Rock Cycle and Mineral
Resources

Lecture 10

The Earth Is a Dynamic
Planet

´ Geology
´ Study of dynamic processes taking place on the earth’s surface

and in its interior

´ Three major concentric zones of the earth
´ Core (Inner and Outer)

´ Mantle, including the asthenosphere

´ Crust
´ Continental crust

´ Oceanic crust: 71% of crust

What Are Rocks?

´ Mineral
´ Naturally occurring chemical element or compound that exists

as a crystalline solid

´ Mineral resource
´ Concentration that we can extract and process into raw

materials

´ Nonrenewable

´ Rock
´ Solid combination of one or more minerals

Igneous Rocks

´ Igneous rocks
´ Igneous—“fiery inception”

´ Magma—molten rock
beneath Earth’s surface

´ Lava—molten rock when it
flows onto Earth’s surface

Slow Cooling – bigger
minerals with distinct
crystal structure

Fast cooling – very fine
grained, not crystalline

Intrusive vs Extrusive Rocks

Examples of Intrusive Igneous Rocks

´ Diorite is a coarse-grained,
intrusive igneous rock.

Granite is a coarse-grained,
light colored, intrusive igneous
rock.

Examples of Extrusive Igneous Rocks

Basalt is a fine-grained,
dark-colored extrusive
igneous rock.

Obsidian is a dark-
colored volcanic glass
that forms from the
very rapid cooling of
molten rock material.
It cools so rapidly that
crystals do not form.

Pumice is a light-colored
vesicular igneous rock. It forms
through very rapid solidification
of a melt. The vesicular texture
is a result of gas trapped in the
melt at the time of solidification.

Oceanic and Continental Crust

´ Oceanic Crust made up of
Basalt (extrusive igneous
rock)

´ Continental Crust made up
of Granite (intrusive igneous
rock)

´ Basalt is denser than granite

Sedimentary Rocks
 Composed of cemented mineral

grains/rock fragments

´ Created by:
´ Weathering: breaking rocks into smaller

pieces

´ Erosion: removing grains from parent rock

´ Transportation: dispersed by gravity, wind,
water, and ice

´ Deposition: settling out of the transporting
fluid

´ Lithification: transforming into solid rock

Sedimentary Rocks

 Geologists define four classes of sedimentary rock.
´ Clastic: rock fragments (clasts) cemented together

´ Biochemical: cemented shells of organisms

´ Organic: carbon-rich remains of plants or other organisms

´ Chemical: minerals that crystallize from water

ChemicalClastic OrganicBiochemical

Clastic Sedimentary
Rocks

 Clast size/grain size
 Diameter of

fragments/grains
 Range from very coarse to

very fine
 Boulder, cobble, pebble,

sand, silt, and clay
´ Gravel: coarse-grained sediment

(cobble, pebble).
´ Mud: fine-grained (silt and clay)
´ As transport distance increases,

grain size decreases.

Examples of Clastic Sedimentary Rocks

Conglomerate
– clasts are
gravel sized or
larger.

Sandstone
– clasts are
sand grain
sized.

Shale
-clasts are
the size of
clay grains.

Biochemical
Sedimentary Rocks

 Biochemical limestone
´ Principle compound is CaCO3

´ Forms in warm, tropical, shallow, clear, O2-rich, marine
water

´ Composed of shell debris from diverse community
(corals, clams, oysters, snails, brachiopods, plankton,
forams, cocolithophores)

Organic
Sedimentary Rocks

 Made of organic carbon—
the soft tissues of living
things
 Coal—altered remains of

fossil vegetation
´ Accumulates in lush,

tropical wetland settings

´ Requires deposition in the
absence of oxygen

 Oil shale—shale with heat
altered organic matter
(Kerogen)

Chemical Sedimentary Rocks
 Evaporites—from evaporated seawater

´ Evaporation causes minerals to precipitate.
´ Thick deposits are the result of large volumes of water evaporating.
´ Minerals include halite and gypsum.

 Travertine—precipitated from groundwater
´ Occurs when groundwater reaches the surface
´ CO2 expelled into the air; reduced ability to hold carbonate.

´ Evaporation can also cause CaCO3 to precipitate.
´ Example: thermal (hot) or cold water springs and cave settings

´ In cave settings, Travertine builds up complex growth forms speleothems

Metamorphic Rocks

 Metamorphic rock—solid-state alteration of a
protolith
´ Meta = change

´ Morphe = form

 Rocks which were originally igneous or
sedimentary and have been changed by heat
and pressure

 Rearrange the crystal structure of the original rock

 Limestone becomes marble; sandstone becomes
quartzite, shale becomes slate

Metamorphic
Rocks
 Protoliths undergo slow solid-state changes in:

´ Mineralogy

´ Texture

 Metamorphic changes are due to variations in:
´ Temperature

´ Pressure

´ Tectonic stresses (compression and shear)

´ Amount of reactive water (hydrothermal fluid)

Types of Metamorphic Rocks

 Two major subdivisions—foliated and nonfoliated

´ Foliated—have a throughgoing planar fabric
´ Subjected to differential stress
´ Have a significant component of platy minerals

´ Classified by composition, grain size, and foliation
type

Foliation

 Foliation—Latin folium, for leaf
´ Parallel planar surfaces or

layers in metamorphic rock

´ Gives the rock a streaked or
striped appearance

´ Foliated rocks often break
along foliation planes

 Due to
´ Preferred inequant mineral

orientation, or

´ Compositional banding (dark
and light layers)

Foliated Metamorphic Rock

Types of Metamorphic Rocks

 Nonfoliated—no planar
fabric evident
´Minerals recrystallized without

compression or shear.

´Comprised of equant minerals
only

´Classified by mineral
composition

NonFoliated Metamorphic Rock

The Earth’s Rocks Are Recycled Slowly

 Rock cycle
´Rocks are recycled over millions of years
´Erosion, melting, and metamorphism
´Slowest of the earth’s cycle processes

The Earth Is a Dynamic Planet

Minerals

´ Naturally occurring
´ Solid
´ Formed geologically
´ Crystalline structure
´ Definite chemical
´ composition
´ Mostly inorganic

28 © 2011 Pearson Education, Inc.

Mineral Classes

 Oxides (O2-)
´ Metal cations (Fe2+, Fe3+,

Ti2+) bonded to oxygen.
´ Examples

´ Magnetite (Fe3O4)

´ Hematite (Fe2O3)
´ Rutile (TiO2)

 Halides (Cl- or F-)
´ Examples

´ Fluorite (CaF2)

´ Halite (NaCl)

29 © 2011 Pearson Education, Inc.

Mineral classes

 Carbonates (CO32-)

´ Examples

´ Calcite (CaCO3)

´ Dolomite (Ca, Mg[CO3]2)

 Native metals

´ Pure masses of a single metal

´ Examples

´ Copper (Cu)

´ Gold (Au)

Mineral Classes

 Sulfides (S–)

´ Metal cations bonded to a sulfide anion.

´ Examples

´ Pyrite (FeS2)

´ Galena (PbS)

 Sulfates (SO42-)

´ Metal cation bonded to a sulfate anionic group.

´ Many sulfates form by evaporation of seawater.

´ Examples

´ Gypsum (CaSO42H2O)

´ Anhydrite (CaSO4)

Mineral Classes

´ Oxygen and Silicon are the two most abundant
elements in the crust.

 Silicates – Silica- 4 oxygen atoms surround a single
silicon atom, forming (SiO4)4- Each oxygen atom
covalently shares 1 electron with the silicon atom,
jointly filling its outermost shell.

