Water is essential for life and covers 71% of the Earth's surface. It is a chemical compound of two hydrogen atoms and one oxygen atom. The water cycle is the continuous movement of water on, above, and below the Earth's surface, including processes such as evaporation, precipitation, and runoff. Water evaporates from oceans and land into the air, condenses to form precipitation which falls back to Earth, and runs off into rivers and oceans in a continuous cycle powered by energy from the sun.

2. Introduction Water Definition
Water Cycle
Definition
Water processes
• Evaporation
• Precipitation
• Runoff

3. • Water covers 71% of the Earth's surface, is
vital for all known forms of life.
• Safe drinking water is essential to humans and
other lifeforms

4. • Water is a chemical
compound with
the chemical
formula H2O. A water
molecule contains
one oxygen and
two hydrogen atoms.

5. • The water cycle (known scientifically as
the hydrologic cycle) refers to the continuous
exchange of water within
the hydrosphere, between the
atmosphere, soil water, surface
water, groundwater, and plants.
• Water on Earth moves continually through the
watercycle of evaporation and transpiration,
condensation, precipitation, and runoff, usually
reaching the sea.

6. Evaporation
PrecipitationRunoff

7. • Evaporation from oceans and other water bodies
into the air and transpiration from land plants and
animals into air.
• Most water vapor over the oceans returns to the
oceans, but winds carry water vapor over land at
the same rate as runoff into the sea

8. • Precipitation, from water vapor condensing from the air
and falling to earth or ocean.
• Precipitation, has several forms: most
commonly rain, snow, and hail, with some contribution
from fog and dew. Dew is small drops of water that are
condensed when a high density of water vapor meets a
cool surface.

9. • Runoff from the land
usually reaching the sea.
• Water runoff often collects
over watersheds flowing
into rivers.
• Through erosion, runoff
shapes the environment
creating
river valleys and deltas whic
h provide rich soil and level
ground for the
establishment of population
centers