Why are oceans salty?

 

Oceans are salty because of the process of evaporation. When water evaporates, it leaves behind the salt. The more evaporation that occurs, the saltier the water becomes.

The ocean is also salty because of the rivers that flow into it. Rivers carry dissolved minerals from the land, which add to the ocean's saltiness. The ocean's saltiness also comes from rocks on the sea floor. These rocks are constantly dissolving, and the minerals they contain add to the ocean's saltiness. Finally, the ocean is salty because of the marine life that lives in it. Marine creatures excrete salt, which adds to the ocean's salinity.