Oceans are the source of marine water and rivers and other sources have fresh water.
The ocean water has the ability to adjust its salinity by many ways. he evaporation of water from the ocean and formation of iceberg increases the salinity of water.
Besides this, the inflow of fresh water in the ocean decreases the salinity of water and makes the water less salty. Other processes that decrease the salinity is precipitation both water and snow.
Melting of iceberg also decreases the salinity of water.
