The time variability of the cavitation thresholds of sea water

The investigation of the time variability of the cavitation thresholds of sea water in the three region of the World Ocean is presented. The first region is closed shallow sea gulf, the second region is in open part of Atlantic ocean, the third region is near the coast in region of powerful flow of river water. The made studies show that the time variability of the cavitation thresholds of sea water in the different region of the World Ocean is complex character and apparently connected with the presence of total daily rhythm of physical ,chemical and biological processes in the ocean, particularly, with the tidal phenomena, as well as with the fluctuations discontinuity layer under the action of internal waves.