The Water Cycle 01/20/ a pgs  IN: Where does our water come from and where does it go?

Terms to Learn and Objectives  Be able to explain the following terms: *condensation*precipitation*runoff *evaporation*infiltration*percolation  Describe each change in the state of matter that occurs with each stage of the water cycle.  Identify the source of energy that drives the water cycle.  Illustrate the complete water cycle.

What is the water cycle?  Water Cycle – the continuous movement of water from water sources: 1. into the air 2. onto land 3. into and over the ground 4. back to the water sources

Why is the water cycle important?  The water cycle links all of the Earth’s solid, liquid, and gaseous water together.

How does water get into the air?  Evaporation – when liquid water from the Earth’s surface and from living organisms changes into water vapor.

How does water get into the air?  Transpiration: the process by which plants release water vapor into the air through their leaves.

What happens to water when it is in the air?  Condensation – when water vapor cools and changes into liquid water droplets that form clouds in the atmosphere.

How does water get back onto the ground?  Precipitation – rain, snow, sleet, or hail that falls from clouds onto the Earth’s surface.

What happens to water when it reaches the ground?  Runoff – water flows across land and collects in rivers, streams, and eventually the ocean.

What happens to water when it reaches the ground?  Infiltration – the movement of water into the ground due to the pull of gravity.

What happens to water when it reaches the ground?  Percolation – the downward movement of water through pores and other spaces in soil due to gravity.

Aquifers form when the rock layer above is porous and the layer below is impermeable.

Aquifers of Nevada

All the energy needed to drive the water cycle comes from the Sun.

 OUT: What causes water to go from one phase to another?