Transcript 32_Review - School of Life Sciences

Announcements – Nov 13
Nov. 15 (Wednesday) - Exam 3
Nov. 17 (Friday) - no class
3rd exam Wed, Nov 15th
• Bring: #2 pencil
Photo ID
Student ID#
NetID (usually 1st part of e-mail)
• Arrive early
• Sit every other seat.
• Neighbors should have different
exams (colored booklets)
Test Format
• 50 questions, multiple choice & T/F
• 2-3 extra credit questions
• 50 minutes
Test Material
• Any thing from lecture or readings
is fair game
• “Points to know”
• Mostly fact-based questions, some
concept application
Assigned Reading
Chapters from Book: 9, 10, 11, 12, 13, 14
Air: Climate and Pollution
Chapter 9
Outline:
• Atmosphere and Climate
• Climate Change
– El Nino
– Human Causes
• Climate and Pollution
– Kinds of Pollution
– Sources
– Transport
• Effects of Air Pollution
• Air Pollution Control
ATMOSPHERE AND CLIMATE
• Weather - A description of short-term physical
conditions of the atmosphere.
• Climate - A description of the long-term weather
pattern in a particular area.
– Weather and climate are primary determinants of
biomes and ecosystem distribution.
Troposphere
• Troposphere
– Ranges in depth from 18 km over the equator to 5 km
over the poles.
– Air circulates in convection currents.
– Air temperature drops rapidly with increasing altitude.
– Contains 75% of total air mass.
• Stratosphere
– Extends from troposphere to about 50 km.
– Similar composition to Troposphere, but much more
dilute.
– Temperature increases with altitude.
– Fraction of water vapor is 1000x less and ozone is
1000x more than in the troposphere.
– Relatively calm
• Mesosphere
– Middle Layer.
• Minimum temperature is about - 80o C.
• Thermosphere
– Ionized gases and high temperatures.
–Ionosphere - Lower Thermosphere
»Aurora borealis (northern lights)
Energy and the Greenhouse Effect
• Solar Radiation
– Solar energy not evenly distributed over the globe.
– Of solar energy reaching outer atmosphere:
• 25% reflected
• 25% absorbed
• 50% reaches earth’s surface
Solar Radiation
• Visible light passes through atmosphere
undiminished.
• Ultraviolet light is absorbed by ozone in the
stratosphere.
• Infrared radiation is absorbed by carbon dioxide
and water in the troposphere.
Greenhouse Effect
»Increasing atmospheric CO2 due to
human activities appears to be causing
global warming.
El Nino Southern Oscillation
• Large pool of warm surface water in Pacific
Ocean moves back and forth between Indonesia
and South America.
– Most years, the pool is held in western Pacific by
steady equatorial trade winds.
• Every three-five years the Indonesian low collapses and the
mass of warm surface water surges back east.
El Nino Southern Oscillation
– During an El Nino year, the northern jet stream pulls
moist air from the Pacific over the U.S.
• Intense storms and heavy rains.
– During intervening La Nina years, hot, dry
weather is often present.
Greenhouse Gases
• Carbon Dioxide - Fossil-fuel burning.
• Atmospheric levels increasing steadily.
• Methane - Ruminants, Coal-mines
• Absorbs more infrared than CO2.
• Chlorofluorocarbons (CFC’s) - Refrigerants
• Declined in recent years
• Nitrous Oxide - Burning organic material
• Sulfur Hexafluoride - Electrical insulation
Controlling Greenhouse Emissions
• Switch to renewable energy sources.
• Capture and Store CO2.
– Trees and farmland
– Inject into underground strata or deep ocean.
Conventional Pollutants
• US Clean Air Act designated seven major
pollutants for which maximum ambient air levels
are mandated.
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Sulfur Dioxide
Carbon Monoxide
Particulates
Hydrocarbons
Nitrogen Oxides
Photochemical Oxidants
Lead
Indoor Air Pollution
• EPA found indoor concentrations of toxic air
pollutants are often higher than outdoor.
– People generally spend more time indoors.
– Smoking is the most important air pollutant in the US.
• 430,000 die annually from a disease related to smoking.
