The water cycle describes the continuous movement of water on, above, and below the Earth's surface. Water exists as a liquid, vapor, and solid states as it moves through the water cycle, which includes processes like evaporation, condensation, precipitation, and runoff. The sun drives evaporation of water from sources like oceans, lakes, and soil into water vapor in the atmosphere, which then condenses to form precipitation like rain, snow, hail, or fog that falls back to the Earth's surface, completing the cycle.

1. Water Cycle
What is Water ?
• Water is a liquid at standard ambient temperature and pressure.
• Water covers 71% of the Earth's surface, and is vital for all known forms of life.
What is Cycle?
• It means continous. Like a circle with no end.
What is Water Cycle?
• The water cycle,
also known as
the hydrologic cycle or
the H2O cycle, describes
the continuous
movement of water on,
above and below the
surface of the Earth.
Although the balance of
water on Earth remains
fairly constant over time,
individual water
molecules can come and
go, in and out of the
atmosphere.
Precipitation
• Condensed water vapor that falls to the Earth's surface . Most precipitation occurs as rain, but
also includes snow, hail, fog drip.
• RAIN - is liquid water in the form of droplets that have condensed from atmospheric water
vapor and then precipitated
• SNOW - form of flakes of crystalline water ice that fall from clouds.
• HAIL -It consists of balls or irregular lumps of ice, each of which is called a hailstone.
• FOG DRIP - forms when fog droplets condense on the needles or leaves of trees or other objects,
and drip to the ground.
Evaporation
• is a type of vaporization of a liquid that occurs from the surface of a liquid into a gaseous phase
that is not saturated with the evaporating substance.
• Evaporation is an essential part of the water cycle. The sun (solar energy) drives evaporation of
water from oceans, lakes, moisture in the soil, and other sources of water.

2. Condensation
• Condensation is the change of the physical state of matter from gaseous phase into liquid
phase, and is the reverse of vaporization.
OTHER parts of the Water Cycle
Runoff
• The variety of ways by which water moves across the land. This includes both surface runoff and
channel runoff. As it flows, the water may seep into the ground, evaporate into the air, become
stored in lakes or reservoirs, or be extracted for agricultural or other human uses.
Transpiration
Transpiration is the process of water movement through a plant and
its evaporation from aerial parts especially from leaves but also
from stems and flowers. Leaf surfaces are dotted with pores which
are called stomata, and in most plants they are more numerous on
the undersides of the foliage.
Infiltration
• The flow of water from the ground surface
into the ground. Once infiltrated, the water
becomes soil moisture or groundwater.

3. Percolation
Percolation is a hydrologic process where water moves
downward from surface water to groundwater. This process
usually occurs in the vadosezone below plant roots and is
often expressed as a flux to the water table surface.