Transcript 13.1 Notes

MILLER/SPOOLMAN
LIVING IN THE ENVIRONMENT
Chapter 13
Water Resources
17TH
Case Study: The Colorado River Basin— An
Overtapped Resource (1)
7
• Flows 2,300 km through ______
U.S. states to the
Gulf of California
• 14 major dams and
reservoirs
desert
• Located in a __________
area
• Water supplied mostly
snowmelt
from ______________
of
the Rocky Mountains
Case Study: The Colorado River Basin— An
Overtapped Resource (2)
• Supplies water and electricity for about
30 million
__________________
people
• Las Vegas, Los Angeles, San Diego
15% of the nation’s crops
• Used to produce about ______
and livestock
• Very little water reaches the Gulf of California
too much
because we use _____________
of it
• Prolonged dry weather since __________
1999
Aerial View of Glen Canyon Dam Across the Colorado
River and Lake Powell
2nd largest
Lake Powell - _____________________
reservoir in the U.S
Fig. 13-2, p. 317
13-1 Will We Have Enough Usable
Water?
• Concept 13-1A We are using available freshwater
unsustainably by wasting it, polluting it, and
charging too little for this irreplaceable natural
resource.
• Concept 13-1B One of every six people does not have
sufficient access to clean water, and this situation
will almost certainly get worse.
Freshwater Is an Irreplaceable Resource That
We Are Managing Poorly (1)
• Why is water so important?
•
•
•
•
Needed for our __________
cells
surface
Plays a key role in sculpting the earth’s ___________
climate
Moderates earth’s ________________
dilutes
Removes and ______________
some of the pollutants
we produce
71% of the
• Earth is a watery world….covers _______
planet’s surface
• Poorly managed resource
waste
pollute
• We ______________
and _______________
it
little
• Charge too ________________
for making it available
Freshwater Is an Irreplaceable Resource That
We Are Managing Poorly (2)
• Access to water is…
health
• A global ______________
issue - World Health Organization
WHO estimates that 3,900 children under age five
(______)
die every day from waterborne infectious diseases
economic
• An ________________
issue – vital for producing food and
energy
• A ________________
and children’s issue – females in
women’s
LDCs are often responsible for finding and carrying water
_______
global
• A national and _____________
security issue – nations
share
often ___________
water resources
Girl Carrying Well Water over Dried Out Earth during
a Severe Drought in India
Fig. 13-3, p. 319
Most of the Earth’s Freshwater Is Not
Available to Us
• Only a tiny fraction of our world’s water supply is
0.024%
available for freshwater use: ________
• Groundwater, lakes, rivers, streams
• Fortunately our freshwater is continually recycled,
hydrologic
purified, and distributed by the _______________
cycle
overload
• We can still _________________
this cycle though
haves
• Globally people are divided into “Water _________”
have-nots
and Water ___________”
Condensation
Condensation
Ice and
snow
Transpiration
from plants
Precipitatio
n to land
Evaporation of
surface water
Evaporation
from ocean
Runoff
Lakes and
reservoirs
Precipitatio
n to ocean
Runoff
Infiltration and
percolation into
aquifer
Increased runoff on land
covered with crops,
buildings and pavement
Increased runoff
from cutting
forests and filling
wetlands
Runoff
Groundwater
in aquifers
Overpumping
of aquifers
Water pollution
Runoff
Ocean
Natural process
Natural reservoir
Human impacts
Natural pathway
Pathway affected by human activities
Fig. 3-16, p. 67
Groundwater and Surface Water Are
Critical Resources (1)
• Ground Water
downward
• Water that percolates _______________
through
spaces in soil, gravel, and rock
• Zone of saturation
• Below a certain depth spaces in soil are completely
filled
____________
with water
• Water table
top
• ____________
of zone of saturation…can rise or fall
Groundwater and Surface Water Are
Critical Resources (2)
• Aquifers
caverns
• Underground _______________
and porous layers of
rock through which groundwater flows at a typical
1 m / year
speed of ___________
precipitation
• Natural recharge – through ________________
• __________________
recharge – from nearby lakes,
Lateral
rivers, or streams
slow
• Recharge in general is very ______________
Groundwater and Surface Water Are
Critical Resources (2)
Runoff
• Surface _____________
• water that does not
infiltrate the ground or
