Water Cycle

Water Cycle (Hydrologic Cycle)

The continuous process by which water moves from Earth\'s surface to the atmosphere and back again, driven by solar energy and gravity.

Evaporation

The process where liquid water is heated by the Sun and changes into a gas called water vapor, rising into the atmosphere.

Condensation

The process where water vapor cools down and changes back into liquid water droplets, which cluster together to form clouds.

Precipitation

Any form of water that falls from the atmosphere to Earth\'s surface, including rain, snow, sleet, and hail.

Transpiration

The process by which plants release water vapor into the air through small pores in their leaves called stomata.

Sublimation

The rare process where water changes directly from a solid (ice or snow) into a gas (water vapor) without melting into a liquid first.

Infiltration

The process by which water on the ground surface enters and soaks into the soil and rocks.

Runoff

Water that flows over the land surface rather than soaking into the ground, eventually collecting in streams, rivers, and oceans.

Groundwater

Water that is stored beneath the Earth\'s surface in the spaces between rocks and soil particles.

Aquifer

An underground layer of water-bearing permeable rock, gravel, or sand from which groundwater can be extracted using a well.

Collection

The stage of the water cycle where water pools in large bodies such as oceans, lakes, and reservoirs.

The Sun

The primary energy source that powers the water cycle by providing the heat necessary for evaporation.

Gravity

The force that pulls precipitation down to Earth and causes runoff to flow downhill toward the oceans.

Percolation

The downward movement of water through the soil and various rock layers toward the water table.

Advection

The horizontal movement of water, such as clouds or water vapor, through the atmosphere due to wind.

Percentage of Earth\'s Water in Oceans

Approximately 97\% of Earth\'s water is salt water found in the oceans.

Percentage of Earth\'s Freshwater

Only about 3\% of the water on Earth is freshwater, and most of that is frozen in glaciers and ice caps.