Mineral Resources

 Naturally occurring mineral deposit

´ Concentrated

´ Can be extracted and used

´ Some are a single element

´ – Cu, Au, diamonds

´ Most are compounds

´ – NaCl, CaSO4

´ Metallic or nonmetallic

´ High and low-grade ores

We Depend on a Variety of
Nonrenewable Mineral Resources

 Ore
´Contains profitable concentration of

a mineral
´May be high-grade or low-grade

 Metallic mineral resources
´Aluminum
´Steel: a mixture of iron and other

elements
´Copper
´Gold
´Molybdenum

We Depend on a Variety of
Nonrenewable Mineral Resources

´ Nonmetallic mineral resources
´Sand
´Gravel
´Limestone
´Phosphate

Life Cycle of a Mineral Resource

 Mineral resources go through life cycle
´ Mining

– Locate and extract
´ Conversion to products

– Purify useful mineral
– Manufacture product

´ Disposal or recycling
– Some minerals corrode away
– Metals wear through friction
– Some are pollutants
– Metals commonly are recycled

Supplies of Nonrenewable Mineral
Resources Can Be Economically Depleted

´ Reserves
´Identified deposits from which we can extract the

mineral profitably at current prices
´ Economic depletion

´Occurs when extraction costs more than remaining
deposits are worth

´ Depletion time
´Time to use a certain portion (usually 80%) of reserves

at a given rate of use

Supplies of Nonrenewable Mineral
Resources Can Be Economically Depleted

´ Options when a resource becomes
economically depleted
´Recycle or reuse existing supplies
´Waste less
´Use less
´Find a substitute
´Do without

What Are The Environmental Effects of Using
Nonrenewable Mineral Resources?

´ Extracting minerals from the earth’s crust and converting
them into useful products:
´ Disturbs the land

´ Erodes soils

´ Produces large amounts of solid waste

´ Pollutes the air, water, and soil

E N E R G Y E F F I C I E N C Y &
R E N E W A B L E E N E R G Y

R E S O U R C E S
L E C T U R E 1 2

W H Y D O W E N E E D A N E W
E N E R G Y T R A N S I T I O N ?

• World is in early stages of a transition
– Move from fossil fuels to energy

efficiency and renewable energy

• Cost of generating energy with solar
energy fell by 82% between 2009 and
2015

– Wind costs fell 61%

• Costa Rica gets more than 90% of its
energy from renewable resources

W H Y I S I M P R O V I N G E N E R G Y E F F I C I E N C Y A N D
R E D U C I N G E N E R G Y W A S T E A N I M P O R TA N T E N E R G Y
R E S O U R C E ?

• Improvements in energy efficiency and
reductions in energy waste

– Could save at least one-third of the
energy used in the world

• Up to 43% of energy used in the
United States

• Many technologies exist for increasing
energy efficiency of industry, vehicles,
appliances, and buildings

W E WA S T E A LO T O F
E N E R G Y A N D M O N E Y

• Energy efficiency
– How much useful work we get from

each unit energy

• Energy conservation
– Reducing or eliminating unnecessary

energy waste

W E WA S T E A LO T O F
E N E R G Y A N D M O N E Y

• Some sources of waste

– Poorly insulated buildings

– Reliance on cars for getting around

– Huge data centers filled with electronic servers

• Use only 10% of energy they consume

– Motor vehicles with internal combustion engines
(25% efficiency)

– Nuclear, coal, and natural gas power plants (1/3rd

electricity)

I M P R O V I N G E N E R G Y
E F F I C I E N C Y I N I N D U S T R I E S
A N D U T I L I T I E S

• Cogeneration
– Combined heat and power

– Two forms of energy from same fuel source

• Replace energy-wasting electric motors
(consume 60% of electricity used)

• Recycle materials (75% less high quality energy;
40% less CO2)

• Use energy-efficient LED lighting
• Smart meter to monitor energy use
• Shut down unused computers and lights

BUILDING A SMARTER AND MORE
ENERGY-EFFICIENT ELECTRICAL GRID
• Current electrical grid system–outdated and

wasteful

• Smart grid
– Ultra-high-voltage

– Super-efficient transmission lines

– Digitally controlled

– Responds to local changes in demand and supply

– Easier to buy renewable energy

M A K I N G T R A N S P O R TAT I O N
M O R E E N E R G Y – E F F I C I E N T

• Hidden costs in gasoline

– Government subsidies and tax breaks for oil
companies

– All hidden costs add up to $12 per gallon

• Build or expand mass transit and high speed rail

• Carry more freight by rail instead of trucks

• Encourage biking by building bike lanes

S W I T C H I N G T O E N E R G Y –
E F F I C I E N T V E H I C L E S

• Gasoline-electric hybrid car
• Plug-in hybrid electric vehicle
• Electric vehicle with a hydrogen fuel

cell

• Car bodies made of light, composite
materials

D E S I G N I N G B U I L D I N G S
T H AT S AV E E N E R G Y A N D
M O N E Y

• Green architecture
• Living or green roofs

– Specially formulated soil and vegetation

• Superinsulation
– No need for heating system

• U.S. Green Building Council’s Leadership
in Energy and Environmental Design
(LEED)

– Standards

WHY ARE WE WASTING SO MUCH
ENERGY AND MONEY?
• Energy remains artificially cheap

– Government subsidies

– Tax breaks

– Prices don’t include true cost

• Few large and long-lasting incentives for improving
energy efficiency and reducing waste

• Rebound effect (using more energy when they buy
energy efficient devices)

R E LY I N G M O R E O N
R E N E WA B L E E N E R G Y

• Reasons renewable energy use is not more
prevalent

– Inaccurate perceptions that solar and wind
energy are unreliable and intermittent

– Government subsidies and tax breaks lower for
renewable energy than for fossil fuels

– Prices for nonrenewable energy do not include
harmful environmental impacts

– Energy shift takes many decades

H E AT I N G B U I L D I N G S A N D
W AT E R W I T H S O L A R
E N E R G Y

• Passive solar heating system
– Absorbs and stores heat from the

sun directly within a well-insulated
structure

• Active solar heating system
– Captures energy from the sun in a

heat-absorbing fluid

C O O L I N G B U I L D I N G S
N AT U R A L LY

• Methods to keep a building cool
– Open windows when cooler outside

– Use fans

– Superinsulation and high-efficiency windows

– Shade trees, overhangs, or window awnings

– Light-colored roof

– Geothermal heat pumps bring cool air from
underground

C O N C E N T R AT I N G S U N L I G H T T O
P R O D U C E H I G H – T E M P E R AT U R E
H E AT A N D E L E C T R I C I T Y
• Solar thermal systems

– Collect sunlight to boil water and produce steam to
generate electricity

– Used in deserts and open areas with ample sunlight

– Require large volumes of cooling water for condensing
steam and cleaning mirrors

