Water On Earth• EXPLAIN WHY WATER IS IMPORTANT TO LIFE ON EARTH.

• DESCRIBE HOW EARTH’S WATER IS DISTRIBUTED.

• EXPLAIN HOW EARTH’S WATER MOVES THROUGH THE WATER CYCLE

How Much Water Do You Use?

Where Is Water Found?

Water vapor 0.04%

Water vapor 0.04%

Ice 69%Ice 69%

Groundwater 30%

Groundwater 30%

Lakes and rivers 0.26%

Lakes and rivers 0.26%

Why Is Water Important?

• All living things need water to carry out their body processes

• Both Consist mostly of water

• Without water, neither us nor the apple (we) could survive

• Water allows organisms to break down food, grow, reproduce, and obtain and use materials they need from their environments

Where Are Earth’s Water Sources?

H is for Huron.O is for Ontario.M is for Michigan.E is for Erie.S is for Superior

5 Great Lakes – 20%

What Is the Water Cycle?

EvaporationTranspiration

Condensation

Runoff

Precipitation

Evaporation – the process by which molecules at the surface of a liquid change to a gaseous state

Transpiration – evaporation of water from plant leaves.

Condensation – is the change of water from its gaseous form (water vapor) into liquid water.

Precipitation – When water falls from the earth in the form of rain, snow, hail, or sleet.

Runoff – the remaining water runs off the surface into streams, lakes, or into the groundwater.

Groundwater• Water that fills the cracks and spaces in

underground soil and rock layer

Overview

2. What water cycle process can you observe in the photo?

1. What are the three major steps in the water cycle?

3. What percentage of water on Earth is fresh water?

Condensation

Evaporation, condensation, and precipitation

3 percent

Surface Water• TELL WHAT A RIVER SYSTEM IS.

• EXPLAIN HOW PONDS AND LAKES FORM.

• DESCRIBE THE CHANGES THAT OCCUR IN PONDS AND LAKES.

• As you follow one small stream, you’ll notice that it eventually joins another stream forming a larger stream. Eventually it joins other streams until a small river forms.

What Is a River System?

• Tributaries - The streams and small rivers that feed into a main river

What Is a Watershed?

Platte River• All the water in a river

system drains into a main river.

• Watershed - The land area that supplies water to a

river system

What Is a Divide?

Watershed

Divide

Divide – One watershed is separated from another by a ridge of land

• Streams on each side of the divide flow in different directions.

What Are Ponds and Lakes?

Contain water

•Smaller •Shallower• Sunlight reaches the bottom• Algae

• Deeper• Darker/Little Sunlight•Few Plants• Colder• Large fish

Ponds Lakes

• Unlike streams or rivers, ponds and lakes contain still water

• Ponds and lakes form when water collects in hollows and low-lying areas of land

How Do Lakes Form?

Volcanic lake Rift valley lake

Glacial lakes

• Lakes can form through several natural processes

• Ice sheets that melted

How Can Lakes Change?

Organisms release wastes and nutrients into the water.

Dead organisms pile up on the bottom of the lake, making it shallower.

Over time, the lake becomes filled in, forming a meadow.

3

1

2

Model the Water Cycle

Water collects in lakes and oceans.

Runoff to a river system and groundwater

Precipitation CondensationEvaporation

Transpiration