The water cycle is renewed primarily by what source of energy?

The water cycle is renewed primarily by what source of energy?

• A. Gravity.
• B. Earth's rotation.
• C. The Sun's heat.
• D. Moon tides.

Answer: (C)

The Sun’s heat powers the water cycle. It provides the energy needed for evaporation, turning liquid water from oceans, rivers, and soils into water vapor. This energy input starts and sustains the cycle, as the vapor rises, cools, and condenses into clouds, eventually leading to precipitation that returns water to the surface. Gravity influences how water moves and how it falls, and the Earth’s rotation affects wind and circulation patterns, but neither supplies the energy that drives evaporation. Moon tides involve gravitational forces and have only a small, localized effect compared with the vast energy from the Sun. So the Sun’s heat is the primary energy source renewing the water cycle.

The Sun’s heat powers the water cycle. It provides the energy needed for evaporation, turning liquid water from oceans, rivers, and soils into water vapor. This energy input starts and sustains the cycle, as the vapor rises, cools, and condenses into clouds, eventually leading to precipitation that returns water to the surface. Gravity influences how water moves and how it falls, and the Earth’s rotation affects wind and circulation patterns, but neither supplies the energy that drives evaporation. Moon tides involve gravitational forces and have only a small, localized effect compared with the vast energy from the Sun. So the Sun’s heat is the primary energy source renewing the water cycle.