• Low net energy yields

SOL AR COOKERS

• Solar cookers can replace wood and charcoal fires

USING SOL AR CELLS TO PRODUCE
ELECTRICIT Y
• Photovoltaic (PV) cells

– Convert solar energy to electric energy

• Design of solar cells
– Sunlight hits cells and produces flow of electrons

– Systems can be connected to existing electrical
grids or to batteries

USING SOL AR CELLS TO PRODUCE
ELECTRICIT Y

• Solar cells made of paper-thin, rigid, or
flexible sheets

– Enabled by nanotechnology and other
emerging technologies

• Rural use of solar
– Rooftop solar panels power LED lamps

– Solar powered microgrids

U S I N G W I N D T O
P R O D U C E E L E C T R I C I T Y

• Tall, long-blade turbines can extract more
energy from the wind

• Rapidly growing power source
– The United States, China, and Germany

• Future is offshore wind farms
• Wind power has potential to produce 40

times the world’s current electricity used

U S I N G W I N D T O
P R O D U C E E L E C T R I C I T Y

• Wind is abundant, widely distributed, and
inexhaustible

– Mostly carbon-free and pollution-free

• High net energy yield
• Largest potential areas are usually rural

– Smart grid needed to connect

• Backup power source may be needed
– Alternative: large number of wind farms in

different areas connected to smart grid

TA P P I N G I N T O T H E
E A R T H ’ S I N T E R N A L H E AT

• Geothermal energy
– Heat stored in soil, underground rocks, and

fluids in the earth’s mantle

• Geothermal heat pump system
– Uses temperature difference between the

earth’s surface and underground

– Fluid carried through a closed loop

– Can heat a building in winter and cool it in
summer

TA P P I N G I N T O T H E
E A R T H ’ S I N T E R N A L H E AT

• Hydrothermal reservoirs
– Drill wells and extract dry steam, wet

steam, or hot water

– The United States is the world’s largest
producer

– Drilling geothermal wells is expensive

• 2015: 134 new geothermal power plants
under construction or development in
the United States

P R O D U C I N G E N E R G Y B Y
B U R N I N G S O L I D B I O M A S S

• Biomass
– Plant materials and agricultural waste

that can be burned for fuel

• Biomass plantations
– Fast growing trees and shrubs for

repeated harvest

– Wood pellet production degrades
forests

• Burning wood and other forms of
biomass produces CO2 and pollutants

USING LIQUID BIOFUELS TO POWER
VEHICLES
• Ethanol

– Ethyl alcohol produced from plants

• Biodiesel
– Produced from vegetable oils

• Advantages
– Crops can be grown throughout the world

– No net increase in CO2 emissions under
certain circumstances

– Easy to store and transport

U S I N G L I Q U I D B I O F U E L S
T O P O W E R V E H I C L E S

• Brazil makes ethanol from sugarcane residue
– Medium net energy

• 2014: 43% of the corn produced in the
United States was used to make ethanol

– Corn-based ethanol has a low net energy

– Producing and burning corn-based ethanol
adds 20% more greenhouse gases than
burning gasoline

U S I N G L I Q U I D B I O F U E L S
T O P O W E R V E H I C L E S

• Growing corn requires much water
• Ethanol distilleries produce large

volumes of wastewater

• Cellulosic ethanol
– Alternative made of inedible cellulose

– Can be made from grasses that do
not require fertilizer or replanting
(perennials)

• Algae can produce biofuel

P R O D U C I N G E L E C T R I C I T Y
F R O M FA L L I N G A N D
F L O W I N G W AT E R

• Hydropower
– Uses kinetic energy of moving water

– Indirect form of solar energy

– World’s leading renewable energy source

• Top three producers
– China, Canada, and Brazil

• Hydropower supplies half the electricity
used on the West Coast

U S I N G T I D E S A N D W AV E S
T O P R O D U C E E L E C T R I C I T Y

• Produce electricity from flowing water
– Coastal bays and estuaries

• Tidal energy dams
– France, Nova Scotia, and South Korea

• Challenges
– Few suitable sites

– High costs

– Equipment damage from storms and
saltwater corrosion

WILL HYDROGEN
SAVE US?
• Advantages of hydrogen as a fuel

– Eliminates most outdoor air pollution
from burning fossil fuels

– Would greatly slow climate change
and ocean acidification

WILL HYDROGEN
SAVE US?
• Some challenges

– Hydrogen chemically locked in water and
organic compounds

– Negative net energy

• Serious limitation

– Fuel cells are costly

– CO2 emissions depend on method of
hydrogen production

SHIFTING TO A NEW ENERGY
ECONOMY

• China and the United States
– Key players in making the shift to a new set of

energy resources

– Each country uses about 20% of the world’s energy

• Important actions to enable energy shift
– Use full-cost pricing

– Tax carbon emissions

SHIFTING TO A NEW ENERGY
ECONOMY
• Important actions (cont’d.)

– Decrease and eliminate government subsidies for fossil fuel industries

– Establish a national feed-in-tariff system

– Mandate that a certain percentage of electricity generated by utility companies be from renewable
resources

– Increase government fuel efficiency standards

Plate Tectonics

Lecture 11

What Are the Earth’s
Major Geological
Hazards?

´ Dynamic processes move matter
within the earth and on its surface
´ Cause volcanic eruptions,

earthquakes, tsunamis, erosion,
and landslides

Plate Tectonics

´ Unified theory: Study the dynamic
creation, movement, and destruction
processes of plates

´ Plates: lithosphere fragments

´ Plates move in relation to each other
at varied rates

´ No major tectonic movements within
plates

´ Dynamic actions concentrated along
plate boundaries

3 major types of plate boundaries

 Divergent: plates moving apart and new
lithosphere produced in mid-oceanic ridge

 Convergent: plates collide, subduction
and mountain building

 Transform: two plates slide past one
another

The Earth Beneath Your Feet Is Moving

Divergent Margins and the Red Sea

Figure 2.21
Seafloor Spreading

Convergent Margins
When plates collide

´Continent-Continent

´Ocean-Ocean

´Ocean-Continent

Transform Faults

Transform Margins along the Seafloor

San Andreas
fault

Driving Mechanism
´ What drives plate motion?

´ Old idea: plates are dragged atop a convecting
mantle.

´Convection does occur; not the prime driving
mechanism.

´ Modern thinking: two other forces drive plate motions.
´ Ridge-push—elevated MOR pushes lithosphere away.

´ Slab-pull—gravity pulls a subducting plate downward.

Volcanoes Release
Molten Rock from
the Earth’s Interior

´ Volcano
´Magma rising through the

lithosphere reaches the earth’s
surface through a crack (fissure)

´Eruption–release of lava, hot ash,
and gases into the environment

• ~1500 active volcanoes on Earth

• 400 erupted in the last century

• ~50 eruptions per year

• Most activity concentrated along
major plate boundaries

• Impact risks depend on the type of
volcano

Introduction

www.worldatlas.com

Viscosity of Magma and Explosiveness

Silicon-oxygen tetrahedron

Hot Spots

´ Volcanic centers with magma source
from deep mantle, perhaps near the
core-mantle boundary

´ A chain of volcanoes over a stationary
hot spot

´ The bend of a seamount chain over a
hot spot representing the change of
plate motion

What are Earthquakes?

Faulting

´Occurs when rock breaks
accompanied by displacement

´Occurs along zones of
weakness in the crust, fault
zones

´Fault lines
´Begin as sudden ruptures, but

can result in large (hundreds of
km) faults over millions of year

21
© 2011 Pearson
Education, Inc.

Faulting

´Earthquakes
´Vibration in Earth resulting from

sudden displacement along a fault

´Earthquake waves
´Energy released by earthquakes

moves in several types of seismic
waves that originate at the center of
fault motion, the origin

´Ground above origin experiences
strongest jolt, the epicenter

© 2011 Pearson
Education, Inc.

