corresponding to every meridional part along the rhumb line to 

 the end of the MSQLOC area. An example of this rotation is 

 given in figure 16. When a profile for a MSQLOC has been 

 generated, BATHY calls the PUNOUT subroutine to put the MSQLOC 

 profile data on a temporary magnetic tape. MERFIX and AMP are 

 used by PUNOUT to calculate the rhumb line distance in meridional 

 parts and set up a scaling factor. The parameters are used by 

 PUNOUT to adjust the profile generated by BATHY, which is in 

 meridional parts versus depth, to a profile which shows nautical 

 miles versus depth by linear interpolation. Only when these 

 operations are complete is the MSQLOC profile data written on 

 the temporary magnetic tape and the next MSQLOC area or the next 

 profile processed. 



Each segment of a profile represents a single MSQLOC area. 

 When the individual segments are written on the temporary magnetic 

 tape the depth is in the same units as in the gridded data base 

 and the range is in nautical miles from starting point within 

 the MSQLOC area, which in each case is zero. At the end of the 

 SYNBAPSl program the temporary magnetic tape is rewound. The 

 program SYNPLOT then reads this tape either on the same or a 

 subsequent run. As each MSQLOC profile segment is read into 

 SYNPLOT it is linked in sequence to the other MSQLOC areas to 

 produce a great-circle profile. If geometric conversion to other 

 depth units is required, it is performed at this point. 



When the great-circle profile is complete, it is punched 

 out on cards and the profile is plotted. This process is 

 repeated for as many profiles as desired. Although the format 

 for the punched profile cards is fixed at eight depth-versus- 

 range points per card, the profile-plotting format is very 

 flexible. This flexibility is attained through a control card 

 for SYNPLOT, the format for which is given in figure 17. Generally, 

 whenever SYNBAPSl cannot find a MSQLOC block of gridded data on 

 the random-access storage device or the plotting dimensions are 

 not set for minimal limits (fig. 17) , the processing will halt 

 at that point and skip to the next profile, allowing the job run 

 to continue while an error message is printed out. 



The profiles generated by SYNBAPS are intended as input to 

 long-range, acoustic propagation models. Although not necessarily 

 accurate to geophysical or geodetic standards, the sythetic 

 profiles are interpolated to the accuracy required by the models. 

 A depth value is interpolated at each nautical-mile point from 

 the starting point to the terminus of the profile along a 

 great-circle path. Latitude and longitude values are rounded 

 to the nearest minute, and the range is rounded to the nearest 

 nautical mile. 



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