evaporate back into the
atmosphere
• Watershed
• the land from which
drains
water ___________
into
a particular river, lake, etc…
drainage basin
• Also called a ______________________
We Use Much of the World’s Reliable
Runoff
• 2/3 of surface runoff is lost by seasonal floods
reliable
• 1/3 is considered _______________
runoff = usable
freshwater
Currently = use 34%
By 2050 = 90%
• World-wide averages of water use
• Domestic: 10%
• Agriculture: 70%
• Industrial use: 20%
Science Focus: Water Footprints and
Virtual Water (1)
Footprint
• Water ________________
• Volume of water we use directly and indirectly to stay
alive and support our lifestyles
• Average American uses 260 liters per day…enough to
1.7 typical bathtubs
fill ______
• Flushing toilets, 27% Washing clothes, 22%
• Taking showers, 17% Running faucets, 16%
• Wasted from leaks, 14%
19 liters
• World’s poorest use ________________
per day
Science Focus: Water Footprints and
Virtual Water (2)
Virtual
• ________________water…
water that is used
indirectly to provide us food and other consumer
products
• Producing and delivering a typical hamburger requires
2400 liters
_________________
of water (16 bathtubs)
• Most of which is used to grow the grain that is fed to
cattle
• Virtual water products are ________________
by
imported
many countries so that they can save real water
1 tub = 151 liters (40 gallons)
= 1 tub
= 4 tubs
= 16 tubs
= 17 tubs
= 72 tubs
= 2,600 tubs
= 16,600 tubs
Fig. 13-A, p. 321
Case Study: Freshwater Resources in
the United States
• The U.S. has more than enough renewable
unevenly
freshwater, but it is _________________
distributed
agricultural
and much is contaminated due to _______________
industrial
and _________________
practices
flooding
• Our water supply is also affected by _____________
drought
and _______________....
– a prolonged period in
70% lower than
which precipitation is at least ________
average
Average annual precipitation (centimeters)
Less than 41
41-81
81-122
More than 122
Why do you think
that some areas
with moderate
precipitation still
suffer from water
shortages?
Over use
Acute shortage
Shortage
Adequate supply
Metropolitan regions with population greater than 1 million
Fig. 13-4, p. 322
Water Hotspots in 17 Western U.S. States
U.S. Department of the
Interior has identified
17 water hotspots in
our western states
At least a total of 36
states are predicted
to face water shortages
by 2013 due to…
drought
Rising temperatures
Pop. growth
Urban sprawl
Increased water use
Fig. 13-5, p. 322
Case Study: The Colorado River Basin—
Misuse of a Resource
• Why/How is the Colorado River Basin misused?
dry land
1. Extremely _____
moderate flow for its size
2. Only a __________
3. A legal __________
pact
signed by the U.S. and Mexico
in 1922 (and 1944) allocated more water for human
use than the river can supply
4. Since 1960, the river has rarely flowed all the way
Gulf of California
to the _____________________
pollutants
5. Receives enormous amounts of _______________
from urban areas, farms, and industries
Water Shortages Will Grow (1)
30
• More than ________
countries – most in the Middle
East and Africa – now face stress from water scarcity
60
• By 2050 some _______
countries – may in Asia –
may face water scarcity
• Due to the growing human population…China and
urbanization
30% earth’s land area experiences severe drought
• ______
45% by 2059 from climate change
• Will rise to _______
Natural Capital Degradation: Stress on the
World’s Major River Basins
Fig. 13-6, p. 323
Water Shortages Will Grow (2)
• In 2009, the United Nations reported that about 1.2
1 out of every 6
billion people ( ______________________)
lacked
regular access to enough clean water
3 billion
• By 2025, it is projected that ___________________
are likely to lack enough clean water
• As water shortages increase, so will….
malnutrition
• ___________________
• The need for grain _____________
imports
prices
• Food ___________
Review Questions
• What is a watershed or drainage basin?
The area where water
drains into a nearby
river, lake, etc.
Review Questions
• Why are water shortages expected to grow?
Climate change
Increased water use
Growing population
Urban sprawl
• What is virtual water?
Water that is indirectly used to make a product
• What is reliable runoff?
Surface water that is available for freshwater use