Body Waves: P and S waves

´ Body waves
´ P or primary waves

´fastest waves
´travel through solids, liquids, or gases
´compressional wave, material

movement is in the same direction as
wave movement

´ S or secondary waves
´slower than P waves
´travel through solids only
´shear waves – move material

perpendicular to wave movement

Surface Waves: R and L waves

´ Surface Waves
´ Travel just below or along the ground’s surface
´ Slower than body waves; rolling and side-to-side

movement
´ Especially damaging to buildings

Surface Waves: R and L waves

´ L-waves (Love waves)
´Waves that intersect the land surface
´Move the ground back and forth like a

writhing snake

´ R-waves (Rayleigh waves)
´ Waves that intersect the land surface
´ Particles underground follow a circular

path as the wave passes
´ Cause the ground to ripple up and down

Where Do Earthquakes Occur and How Often?
~80% of all earthquakes occur along the “Ring of Fire”

Earthquakes Are Geological Rock-and-Roll
Events

´ Richter scale
´Insignificant: <4.0
´Minor: 4.0–4.9
´Damaging: 5.0–5.9
´Destructive: 6.0–6.9
´Major: 7.0–7.9
´Great: >8.0

´ Largest recorded: 9.5 in Chile,
1960

Tsunamis

Earthquakes on the Ocean Floor Can
Cause Tsunamis

´ Tsunami
´Series of huge waves generated when ocean floor

suddenly rises or drops
´Travels several hundred miles per hour

´Slows down as it approaches coastline
´ December 2004–Indian Ocean tsunami

´Magnitude 9.15 earthquake
´Over 230,000 people lost their lives

´No warning system in place

Earthquakes on the Ocean Floor Can
Cause Tsunamis

Where they Occur

(Setake and Atwater, 2007)

N O N
R E N E W A B L E E N E R G Y

R E S O U R C E S

L E C T U R E 1 3

WHAT T YPES OF ENERGY RESOURCES
DO WE USE?

90% of the commercial energy
used in the world comes from

nonrenewable resources

• Oil, natural gas, and coal

Energy resources vary greatly
in their net energy

• Amount of energy available
from a resource minus the
amount of energy needed to
make it available

WHERE DOES THE ENERGY WE USE
COME FROM?

N ET E N E R G Y : I T TA K E S
E N E R G Y T O G ET E N E R G Y

• Each step in making energy available uses
high-quality energy

– Example: oil must be found, pumped,
transferred to a refinery, converted to
gasoline, and delivered to consumers

• Net energy yield
– Amount of high-quality energy available from a

resource minus the high-quality energy
needed to make the energy available

NET ENERGY: IT TAKES ENERGY TO
GET ENERGY
• Net energy ratio

– Also called energy returned on investment

– Energy obtained per unit energy used to obtain it

• Energy density
– Amount of energy available per kilogram of the

resource

NET ENERGY: IT TAKES ENERGY TO GET ENERGY

WE DEPEND HEAVILY
ON OIL
• Crude oil (petroleum)

– Contains combustible hydrocarbons

• Peak production
– Time after which production from a well declines

• Crude oil cannot be used as it comes out of the ground
– Must be refined using high-quality energy

– Petrochemicals–byproducts

WE DEPEND HEAVILY ON OIL

IS THE WORLD RUNNING OUT OF
CRUDE OIL?

• Proven oil reserves–available deposits
– 12 OPEC countries have 82% of the world’s proven crude

oil reserves

• These countries play a role in regulating global prices by
agreeing to increase or decrease the amount produced

• Increasing shortage of cheap oil
– Easy-to-reach deposits are quickly being depleted

O I L P R O D U C T I O N A N D
C O N S U M P T I O N I N T H E
U N I T E D S T AT E S

 U.S. commercial energy sources

• 80% from fossil fuels

• Largest portion comes from crude oil

 U.S. oil consumption exceeds domestic
production

• Must import oil

 Recent rise in domestic production of tight
oil from shale rock

• Likely to peak around 2020 and then
decline

USE OF HEAV Y OIL HAS A HIGH
ENVIRONMENTAL IMPACT

• Shale oil
– Oil that is integrated within bodies of shale rock

• As opposed to being trapped between layers of
rock

– Production involves mining, crushing, and heating
the rock

• Extracts kerogen that can be distilled

USE OF HEAV Y OIL HAS A HIGH
ENVIRONMENTAL IMPACT

• Oil sands (tar sands) another source of heavy oil
– Contains bitumen

– Extensive deposits in Canada

• Extraction
– Clear-cutting forests and strip-mining the land

– Drilling vertical wells

– Low net energy yield

– Requires much water

– Emits pollutants

NATURAL GAS IS A VERSATILE AND
WIDELY USED FUEL
• Liquefied petroleum gas (LPG)

– Stored in pressurized tanks for use in rural areas

• Liquefied natural gas (LNG)
– Can be transported across oceans

– Medium net energy yield

– The United States currently exports to other nations

ENVIRONMENTAL EFFECTS OF NATURAL
GAS PRODUCTION AND FRACKING IN
THE U.S.
• Fracking has several harmful environmental

effects
– Requires enormous volumes of water

– Produces hazardous wastewater
• Earthquakes could release wastewater into

groundwater

– Failure of well-casing cement causes
contaminated ground water

• Natural gas fracking excluded from EPA
regulations in 2005

CAN NATURAL GAS HELP TO SLOW
CLIMATE CHANGE?

• Emits less CO2 per unit of energy than coal
• Low price could slow shift to other renewable

energy resources

• Methane a much more potent greenhouse gas than
CO2

– Drilling, production, and distribution of natural gas
releases large quantities of methane

COAL IS A PLENTIFUL BUT DIRT Y FUEL

• Coal
– Solid fossil fuel formed from remains of

land plants

• Burned in power plants
– Generated 37% of the world’s electricity

in 2017

• Largest consumers of coal
– China, India and the United States,

COAL IS A PLENTIFUL BUT DIRT Y FUEL

COAL IS A PLENTIFUL
BUT DIRT Y FUEL
• Environmental costs of burning coal

– Mining coal severely degrades land

– Water and air pollution

• Soot and CO2
• Trace amounts of mercury and radioactive materials

– Scrubbers remove some pollutants before they leave
smokestacks

• Produces coal ash that must be safely stored

WE ARE NOT PAYING THE FULL COST
OF USING COAL

• Harmful environmental and health costs
– Not included in market price of coal-generated

electricity

• Ways to implement full-cost pricing
– Phase out subsidies and tax breaks

– Require stricter air pollution controls

– Tax CO2 emissions

– Regulate coal ash as a hazardous waste

THE FUTURE OF
COAL
• U.S. coal use dropped 18% between 2007

and 2013
– Increased competition from natural gas,

wind, and solar power

– Grassroots political opposition

• Natural gas should overtake coal as largest
electricity source by the 2030s

• U.S. coal producers are exporting coal
– Use is expanding in India, China and other

countries in Africa and Asia

W E C A N C O N V E R T C O A L
I N T O G A S E O U S A N D
L I Q U I D F U E L S

• Conversion of solid coal to synfuels
– Synthetic natural gas (SNG) by coal

gasification

– Methanol or synthetic gasoline by coal
liquefaction

• Producing synfuels requires mining of 50%
more coal

– Lower net energy and cost more to
produce than coal

HOW DOES A NUCLEAR FISSION
REACTOR WORK?

