 1978 

 and the remainder in April 1978 in the moored array 

 region (see 1 and 2 above) at a space interval of about 

 20 km. The floats function as Lagrangian velocity devices 

 through land-based tracking stations, thereby limiting the 



geographical region in which they may be used. They 

 also telemeter average temperature. Past experience sug- 

 gests that once deployed they may be tracked for up to 

 3 years. 



4. Density surveys. CTD and XBT surveys will be 

 made from Soviet and American ships as follows: 



a) XBT and CTD surveys of an area about 500 km in 

 diameter will be made once every 40 days during the 

 year from July 1977 through July 1978; sampling 

 space interval is 30 km. The region circumscribes the 

 arrays of 1, 2, and 3 above. 



b) CTD-XBT surveys at about 25 km spacing over 

 a region about 200 km diameter are to be completed 

 in 6 days and repeated five times consecutively. The 

 profiles will extend from surface to bottom and include 

 continuous oxygen determinations and some water 

 sampling for silicate, nitrate, and phosphate analysis as 

 required. This work will be performed from May to 

 June 1978 in a region within the larger array. (See 1, 

 2, 3 above.) 



Part a will be performed by Soviet ships from July through 

 Nov. 1977 and from March through June 1978; American 

 and Soviet ships will make the surveys from Dec. 1977 through 

 Feb. 1978. Part b will be performed by U.S. ships. 



5. Additional U.S. elements for the intensive balance- 

 of-terms experiment. This is a high-accuracy, closely 

 sampled (10 km) synoptic (6 days), repeated (5 realiza- 

 tions), four-dimensional, U.S. hydrographic (CTD) sur- 



18 



