Question

though caspian sea is enclosed ,its salinity is just 14 to 17 parts per thousand.why it is so

Answer 1

Because the evaporation is less than its rainfall.

Answer 2

The capsian sea is enclosed from all sides.

But unlike many other seas, Capsian sea is very less saline.

Infact it is only, 14 to 17 percent saline.

This happens because there is a regular and constant flow of freshwater.

This makes the salt more soluble and thus reducing the salinity.