• Controlled nuclear fission reaction in a reactor
– Light-water reactors

– Boil water to produce steam to spin a turbine

– Fueled by uranium ore mined from the earth’s
crust

• Enriched uranium packed as pellets in fuel rods
and fuel assemblies

– Control rods absorb neutrons

HOW DOES A NUCLEAR FISSION
REACTOR WORK?
• Water is the usual coolant
• Containment shell around the core for

protection

• Emergency core cooling system
• Typical cost to construct

– $9–27 billion

• United States, France, China and Russia
– Leading producers of nuclear power in 2017

W H AT I S T H E
N U C L EA R F U EL
C Y C L E?
• Mining the uranium
• Processing and enriching the

uranium to make fuel

• Using it in a reactor
• Safely storing the radioactive waste
• Retiring the worn-out plant

– Storing its high- and moderate-level
radioactive parts safely

DEALING WITH RADIOACTIVE
NUCLEAR WASTES

• Rods must be replaced every three to four
years

• Stored in water-filled pools for several years to
cool

• Transferred to dry casks
• Can be processed to remove plutonium

– Reprocessing reduces storage time from
240,000 years to about 10,000 years

– Costly and produces weapons material

D E A L I N G W I T H
R A D I O A C T I V E N U C L E A R
W A S T E S

• No permanent, secure
repository exists today

• Retiring nuclear plants
• Enormous costs

CONTROVERSY ABOUT THE
FUTURE OF NUCLEAR POWER

• Nuclear reactors produced 20% of U.S. electricity in
2017 and 9% energy

• 59 new nuclear reactors under construction worldwide
in 2018

• U.S. government provides subsidies, tax breaks, and
insurance for the nuclear industry

• Accidents have dampened public confidence in nuclear
power

CONTROVERSY ABOUT THE FUTURE
OF NUCLEAR POWER
• New technologies

– Advanced light-water reactors

• Built-in safety features

– Smaller, modular light water reactors

• Not yet built and evaluated

– Thorium-based reactors

• Less costly and safer

WATER RESOURCES

Lecture 14

WHY SHOULD YOU CARE
ABOUT WATER RESOURCES?

Humans and environment
depend on water

– Life made primarily of water
– Survival without water a few days
– Industry and agriculture use large

amounts

Water unevenly distributed on
earth

– Too much floods
– Too little becomes main focus of life

-Low cost encourages waste

WE ARE MANAGING FRESHWATER POORLY

• Access to freshwater a global health issue
− An average of 9,300 people die each day from lack of access

to safe drinking water

• Economic issue
− Water vital for producing food and energy

• National and global security issue

• Environmental issue
− Excessive withdrawal

THE EARTH’S WATER SUPPLY

• LIQUID WATER COVERS 3/4 SURFACE

– MOST SALTWATER

– AVAILABLE LIQUID FRESHWATER 0.024% OF TOTAL

– SURFACE WATER (LAKES, RIVERS AND STREAMS)

– GROUNDWATER

• HYDROLOGIC CYCLE

-MOVEMENT OF WATER IN THE SEAS, LAND, AND AIR

-DISTRIBUTED UNEVENLY

• HUMANS ALTER THE HYDROLOGIC CYCLE

-WITHDRAWING AND POLLUTING WATER AND CAUSING CLIMATE CHANGE

GROUNDWATER

• ZONE OF SATURATION
• SPACES IN SOIL BELOW A CERTAIN DEPTH ARE

FILLED WITH WATER

• WATER TABLE
• TOP OF ZONE OF SATURATION

• AQUIFERS
• RECHARGED NATURALLY BY PRECIPITATION OR BY

NEARBY LAKES, RIVERS, AND STREAMS

SURFACE WATER

• SURFACE WATER
• SURFACE RUNOFF

• WATERSHED OR DRAINAGE BASIN

WATER USE IS INCREASING

• TWO-THIRDS OF SURFACE RUNOFF LOST TO SEASONAL
FLOODS

• RELIABLE RUNOFF
• REMAINING ONE-THIRD IS RELIABLE SOURCE OF

FRESHWATER

• WORLDWIDE AVERAGES
• IRRIGATION FOR CROPS AND LIVESTOCK: 70%
• INDUSTRIAL USE: 20%
• CITIES AND RESIDENCES: 10%

• WATER FOOTPRINT
• VOLUME OF WATER USED DIRECTLY OR INDIRECTLY

WATER USE IS INCREASING
• VIRTUAL WATER

– WATER USED TO PRODUCE FOOD AND OTHER PRODUCTS

CASE STUDY:
FRESHWATER RESOURCES

IN THE UNITED STATES

• MORE THAN ENOUGH RENEWABLE
FRESHWATER

-UNEVENLY DISTRIBUTED AND
POLLUTED

THE COLORADO RIVER BASIN
• RUNS THROUGH DRY SOUTHWESTERN

U.S.

– 14 MAJOR DAMS

– MOST WATER REMOVED

– ELECTRICITY

– IRRIGATION

– PUBLIC WATER

– 15% OF U.S. FOOD PRODUCTION
AND 13% LIVESTOCK

– FLOW GREATLY DECREASED

– SILTATION

FRESHWATER SHORTAGES WILL GROW

• MANY OF THE WORLD’S MAJOR RIVER SYSTEMS ARE HIGHLY STRESSED
• NILE, JORDAN, YANGTZE, AND GANGES

• MORE THAN 30 COUNTRIES FACE FRESHWATER SCARCITY
• ESTIMATE: 60 COUNTRIES BY 2050

• 30% OF THE EARTH’S LAND AREA EXPERIENCES SEVERE DROUGHT
• RESEARCH PREDICTS THIS WILL WORSEN

GROUNDWATER DEPLETION

• GROUNDWATER WITHDRAWALS UNSUSTAINABLE IN SOME AREAS
• BEING PUMPED FROM AQUIFERS IN SOME AREAS FASTER THAN IT IS RENEWED BY

PRECIPITATION

• WIDESPREAD DRILLING OF WELLS BY FARMERS
• ACCELERATED AQUIFER OVERPUMPING
• WATER TABLES FALLING

• IN 2008, SAUDI ARABIA ANNOUNCED THAT

IT HAD DEPLETED ITS MAJOR DEEP AQUIFER

OVERPUMPING OF THE OGALLALA AQUIFER

• OGALLALA AQUIFER—LARGEST KNOWN
AQUIFER

• IRRIGATES THE GREAT PLAINS

• VERY SLOW RECHARGE

• WATER TABLE DROPPING
• WATER PUMPED 10–40 TIMES FASTER

THAN RECHARGE RATE

• GOVERNMENT FARM SUBSIDIES RESULT
IN FURTHER DEPLETION

• BIODIVERSITY THREATENED IN SOME
AREAS

OVERPUMPING AQUIFERS CAN HAVE HARMFUL
EFFECTS

• LIMITS FOOD PRODUCTION AND RAISES PRICES

• WIDENS GAP BETWEEN RICH AND POOR

• LAND SUBSIDENCE
• SAN JOAQUIN VALLEY IN CALIFORNIA
• MEXICO CITY

• GROUNDWATER OVERDRAFTS NEAR COASTAL REGIONS
• CONTAMINATION OF GROUNDWATER WITH

SALTWATER

DEEP AQUIFERS MIGHT BE TAPPED

• MAY CONTAIN ENOUGH WATER TO
PROVIDE FOR BILLIONS OF PEOPLE FOR
CENTURIES

• MAJOR CONCERNS
• NONRENEWABLE
• LITTLE IS KNOWN ABOUT THE GEOLOGICAL

AND ECOLOGICAL IMPACTS OF PUMPING
DEEP AQUIFERS

• NO INTERNATIONAL TREATIES GOVERN
ACCESS

• COSTS OF TAPPING ARE UNKNOWN
• WATER IS CONTAMINATED

HOW CAN WE INCREASE FRESHWATER SUPPLIES?

