Final answer:
Water can evaporate below its boiling point due to the low kinetic energy of water molecules. The high heat capacity of water and the surrounding air prevent the ocean water from boiling and evaporating on a hot day.
Step-by-step explanation:
Water can evaporate at temperatures below the boiling point. More energy is required than at the boiling point, because the kinetic energy of water molecules at temperatures below 100°C is less than that at 100°C, hence less energy is available from random thermal motions.
Water's high heat capacity allows it to absorb large quantities of heat, which is why coastal climates are more moderate than inland climates. Additionally, water's high heat of vaporization means that it requires more heat to boil than most other liquids.
Even on a very hot day, the water in the ocean doesn't boil and evaporate because the surrounding air provides energy for evaporation, but not enough to raise the temperature of the water to its boiling point.