A watershed is sometimes called a what?

A watershed is an entire river system—an area drained by a river and its tributaries. It is sometimes called a drainage basin. Watersheds can cover wide areas. Runoff water from a large watershed in the midcontinental United States drains into the Gulf of Mexico through the Mississippi River system.

Explanation:

places of higher salinity. there are parts of the ocean where hardly any rain falls but warm dry winds cause lots of evaporation. this evaporation removes water – when water vapour rises into the atmosphere, it leaves the salt behind, so the salinity of the seawater increases. this causes the seawater to become denser.