Notes – Chapter 18 Water Cycle and Precipitation

The Water Cycle and Processes

Hydrosphere- the Earth’s water environment. This includes rivers, lakes, ponds, oceans, and streams.

The Water Cycle Involves:

1) Evaporation – liquid water changes to a gas (water vapor). This is a “cooling” process.

2)  Condensation – water vapor changes to a liquid. This is a “warming” process.

3)  Precipitation – water falls to the ground as snow, sleet, freezing rain, rain or hail.

Types of Precipitation: The type of precipitation depends on the air temperature

a.  _Rain__ - the most common form of precipitation, consists of droplets of liquid water. Most times rain develops through the grouping of water droplets around ice crystals.

b.  _Hail___ - is by far, the least common form of precipitation. It occurs most often during the _summer_. __Cumulonimbus___ clouds produce hailstones, which can vary in size from five millimeters to larger than the size of a baseball.

c.  _Freezing rain____is defined as rain that falls as a liquid but freezes into glaze upon hitting the ground. This is called “super-cooled” water droplets that freeze on impact of __surface___.

d.  __Sleet____is defined as frozen raindrops that bounce on impact with the ground.

e.  When water vapor is frozen without passing through a stage as liquid water, it forms tiny ice crystals called ___snow_____.

4)  Transpiration – some of the water from plants evaporates into the atmosphere.

5)  Accumulation – process in which water pools in large bodies (like oceans, seas and lakes)

6)  Surface Runoff – rain, snow melt, or other water that flows over the surface of the Earth

7)  Sublimation – the process in which a solid is changed directly to a gas.

·  The water cycle is powered by energy from the sun.

· 
Heat stored in the oceans provides the energy that drives our weather and climate

On the line below the graph, write the name of the type of precipitation that is shown on the graph.

1.  __Rain______3. ___Snow______

2.  ___Freezing Rain______4. ______Sleet______