Question

what is the primary cause of ocean thermal expansion? increased salinity in ocean water around the north and south poles warming of ocean water due to higher global temperatures decreased evaporation rates in the tropics and surrounding environments

Explanation:

Ocean thermal expansion occurs when water warms up. As global temperatures rise, ocean water absorbs heat. According to the principle of thermal expansion (a basic physical property), when a substance (here, water) is heated, its molecules gain kinetic energy and move more vigorously, causing the substance to expand. Increased salinity around poles or decreased evaporation in tropics are not the primary causes of ocean - wide thermal expansion. The key factor is the warming of ocean water due to higher global temperatures.

Answer:

warming of ocean water due to higher global temperatures