– Associated costs are estimated at $100 billion annually.
CLIMATE PROCESSES AND AIR
POLLUTION
• Long-Range Transport
– Fine aerosols can be carried great distances by the
wind.
• Sensitive monitoring equipment increasingly reveals
industrial contaminants in places usually considered the
cleanest in the world.
– Contaminants trapped by winds at the north pole,
concentrate and eventually precipitate out, entering the
food chain.
Stratospheric Ozone
• Discovered stratospheric ozone levels were
dropping rapidly during September and October.
– Occurring since at least 1960.
• At ground-level, ozone is a pollutant, but in the
stratosphere it screens UV radiation.
– A 1% decrease in ozone results in a 2% increase in
UV rays reaching the earth.
EFFECTS OF AIR POLLUTION
• Human Health
– EPA estimates each year 50,000 people die
prematurely from illnesses related to air pollution.
• Likelihood of suffering ill health is related to intensity and
duration of exposure.
– Inhalation is the most common route, but absorption
through the skin and consumption via food can also
occur.
CLEAN AIR LEGISLATION
• Clean Air Act (1963) - First national air pollution
control.
• Clean Air Act (1970) rewrote original Act.
– Identified critical pollutants.
– Established ambient air quality standards.
• Primary Standards - Human health
• Secondary Standards - Materials, environment, aesthetic
and comfort.
Clean Air Act
• Revision (1990) - Included provision for:
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Acid Rain
Urban Smog
Toxic Air Pollutants
Ozone Protection
Marketing Pollution Rights
Fugitive emissions of volatile organics
Ambient ozone, soot, and dust.
NOx emissions
Water: Resources and Pollution
Chapter 10
Outline
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Hydrologic Cycle
Water Compartments
Water Availability
Freshwater Shortages
– Increasing Water Supplies
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Water Management and Conservation
Water Pollution
Water Quality Today
Water Pollution Control
Water Legislation
Water Use
• Withdrawal - Total amount of water taken from a
source.
• Consumption - Fraction of withdrawn water made
unavailable for other purposes (Not returned to its
source).
– Degradation - Change in water quality due to
contamination making it is unsuitable for desired use.
Quantities of Water Used
• Water use has been increasing twice as fast as
population growth over past century.
– Worldwide, agriculture claims about 70% of total
water withdrawal.
• In many developing countries, agricultural water use is
extremely inefficient and highly consumptive.
– Worldwide, industry accounts for about 25% of all
water use.
• Cooling water for power plants is single largest industrial
use.
FRESHWATER SHORTAGES
• Estimated 1.1 billion people lack access to an
adequate supply of drinking water.
– 2.4 billion lack acceptable sanitation.
• A country where consumption exceeds more than
20% of available, renewable supply is considered
vulnerable to water stress.
– Globally, water supplies are abundant, but, along with
capital resources, are unevenly distributed.
INCREASING WATER SUPPLIES
• Seeding Clouds
– Condensation Nuclei
• Towing Icebergs
– Cost
• Desalination
– Most common methods are distillation and reverse
osmosis.
• Three to four times more expensive than most other
sources.
Dams, Reservoirs, and Canals
– Displacement of People
• Three Gorges Dams in China will force relocation of over a
million people.
– Evaporation, Leakage, Siltation
• Evaporative losses from Lake Mead and Lake Powell on the
Colorado River is about 1km3 per year (264 billion gallons).
• Dams slow water flow, allowing silt (nutrients) to drop out.
– Loss of Free-Flowing Rivers
Domestic Conservation
• Estimates suggest many societies could save as
much as half of current domestic water usage
without great sacrifice or serious change in
lifestyle.
– Largest domestic use is toilet flushing.
• Small volume of waste in large volume of
water.
• Significant amounts of water can be
reclaimed and recycled.
–Purified sewage effluent
Environmental Geology and Earth Resources
Chapter 11
Outline
• Tectonic Processes
• Minerals and Rocks
• Economic Geology and Mineralogy
– Strategic Resources
• Environmental Effects of Resource Extraction
– Mining
• Restoration
• Conserving Geologic Resources
• Geologic Hazards
Strategic Metals and Minerals
• Of the 80 industrial metals and minerals, between
one-third and one-half are considered strategic
resources.
