Why do hurricanes form only over warm oceans?

Hurricanes are massive storms with 200 times more energy than every electrical generation station on the planet. The source of that energy is the sun, and to get that energy into the atmosphere you need water.

Energy from the sun changes liquid water into water vapor. This process stores energy in the water molecules (latent heat). When the water vapor rises in the sky and cools it condenses back into liquid water and releases that energy. So in order to get the massive amounts of heat energy into the atmosphere to generate a hurricane you need warm water (over 26 degrees C).

Hurricanes form over warm oceans because they require warm, moist air as fuel. Warm ocean waters evaporate, creating the warm, moist air that rises and condenses, forming clouds and releasing latent heat, which further fuels the storm's growth and intensification.