• LARGE DAM-AND-RESERVOIR SYSTEMS
• GREATLY EXPANDED WATER SUPPLIES IN SOME

AREAS

• DISRUPTED ECOSYSTEMS AND DISPLACED PEOPLE

• MAIN GOAL OF A DAM AND RESERVOIR SYSTEM
• CAPTURE AND STORE RUNOFF
• RELEASE RUNOFF AS NEEDED FOR:

• FLOOD CONTROL
• GENERATING ELECTRICITY
• SUPPLYING IRRIGATION WATER
• RECREATION (RESERVOIRS)

LARGE DAMS PROVIDE BENEFITS AND CREATE
PROBLEMS

• RESERVOIRS

• INCREASE THE RELIABLE RUNOFF AVAILABLE FOR USE (33%)

• DISPLACE PEOPLE (40-80MILLION)

• IMPAIR ECOLOGICAL SERVICES OF RIVERS (NUTRIENT CYCLING, CLIMATE
MODERATION, WASTE TREATMENT, GROUNDWATER RECHARGE, HABITAT)

• ENDANGER PLANT AND ANIMAL SPECIES (1 OUT OF 5 SPECIES)
• FILL UP WITH SEDIMENT WITHIN 50 YEARS
• GLACIERS FEEDING THE RIVERS ARE MELTING FAST

WATER TRANSFERS

• TRANSFERRING WATER FROM ONE PLACE TO ANOTHER HAS
GREATLY INCREASED WATER SUPPLIES IN SOME AREAS

-HAS ALSO DISRUPTED ECOSYSTEMS

• WATER TRANSFERRED FROM WATER-RICH TO POOR REGIONS
– CANALS AND PIPELINES

– BENEFITS WHERE WATER TRANSFERRED

-WATER LOSS THROUGH EVAPORATION AND LEAKS

– ECOSYSTEMS CHANGE BOTH PLACES

– CALIFORNIA WATER PROJECT

– SACRAMENTO RIVER DEGRADED

– POLLUTION PROBLEMS

CASE STUDY: THE ARAL SEA DISASTER

• LARGE-SCALE WATER TRANSFERS IN DRY CENTRAL ASIA HAVE LED TO:
• WETLAND DESTRUCTION

• DESERTIFICATION
• GREATLY INCREASED SALINITY
• FISH EXTINCTIONS AND DECLINE OF FISHING
• BLOWING SALT AND DUST DESTROYING WILDLIFE AND CROPS
• INCREASED GLACIAL MELTING IN THE HIMALAYAS

CASE STUDY: THE ARAL SEA DISASTER

• SHRINKAGE OF THE ARAL SEA HAS ALTERED LOCAL
CLIMATE

• HOT, DRY SUMMERS, COLDER WINTERS, AND A
SHORTENED GROWING SEASON

• RESTORATION EFFORTS
• COOPERATION OF NEIGHBORING COUNTRIES
• MORE EFFICIENT IRRIGATION
• DIKE CONSTRUCTION RAISED LEVEL OF

NORTHERN SEA BY 2 METERS

• SOUTHERN SEA MAY DRY UP WITHIN FEW
YEARS

DESALINATING SEAWATER

OCEAN WATER ABUNDANT

– REMOVAL OF SALT = FRESHWATER

– DISTILLATION OR REVERSE OSMOSIS

– CURRENTLY <1% OF FRESHWATER FOR THE WORLD AND U.S.

– PROBLEMS

– VERY EXPENSIVE

– HIGH ENERGY USE

– DISPOSAL OF SALTY WATER

– MOSTLY IN MIDDLE EAST, NORTH AFRICA,

CARIBBEAN, AND MEDITERRANEAN

(18, 400 ACROSS THE WORLD)

CONSERVING WATER

• WAYS TO USE FRESHWATER MORE SUSTAINABLY
– 66% OF WATER WASTED

– RAISE WATER PRICES

– SHIFT WATER SUBSIDIES

– INCREASE IRRIGATION EFFICIENCY.

– NIGHT IRRIGATION

– SEVERAL CROPS TOGETHER

– MORE WATER-EFFICIENT CROPS

– IMPORT WATER-DEMANDING CROPS

– USE TREATED WASTEWATER

– CONSERVE WATER IN INDUSTRY

– CONSERVE WATER IN HOMES

WHAT WOULD YOU DO?

• WAYS TO REDUCE WATER USE

– SHORT SHOWERS

– WASH FULL LAUNDRY LOADS

– DRIP IRRIGATION

– FIX LEAKS

– WATER SAVING DEVICES

– DON’T RUN WATER WHEN NOT USING

– REDUCE MEAT AND WATER RICH FOOD CONSUMPTION

– REPLACE LAWNS WITH LOW-WATER PLANTS

– WASH CAR BY HAND

ATMOSPHERE AND
AIR POLLUTION

Lecture 15

WHY IS THE
ATMOSPHERE SO
IMPORTANT?

WHAT IS THE NATURE OF THE
ATMOSPHERE?

Atmosphere: Thin layers of gases surrounding the
earth

Layers defined largely by differences in
temperature

Innermost layers of the atmosphere:
­ Troposphere
­ Supports life

­ Stratosphere
­ Contains the protective ozone layer

THE ATMOSPHERE CONSISTS OF SEVERAL LAYERS

Density and pressure play major roles in weather

Density
• Number of gas molecules per unit of air volume
• Decreases with higher altitude

Atmospheric pressure
• Measure of the weight of molecules above you (Force per unit area of a column of air)
• Decreases with higher altitude

AIR MOVEMENT AND CHEMICALS IN THE TROPOSPHERE
AFFECT THE EARTH’S WEATHER AND CLIMATE

Troposphere
­ 75–80% of the earth’s air mass
­ Closest to the earth’s surface

Two primary gas types
­ Permanent

­ Oxygen and Nitrogen

­ Variable
­ Water Vapor
­ Carbon Dioxide

Permanent gases make up over 95% of
total atmosphere

THE STRATOSPHERE IS OUR GLOBAL SUNSCREEN
Stratosphere: 17–48 kilometers above the earth’s
surface
­ Similar composition to troposphere except:
­ Higher concentration of ozone (O3)

Ozone layer
­ Filters 95% of harmful UV radiation
­ Allows life to exist on land

WATER H2O,
THE MOST IMPORTANT VARIABLE GAS

0-4% in atmosphere

Varies with temperature and location

Greenhouse Gas (GHG)

Only GHG which absorbs both incoming
and outgoing radiation

CARBON DIOXIDE CO2
0.04% concentration

Seasonably Variable

GHG

Natural and Human produced

Absorbs outgoing radiation

WHAT IS THE GREENHOUSE EFFECT AND HOW
DOES IT WORK?

GREENHOUSE EFFECT

Natural process which enables life
on Earth

Earth thermal radiation held in by
greenhouse gases

Atmospheric blanket

AIR POLLUTION COMES FROM
NATURAL AND HUMAN SOURCES

Natural sources
­ Wind-blown dust
­ Pollutants from wildfires or volcanic

eruptions
­ Volatile organics released by plants

Human sources
­ Mostly in industrialized and urban areas
­ Stationary sources
­ Power plants and industrial facilities

­ Mobile sources
­ Motor vehicles

AIR POLLUTANTS

Air pollution–presence of chemicals
in the atmosphere
­ Concentrations high enough to harm

organisms, ecosystems, human-made
materials, or alter climate

Primary pollutants
­ Emitted directly into the air

Secondary pollutants
­ Formed from reactions of primary

pollutants

ATMOSPHERIC
BROWN CLOUDS

Atmospheric brown clouds
­ Particles of dust, smoke, ash, soot
­ Caused by wind erosion, fire
­ Found throughout Asia and the western Pacific

Pollutions travels to remote areas
­ Absorbed into glaciers

MAJOR OUTDOOR AIR
POLLUTANTS

Carbon oxides
­ Carbon monoxide (CO) and carbon

dioxide (CO2)
­ Some sources of CO are cars, burning

forests and grasslands, and fossil fuel
burning power plants
­ Some sources of CO2 include natural

carbon cycle and burning of fossil fuels

MAJOR OUTDOOR AIR
POLLUTANTS

Nitrogen oxides and nitric acid
­ Nitrogen dioxide (NO2 ) reacts with

water vapor in atmosphere to form nitric
acid and nitrate salts, part of acid
deposition
­ Some sources are fertilizer and burning

of fossil fuels
­ NO and NO2 play a role in the

formation of photochemical smog, a
mixture of chemicals formed under the
influence of sunlight in cities with heavy
traffic.
­ Nitric acid HNO3 , secondary pollutant

and a major component of acid rain.

