Water On Earth

Learning Goal: Explain the water cycle using appropriate terminology and explain why we are still concerned with the quantity of water on earth

Why should we study water?

1. Without water, life would not exist on Earth

2. Water is a major issue in the West

• Maybe you have heard the word drought before3. A very small percentage of water

is available for human use, and it is being polluted everyday

Define the following using the next slide

• Condensation:• Precipitation:• Evaporation:• Transpiration:• Surface run off:• Percolation:• Return flow:• Ground water flow:

Infiltration into the soil

CondensationCondensation

From vegetation

Through the soil and rock to the water table

Will we run out of water?

• If the water cycle is correct, why do we have water issues?

• There is plenty of water, but not all of it is available to use.

• So, where is all the water?

WHERE ON THE EARTH IS ALL OUR WATER ? ?

• WHAT ARE THE CHOICES?1. OCEANS2. ATMOSPHERE3. UNDERGROUND4. RIVERS, LAKES, CREEKS (OR CRICKS),

SWAMPS, PONDS ; SURFACE WATER5. ICE FIELDS AND SNOWFIELDS AND

GLACIERS• Of these choices, where is the

water found as a percent?• Which are useful to humans?

A DEMONSTRATION OF THE DISTRIBUTION OF WATER ON OUR PLANET

All the water on the earth

Salt 97% = (970 mL / 1000mL) * 100%

Fresh 3.0% = ( 30 mL / 1000 mL ) * 100%

• DISTRIBUTION OF FRESHWATER:

a) Polar ice caps 24.0 ml 2.4%

b) Groundwater 4.0 mL 0.4%

c) Surface water 1.0 mL 0.1%

d) Water vapor 1.0 mL 0.1%

Water source

Source: Nace, U.S. Geological Survey, 1967 and The Hydrologic Cycle (Pamphlet), U.S. Geological Survey, 1984

Oceans 317,000,000

Icecaps, Glaciers 7,000,000

Groundwater 2,000,000

Freshwater lakes 30,000

Inland seas 25,000

Soil moisture 16,000

Atmosphere 3,100

Rivers 300

Total 326,000,000

Water volume, incubic miles % of total water

How Much is Available?

So Why Is it important to Study Water?

• You will be testing the water quality of some wells in a town called Fruitvale.

• The first step is to collect background information on the town’s water supply

• Second, you and your team will decide which wells you are going to test based on the information you collected, and the knowledge that the water flows from north to south in that town.

• Your goals:– Determine the source of the contamination– Determine how far it has traveled