Question

Explanation for distribution of salinity of the tropics

Answer 1

The freshwater added at the surface dilutes the seawater, reduces the salinity and so makes the seawater less dense. Seawater can also be less saline near land, where rivers add freshwater. The ocean around Antarctica has a low salinity of just below 34ppt, and around the Arctic it is down to 30ppt in places.

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