Transcript Water Resources

Water Resources
This picture shows the size
of a sphere that would
contain all of Earth's
freshwater in comparison to
the size of the Earth. The
blue sphere sitting on the
United States, reaching
from about Salt Lake City,
Utah to Topeka, Kansas,
has a diameter of about 860
miles, with a volume of
about 332,500,000 cubic
miles. The sphere includes
all the water in the ice caps,
lakes and rivers as well as
groundwater, atmospheric
water, and even the water
in you, your dog, and your
tomato plant.
The Hydrosphere
Includes
all of the water on or near the
Earth’s surface (oceans, lakes, rivers, polar
icecaps, groundwater, & clouds)
 The
water cycle is the continuous movement of
water into the air, onto the land, and then back
to water sources.
The Water Cycle

Water is renewable because it is
circulated in the water cycle

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
Evaporation – the change of state from a liquid
to a gas (liquid water to water vapor)
Condensation – the change of state from a gas
to a liquid (water vapor to liquid water)
Precipitation – any form of water that falls to
Earth’s surface from clouds (rain, snow, etc.)
Runoff – excess water that flows off of the
surface
Global Water Distribution
Global Water Distribution
1.In what form is most of Earth’s water?
Saltwater (97%)
2.Where is most of the freshwater found?
Icecaps and glaciers (77%)
Earth’s Oceans
 All
of Earth’s oceans (Atlantic, Pacific, Indian,&
Arctic Oceans) are connected.

Oceans cover over 70% of Earth’s surface.
Surface Ocean Currents
Common
surface ocean
currents show
the flow of the
sea
In 1993, thousands of rubber
duckies washed up on Alaskan
beaches. Oceanographers
determined that a ship carrying
the toys lost a container during
a storm near Hawaii in 1992.
The ducks were used to map
ocean currents.
The Ocean
A Global Temperature Regulator
 The
main function of the world ocean is
to:
Absorb & store energy from the sun
How?
 Water absorbs and releases heat slower than
land does.


**Without the ocean, the temperature of Earth’s
atmosphere would be too extreme for life
Surface Water
Surface water is fresh water on Earth’s land
surface.
 Throughout history, people have built cities, towns,
and farms near reliable sources of surface water
b/c it provides drinking water, water for agriculture,
food (fish, shellfish), power for industry, & a means
for transportation.

Think About It ~ Can you
think of a city that is built
near a surface water
source?
River Systems
Rain & melting snow on
mountains, hills, etc.
Flows downhill forming
tributaries (streams)
Streams combine and
form rivers
Rivers drain into
oceans
Watersheds
A
watershed is the area of land that is drained
by a river.
 Pollution in the watershed can pollute the river.
Our Local Watershed
Groundwater
 Rain
and melted snow
sinks into the ground
forming groundwater.
 Less than 1% of all
Earth’s water is
groundwater

Groundwater gives
people drinking water
and supplies water for
many agricultural &
industrial needs
Groundwater

Most water that is available
for human use is found
underground.
 Water percolates through the
soil & down into the rocks
beneath.
 The water table is where the
rocks and soil are saturated
with water

In deserts, the water table may
be hundreds of meters beneath
the surface, but may be flowing
on the surface in wet regions.
Groundwater Continued…
 Aquifers
are underground formations that
contain groundwater.
 A recharge zone is an area of the surface
from which water percolates down into an
aquifer. Pollutants in a recharge zone may
enter an aquifer.
Rocks with Holes?
 Porosity
is the percentage of the total volume
of a rock that has pores (holes).

Water in aquifers is stored in the pore spaces and
flows from one pore space to another.
 Permeability
is the ability of rock or soil to
allow water to flow – water can seep through
Think – Pair - Share
1.
2.
Which of the following parts of soil is most
permeable?
Which of the following parts of soil is least
permeable?
A.
B.
C.
Sand
Gravel
Clay
Groundwater Interlude…
Groundwater Video…
Global Water Use
1.
What is the most popular use of water worldwide?
2.
Which part of the world uses the most water for
industry?
3.
Which part of the world uses the most water for
residences?
Residential Water Use
A person in the USA
uses about 300 L
(80 gal) of water
everyday. People of
developing countries
use much less per
day (~ 40L).
~ Why do you think this
is the case?
Residential Water Use
Treatment – to make it potable (safe
to drink), removes poisonous elements and
pathogens (organisms that cause illness).
 Water
Water Conservation
Residential
 How




can we use less water?
Take shorter showers, turn off water when
brushing teeth, shaving, washing dishes, etc.
Install low-flow technologies in toilets, shower
heads, and faucets.
Only run full dishwashers and washing machines.
Water the lawn less.
Industrial Water Use
 Industry
accounts for 19% of water used in
the world.
 Water is used to manufacture goods,
dispose of waste, and generate power.


It takes 1000L of water to produce 1kg of
aluminum (500,000L to manufacture a car).
Power-plant cooling systems usually pump water
from a surface water source, carry the water
through pipes in a cooling tower, then pump it
back to the water source. It returns to the source
warmer than it was before.
Water Conservation
Industry
 Develop
water
conservation plans



Recycle of cooling water
Recycle wastewater
Monetary rewards to
businesses that
conserves water
Agricultural Water Use
*It takes nearly 300L of water to produce one
ear of corn!
Plants require lots of water to grow… when an
area doesn’t get adequate rainfall, they use
irrigation methods to water the crops.
Water Conservation
Agricultural
 Drip
irrigation
systems deliver
small amounts of
water directly to
plant roots by
using perforated
tubing, reducing
evaporation and
runoff.
How Much Water Is Used?
1 slice of bread = 10 gallons
1 orange = 13 gallons
1 lb. of chicken meat = 500 gallons
1 sheet of paper = 3 gallons
1 cup of coffee = 35 gallons
1 lb. of potatoes = 100 gallons
1 lb. of corn = 110 gallons
1 cotton shirt = 700 gallons
1 egg = 400 gallons
1 lb. steel = 30 gallons
Hamburger (1/3 lbs.) = 4000 –
18000 gallons
1 lb. wheat = 110-250 gallons
How Do I Get Water if I Don’t Live Near
Water?
Water Diversion Project – rivers
can be diverted into canals that
direct and carry water great
distances.
Dams & Reservoirs – dams hold
water from a river back &
reservoirs are the lakes that form
behind the dam.
- Reservoirs can be used for drinking water,
1)
2)
-
3)
irrigation, recreation, industry
Dams can generate electricity - BIG
PROBLEMS if a dam fails!
Desalination – removes salt
from salt water. Is very
expensive and is not available for
areas far from oceans.
Water Use Summed Up
Residential Use
Water is
used for:
Water can
be
conserved
by:
Industrial Use
Agricultural Use