FIGURES (con.) 



Page 



5-8. - Percent occurrence of layer depth in North Atlantic 



by season 53 



5-9. - The change in average midocean surface salinities in 

 response to latitudinal changes in evaporation and 

 precipitation 54 



5-10.- Temperature and salinity of the water masses of the 



Atlantic Ocean 55 



5-11.- The geographic distribution of water masses that have common 



vertical salinity and temperature distributions 56 



5-12.- Basic temperature and sound velocity structure of the 



ocean 57 



5-13.- Sound channel axis depth vs latitude (55°W longitude) 58 



5-14.- Sound transmission modes (schematic) 59 



6 - Waves in the Ocean 



6~1. - Simple sea wave and its parts 60 



6-2. - Wave profile and water particle motions 61 



6-3. - Streamlines of flow in finite amplitude capillary waves 62 



6-4. - Speed of gravity waves and capillary waves as a function 



of their wavelength 63 



6-5. - Sea state code 64 



6-6. - Deepwater ambient noise levels 65 



6-7. - Sea state and acoustic loss at the sea surface 66 



6-8. - Comparison of an observed wave spectrum to empirical 



spectra of Pierson-Moskowitz 67 



6-9. - Isotherms in internal wave motions 68 



6-10.- Internal wave spectra 69 



6-11.- Diagram of rays in the sound medium, which has an internal 



wave on the thermocline 70 



vii 