MAJOR OUTDOOR AIR
POLLUTANTS

Sulfur dioxide and sulfuric acid
­ One-third of sulfur dioxide and sulfuric acid are from

natural sources, such as volcanoes
­ Other sources include combustion of coal and oil

refining
­ Reduce visibility and aggravate breathing problems,

damage crops, corrode metals, and damage stone

MAJOR OUTDOOR AIR
POLLUTANTS

Particulates
­ Suspended particulate matter (SPM)–

variety of solid particles and liquid
droplets that are small and light
enough to remain suspended in the air
for long periods
­ About 62% of the SPM in outdoor air

comes from natural sources such as
dust, wildfires, and sea salt
­ The other 38% comes from human

sources, such as coal-burning power
and industrial plants

MAJOR OUTDOOR AIR
POLLUTANTS

Ozone

•One of the major ingredients of
photochemical smog

•Can cause coughing and breathing problems

•Ozone in the troposphere can be harmful at
high enough levels and ozone in the
stratosphere is beneficial because it protects
us from harmful UV radiation

•Human activities have decreased the amount
of beneficial ozone in the stratosphere
and increased the amount of harmful
ground-level ozone

MAJOR OUTDOOR AIR
POLLUTANTS

Volatile organic compounds
(VOCs)
­ Organic compounds that exist as gases

in the atmosphere or that evaporate
from sources on the Earth’s surface into
the atmosphere
­ Example: Methane from rice paddies,

landfills, natural gas wells and
pipelines, and from cows

LEAD: A HIGHLY TOXIC
POLLUTANT

In air, water, soil, plants,
and animals

Does not break down in the
environment

Impacts human health and
environment
­ Children most vulnerable
­ Can cause death, brain damage,

and paralysis

Lead exposure for adults
and children working in e-
waste recycling

BURNING COAL PRODUCE
INDUSTRIAL SMOG

Chemical composition of
industrial smog
­ Sulfur dioxide, sulfuric acid, and

suspended solid particles

Combustion of coal and oil
forms carbon monoxide,
carbon dioxide, and soot

Common in industrialized
urban areas
­ Examples: China, India, Ukraine
­ Beijing air quality among world’s

worst

SUNLIGHT PLUS CARS EQUALS
PHOTOCHEMICAL SMOG

Photochemical smog formed
under the influence of sun’s
UV radiation

VOCs + NOx + heat +
sunlight yields:
­ Ground level O3 and other

photochemical oxidants
­ Aldehydes
­ Other secondary pollutants

SEVERAL FACTORS AFFECT LEVELS
OF OUTDOOR AIR POLLUTION

Natural factors that help
reduce outdoor air pollution
­ Gravity allows particulates to

settle
­ Rain and snow
­ Salty sea spray from the ocean
­ Winds
­ Natural chemical reactions

remove some pollutants

SEVERAL FACTORS AFFECT LEVELS
OF OUTDOOR AIR POLLUTION

Factors that increase outdoor
air pollution
­ Urban buildings
­ Hills and mountains
­ High temperatures
­ VOC emissions from certain trees

and plants
­ The grasshopper effect
­ Temperature inversion
­ Warm air above cool air prevents mixing

ACID DEPOSITION

Human-generated NOx and
SOx in the atmosphere

Wet deposition
­ Acidic rain, snow, fog, or cloud vapor

Dry deposition
­ Acidic particles

Substances remain in the
atmosphere for 2–14 days

HARMFUL EFFECTS OF ACID DEPOSITION

Contributes to respiratory disorders

Releases toxic metals from soils and rocks
­ Bioaccumulation in fish

Lowers pH in aquatic ecosystems

Leaches soil nutrients

Damages forests

Damages statues and buildings

INDOOR AIR POLLUTION IS A SERIOUS PROBLEM
Less-developed countries
­ Indoor burning of wood, charcoal, dung, crop

residues, and coal
­ Greatest risk to low-income populations

More-developed countries
­ Tobacco smoke
­ Formaldehyde
­ Radioactive radon-222 gas

HEALTH EFFECTS OF AIR
POLLUTION

Air pollution can contribute
to
­ Asthma
­ Chronic bronchitis
­ Emphysema
­ Lung cancer
­ Heart attack
­ Stroke

YOUR BODY’S NATURAL AIR POLLUTION
DEFENSES CAN BE OVERWHELMED

125,000 people develop
cancer in the United States
each year from breathing
diesel fumes

14% of the U.S. population
exposed to excessive
particulate pollution levels
daily

LAWS AND REGULATIONS CAN REDUCE OUTDOOR
AIR POLLUTION
United States
­ Clean Air Acts: 1970, 1977, and 1990 created regulations enforced by states and cities

EPA
­ Established air quality standards for six outdoor pollutants
­ Carbon monoxide, nitrogen dioxide, sulfur dioxide, suspended particulate matter, ozone, and lead

LAWS AND REGULATIONS CAN REDUCE OUTDOOR AIR
POLLUTION

EPA’s national emission standards for 188 hazardous air pollutants (HAPs) mostly
includes VOC’s, organic hydrocarbons and toxic metals
­ Toxic Release Inventory (TRI) (1990) requires factories, power plants, mines and chemical manufacturers

to report their release and waste management methods.

New U.S. regulations
­ Limit CO2 emissions from coal-fired power plants

New air quality standards in China
­ Ban on high-sulfur, high-ash-content coal in major cities

2018: Policy changes considered by EPA likely to lead to less healthy air

USING THE MARKETPLACE TO
REDUCE OUTDOOR AIR POLLUTION

Buy and sell air pollution
allotments in the
marketplace
­ 1990 Clean Air Act authorized

emissions trading or cap-and-
trade program
­ Success depends on:
­ How low initial cap is set

­ How often it is lowered

WAYS TO REDUCE OUTDOOR AIR POLLUTION

Technologies used on coal-burning power
plants
­ Electrostatic precipitator
­ Wet scrubber

Motor vehicle pollution
­ Prevention and reduction

REDUCING INDOOR AIR
POLLUTION

Greater threat to human
health than outdoor pollution

What can be done?
­ Prevention
­ Cleanup

THE USE OF CERTAIN CHEMICALS
THREATENS THE OZONE LAYER

Ozone is thinning over
Antarctica and the Arctic

Chlorofluorocarbons (CFCs)
­ Persistent chemicals that attack ozone

in the stratosphere

WHY SHOULD WE WORRY ABOUT OZONE
DEPLETION?

Ozone protects the earth’s surface from
damaging UV radiation
­ Human health concerns
­ UV radiation affects plankton

REVERSING STRATOSPHERIC OZONE DEPLETION

Stop producing ozone-depleting chemicals immediately
­ Will take at least 60 years to recover to 1980 levels

Agreements with a prevention approach
­ Montreal Protocol
­ Cut emissions of CFCs

­ Copenhagen Amendment
­ Accelerated phase-out of CFCs

WATER
POLLUTION

Lecture 16

HUMANS AND MUCH OF LIFE DEPENDS ON WATER

– ABUNDANT BUT FINITE SUPPLY

– CONTINUALLY RECYCLED AND PURIFIED

WATER POLLUTION

– CHANGE IN WATER WITH HARM TO HUMANS OR OTHER
ORGANISMS

MAJOR THREAT TO HUMAN HEALTH

SPREAD OF DISEASE

TOXIC MATERIALS

WHY SHOULD YOU CARE
ABOUT WATER POLLUTION?

