GEOLOGY

Detailed explanation-1: -The saltiest locations in the ocean are the regions where evaporation is highest or in large bodies of water where there is no outlet into the ocean. The saltiest ocean water is in the Red Sea and in the Persian Gulf region (around 40‰) due to very high evaporation and little fresh water inflow.

Detailed explanation-2: -Evaporation increases the salinity of seawater because when seawater evaporates, the salts are left behind, thus increasing their concentration. Precipitation and river input decrease salinity because the input of freshwater dilutes the salts in seawater, thus decreasing their concentration.

Detailed explanation-3: -Equator has higher levels of salinity than tropics due to higher levels of evaporation.

Detailed explanation-4: -In subtropical latitudes, high sur-face evaporation creates high salinity near the sea surface. In subpolar latitudes, high precipitation creates low salinity near the sea surface.

Detailed explanation-5: -The least saline ocean, by comparison, is the Arctic Ocean, which has a typical salinity of 28–30 g/kg owing to the low rate of evaporation and meltwater from the ice-caps.