– A country uses, but cannot produce.
• Considered capable of crippling national
economy or military strength if supplies
were cut off.
–Many less-developed nations depend on
steady mineral exports for foreign
exchange.
CONSERVING GEOLOGIC RESOURCES
• Recycling
– Aluminum must be extracted from bauxite by
electrolysis.
• Recycling waste aluminum consumes one-twentieth the
energy of extraction from raw ore.
– Nearly two-thirds of all aluminum beverage cans in US are
recycled.
– Other metals commonly recycled:
• Platinum, gold, copper, lead, iron, steel.
Solid and Hazardous Waste
Chapter 13
Outline:
• Solid Waste
• Waste Disposal Methods
• Shrinking the Waste Stream
– Recycling
• Hazardous and Toxic Wastes
– Federal Legislation
• RCRA
• CERCLA
– Management Options
WASTE
• According to EPA, US produces 11 billion tons of
solid waste annually.
– About half is agricultural waste.
– More than one-third is mining related.
– Industrial Waste - 400 million metric tons.
• Hazardous/Toxic - 60 million metric tons.
– Municipal Waste - 200 million metric tons.
• Two kg per person / per day.
Waste Disposal Methods
• Exporting Waste
– Although most industrialized nations have agreed to
stop shipping hazardous and toxic waste to lessdeveloped countries, the practice still continues.
• Garbage imperialism also operates in wealthier countries.
• Indian reservations increasingly being approached to store
wastes on reservations.
Recycling
• Potential Problems
– Market prices fluctuate wildly.
– Contamination
• Most of 24 billion plastic soft drink bottles sold annually in
the US are PET, which can be melted and remanufactured
into many items.
– But a single PVC bottle can ruin an entire truckload of
PET if melted together.
HAZARDOUS AND TOXIC WASTES
• EPA estimates US industries generate 265 million
metric tons of officially classified hazardous
wastes annually.
– At least 40 million metric tons of toxic and hazardous
wastes are released into the environment each year.
Hazardous Waste Disposal
• Federal Legislation
– Resource Conservation and Recovery Act (RCRA) 1976.
• Comprehensive program requiring rigorous testing and
management of toxic and hazardous substances.
– Cradle to grave accounting.
Superfund Sites
• EPA estimates 36,000 seriously contaminated sites
in the US.
– By 2000, 1,551 sites had been placed on the National
Priority List for cleanup with with Superfund financing.
• Superfund is a revolving pool designed to:
– Provide immediate response to emergency situations
posing imminent hazards.
– Clean-up abandoned or inactive sites.
Superfund Sites
• Total costs for hazardous waste cleanup in the US
are estimated between $370 billion and $1.7
trillion.
– For years, most of the funding has gone to legal fees,
but this situation has improved over past several years.
• Studies of Superfund sites reveal minorities tend to
be over-represented in these neighborhoods.
Sustainability and Human Development
Chapter 14
Outline
• Sustainability and Resources
– Classical Economics
– Neo-Classical Economics
– Ecological Economics
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Resource Accounting
Trade and Development
Urban Development
Urban Problems in Developing Countries
Smart Growth
SUSTAINABILITY AND RESOURCES
• Sustainability is a critical theme of environmental
science.
– Resources should be used in ways that do not
diminish them.
• Sustainable Development
– Meeting the needs of the present without
compromising the ability of future generations to
meet their own needs.
• Must be available to all to be enduring.
– Goal to decrease uneven distribution of resources.
Economics and Sustainable Development
Sustainable growth is a contradiction –
can’t keep growing indefinitely
Sustainable use applies only to renewable
resources – use them at rates within their
capacity for renewal
Ecological Economics
• Developed in recent decades, and applies
ecological ideas of system functions and recycling
to the definition of resources.
• Acknowledges dependence on essential lifesupport services provided by nature.
• Regards some aspects of nature as irreplaceable
and essential.
• Principle concern is fair and even distribution of
resources and rights.
Good luck!