THE EARTH’S WATER SUPPLY

WATER COVERS ABOUT 73% EARTH SURFACE

– 0.024% OF TOTAL WATER AVAILABLE

– REMAINDER SALTY, TOO DEEP OR FROZEN

– 30% AVAILABLE FRESHWATER IN AQUIFERS

– HALF WORLD DRINKING WATER

– 25% WATER USED IN U.S.

 WATER NOT EVENLY DISTRIBUTED

MANY DON’T HAVE ACCESS TO ENOUGH

WATER HABITAT FOR MANY ORGANISMS

– AQUATIC LIFE ZONES

– MARINE AQUATIC SYSTEMS

– – FRESHWATER AQUATIC SYSTEMS

 LAYERS OF WATER DIFFERENT PROPERTIES

– UPPER WARMER WITH LIGHT

– MIDDLE SOME LIGHT, COLDER

– DEEPER DARK, COLD

– DISSOLVED OXYGEN

WATER AS HABITAT

MARINE AQUATIC SYSTEMS

LARGEST AQUATIC SYSTEM

 FOUR OCEANS

– PACIFIC (LARGEST)

– ATLANTIC

– ARCTIC

– INDIAN

MARINE ZONES

– COASTAL ZONE

– OPEN SEA

– OCEAN BOTTOM

FRESHWATER AQUATIC
SYSTEMS

TWO TYPES

STANDING BODIES

– LAKES, PONDS

– INLAND WETLANDS

– HIGH BIODIVERSITY

– ABSORB WATER

– MANY FORMED BY GLACIERS

– CLASSIFIED BY AMOUNTS OF
NUTRIENTS

• EUTROPHIC OR OLIGOTROPHIC

FRESHWATER AQUATIC SYSTEMS

FLOWING SYSTEMS

– RIVERS AND STREAMS

– WATERSHED OR DRAINAGE BASIN

– SOURCE ZONE

– TRANSITION ZONE

– FLOODPLAIN ZONE

WHAT ARE THE PROBLEMS?
HUMAN IMPACTS ON NATURAL CYCLES

THREE MAJOR IMPACTS

1. FRESHWATER TAKEN FROM STREAMS, LAKES, AND
AQUIFERS

– OFTEN FASTER THAN REPLACEMENT

2. CLEAR LAND AND MAKE IMPERMEABLE TO WATER

– FASTER RUNOFF

– SLOWER RECHARGE OF AQUIFERS

3. DRAINING AND FILLING WETLANDS

– NATURAL “SPONGES”

– RUNOFF INCREASES

 SUBSTANCES DUMPED INTO WATER
CAN REDUCE USEFULNESS

– DRINKING, FISHING, SWIMMING,
IRRIGATING & OTHER USES OF WATER

POLLUTANT SOURCE

– POINT

– NONPOINT

SOURCES OF
WATER POLLUTION

POLLUTION OF RIVERS LAKES

 HALF OF WORLD’S 500 RIVERS HEAVILY POLLUTED

– UNTREATED SEWAGE

– INDUSTRIAL WASTE

 DEVELOPING COUNTRIES

• CHINA’S RIVERS

-1/2 CAN’T BE USED FOR ANY PURPOSE

• INDIA’S RIVERS

-275 OUT OF 445 SEVERELY POLLUTED

 WATER POLLUTION OFTEN REVERSIBLE

– REMOVE SOURCE OF POLLUTION

– BIODEGRADABLE POLLUTANTS

– NONBIODEGRADABLE

POLLUTION OF LAKES

LAKES AND RESERVOIRS LESS EFFECTIVE AT DILUTING
POLLUTANTS THAN STREAMS

-STRATIFIED LAYERS WITH LITTLE VERTICAL MIXING

-LITTLE OR NO WATER FLOW

-CAN TAKE UP TO 100 YEARS TO FLUSH AND CHANGE
THE WATER IN A LAKE

-BIOLOGICAL MAGNIFICATION OF POLLUTANTS

OCEAN POLLUTION

37% WORLD 40% U.S. LIVE NEAR SEA

– HUMAN IMPACTS ON OCEAN WATERS

– 80-90% LESS DEVELOPED COUNTRIES SEWAGE
DIRECTLY DUMPED

 EXCESS NUTRIENTS

– MICROBES

– OXYGEN-DEMANDING WASTES

– OXYGEN DEPLETED ZONES

OCEAN POLLUTION

 EXCESS NUTRIENTS
– OXYGEN DEPLETED “DEAD” ZONES
– MISSISSIPPI RIVER DISCHARGE

 CORAL REEFS VERY SUSCEPTIBLE
– SLOW GROWTH
– FAIRLY SHALLOW WATER

 OIL POLLUTION
– LARGE AND SMALL SPILLS
– RUNOFF FROM CITIES

 PLASTIC
– GREAT PACIFIC GARBAGE PATCH

GROUNDWATER POLLUTION

MUCH OF WORLD DEPENDS ON
GROUNDWATER

– DRINKING AND IRRIGATION WATER

POLLUTANTS

– FERTILIZERS, PESTICIDES

– GASOLINE, OIL, PAINT THINNERS

– SEPTIC SYSTEMS

– WASTE PONDS

– UNDERGROUND STORAGE TANKS

WHAT CAN BE DONE?
CLEAN-UP VERSUS PREVENTION

TWO WAYS CLEANUP OR PREVENTION

– PREVENTION BETTER

– ONLY 15% OF OIL SPILLS RECOVERED

– DAMAGE BEFORE CLEANUP

– BETTER REGULATIONS

– GROUNDWATER IS PARTICULARLY HARD TO CLEAN UP

LEGAL MEASURES

WATER POLLUTION MAJOR POLITICAL PROBLEM

– U.S. CLEAN WATER ACT

• PERMISSIBLE POLLUTANT LEVELS

– PERCENT WASTEWATER TREATMENT

• INCREASED FROM 33% TO 75%

– SAFE STREAMS INCREASED 33-60%

– NATIONAL AND INTERNATIONAL LAWS

– OIL TANKERS

TECHNOLOGICAL SOLUTIONS

NONPOINT-SOURCE POLLUTION DIFFICULT

– DIFFICULT TO ENFORCE A LAW

• IDENTIFICATION OF RESPONSIBLE PARTY HARD

• LARGE AREA

– LANDSCAPE APPROACH

• KEEP CROPLAND VEGETATED

• FENCE OUT LIVESTOCK

• WISE USE OF FERTILIZERS

TECHNOLOGICAL SOLUTIONS

WASTEWATER OR SEWAGE TREATMENT PLANTS

• PRIMARY SEWAGE TREATMENT
• PHYSICAL PROCESS

• SECONDARY SEWAGE TREATMENT
• BIOLOGICAL PROCESS USING BACTERIA

• TERTIARY OR ADVANCE SEWAGE TREATMENT
• SPECIAL FILTERING PROCESSES

• BLEACHING AND DISINFECTION

ECONOMIC AND POLITICAL SOLUTIONS

LEGAL REQUIREMENTS OFTEN SPUR TECHNOLOGY

– DISCHARGE TRADING POLICY

– PERMITS FOR DISCHARGE INTO WATERWAYS

– ABILITY TO POLLUTE CAN BE SOLD AND TRADED

– CREATES A MARKET

– CAPS LOWERED EVERY FEW YEARS

WHAT WOULD YOU DO?

Mindful of water use

• use only needed
water

• no dumping of
harmful substances

• no yard waste in
stream

Personal choices

• buy from companies
with good policies

• only activities that
minimize pollution

• use manure or
compost, not
fertilizers

Social activity

• talk about water
pollution

• support politicians
with good policies

• emphasize
preventing pollution