Question

At area 1, a stream empties into the ocean. At area 2, precipitation enters the ocean in the form of rainfall. At area 3, evaporation takes place at the ocean’s surface. In which areas does the salinity of the ocean decrease?

Answer 1

1, because fresh water does not have a high sodium level, thus decreasing the salt levels of ocean.

Answer 2

Evaporation of ocean water and formation of sea ice both increase the salinity of the ocean. However these "salinity raising" factors are continually counterbalanced by processes that decrease salinity such as the continuous input of fresh water from rivers, precipitation of rain and snow, and melting of ice.