1. Evaporation: As water evaporates from the ocean surface, the salts are left behind, increasing the salinity of the remaining water. This is particularly significant in warm, arid regions where evaporation rates are high.
2. Freshwater Input: The influx of freshwater from rivers, rain, and melting glaciers dilutes the seawater, reducing salinity. This effect is more prominent in regions with high precipitation and large river systems.
These two factors work in opposition to each other, creating a dynamic balance that determines the salinity of different parts of the ocean.
