Transcript Chapter 1 Environmental Problems, Their Causes and

Chapter 1
Environmental Problems, Their Causes
and Sustainability
AP Environmental Science
ENHS
Discussion Questions
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What are the major themes of the book?
What keeps us alive? What is an environmentally sustainable
society?
How fast is the human population growing?
What is the difference between economic growth, economic
development, and environmentally sustainable economic
development?
What are the earth’s main type of resources? How can they be
depleted or degraded?
What are the principal types of pollution, and what can we do
about pollution?
What are the basic causes of today’s environmental problems,
and how are these causes connected?
• What are the harmful effects of poverty and affluence?
• What three major cultural changes have take place since
humans arrived?
• What are the fours scientific principles of sustainability and how
can they help us build more environmentally sustainable and
just societies?
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Core Case Study - Living in a Sustainable
Age: Life in the Fast Lane
• Chess between kings
• Exponential growth – a
quantity increases at a
fixed percentage per
unit of time.
– Starts slow but…… (Fig.
1-1)
• 10000 YA – 5 million
people
• present – 6.6 billion
humans
• 2100 – 8-10 billion
• Human activities cause major changes to
earth’s systems.
– Mass extinctions (0.1-1% per year) – forests,
grasslands, wetlands, coral reefs, and topsoil
vanish or degrade.
• Human ecological footprint spreads exponentially across
the globe.
– Climate change is also due to exponential growth
of human activities
• Can negatively effect:
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Water supply
Agriculture
Biodiversity
Economies
Living More Sustainably
• What is environmental science (ES)?
– Studies how earth works, how we interact w/ the
earth, and how to deal w/ environmental
problems.
• Environment – sum of all living and nonliving
things that affect organisms.
– Living things can also influence the environment.
• Exponential increase in human population is
accompanied by an exponential increase in consumption
 degradation/depletion of air, water, soil, and
biodiversity.
• Continuation of this trend can threaten long-term
sustainability of our societies.
• ES is interdisciplinary
study integrating (Fig.
1.2)
– Natural sciences (Bio,
Chem, Geol)
– Social Science
(Economics, Politics,
Ethics)
• Goal of ES
– Learn how natural
systems works
– How environment affects
us
– How we affect the
environment
– How we can live
sustainably w/o
degrading our lifesupport system.
• Basic tool of ES, ecology – study of the relationships
between organisms and their environment.
• Environmentalism (not the same as ES or Ecology)
– Social movement for protecting earth’s life-support system
for us and other species.
– Political in nature
• Pass and enforce laws
• Promote solutions to environmental problems
• Protest harmful environmental actions
Sustainability: The Integrative Theme
of This Book
• Fig 1-3
• Sustainability – ability of earth’s systems (including
human cultural systems and economies) to survive
and adapt to changing environmental conditions
indefinitely.
– Natural capital
– Natural capital degradation
• Use of normally renewable resources faster than nature can
renew them.
– Solutions
– Individuals matter (Fig. 1.4)
• Sound science – concepts and ideas that are widely
accepted by experts in fields of natural and social
sciences.
Environmentally Sustainable Societies:
Protecting Natural Capital and Living off its
Income.
• Meets current and future needs of its people
for basic resources in a just and equitable
manner w/o compromising the ability of
future generations to meet their needs.
• Living sustainably – living off natural income
replenished by soils, plants, air and water and
not depleting or degrading the earth’s natural
capital that supplies this income.
• Economic Capital
– 10 % annual interest and one million dollars
– Spend $100 000 a year – sustainable
– Spend $200 000 a year – gone in 7th year
– Spend $110 000 a year – gone in 18th year
– Lesson, protect capital and live on income
• Same lesson should be applied to earth’s
natural capital.
Population Growth, Economic Growth,
and Economic Development
• Human Population Growth: Slowing but Still Rapid
– Population increasing exponentially, faster in poor countries.
– As of 2006, increasing by 1.23 %
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81 million in 2006
or, 222 000 day-1
9250 h-1
2.6 sec-1
– Exponential increase in population is accompanied by an
exponential increase in use of natural resources.
• Less time to find solutions to environmental problems.
• Economic Growth and Economic Development
– Economic growth – increase in goods and services.
• Requires more producers and consumers (i.e., population
growth);
• and/or, more production and consumption per person.
– Gross domestic product (GDP) – annual market value of all
goods and services produced by all firms and organizations,
foreign and domestic, operating w/in a country.
• Growth, measured by percent change in GDP.
– per capita GDP – GDP divided by the total population at
midyear.
• Six largest economies in 2006 – US, Japan, Germany, UK,
France, and China.
– Economic development – improvement of human living
standards by economic growth.
• Classification depends on degree of industrialization and per
capita GDP-PPP.
• Developed countries – 1.2 billion. US, Canada, Japan,
Australia, New Zealand, and most of Europe.
• Developing countries – 5.4 billion. African, Asian, and Latin
American
– Moderately developed countries – China, India, Brazil, and Mex.
– About 97% of projected population increase will be from
developing countries (Figs. 1.5 and 1.6).
– Environmentally sustainable economic development
• Doubling Time and Exponential Growth: The
Rule of 70.
– Doubling time can be calculated with the
following:
tdouble
70

%GR
Resources
• What is a resource?
– Anything obtained from the environment to meet
our needs (and wants).
• Food, water, shelter, and metals
– Some directly available, others indirectly
• Directly – sun, fresh air, wind, fresh surface water, fertile
soil, and wild edible plants.
• Indirectly – petroleum, ground water, iron, and modern
crops.
– Such resources require human capital (and ingenuity) and
natural capital.
• Perpetual and Renewable Resources
– Perpetual resources – continuously renewable on a human
timescale
– Renewable resource – can be replenished fairly rapidly as
long as it is not used faster than it can be replaced.
• Forests, grasslands, wildlife, fresh air and water, and fertile soil
– Sustainable yield – highest rate a renewable resource can be
used without degrading or depleting.
– Environmental degradation – when natural replacement rate
is exceeded.
• Urban sprawl, topsoil erosion, pollution, clearing forests,
depleting groundwater, reduction of biodiversity because of
habitat loss.
• Tragedy of the Commons
– Overuse of common-property (or free access resources).
• Clean air, open ocean, migratory birds, freshwater
– Degradation of renewable free access resources, called
tragedy of the commons by biologist Garrett Hardin.
• Example: collapse of fisheries.
– Solutions to preventing such degradation.
• Use free access renewable resources at rates below sustainable
yields.
• Convert free-access resources to private ownership.
• Ecological Footprint – the amount of biologically
productive land and water needed to supply an area
with resources and to absorb the wastes and
pollution produced from such resource use.
– per capita ecological footprint (Fig. 1.7).
– Humanity’s ecological footprint is estimated to be 39%
above earth’s ecological capacity.
• US, EU, China, India and Japan together use 74% of earth’s
ecological capacity.
• The US outdoes every other country by at least two-fold.
• If China and India were to catch up to present US
consumption, they would need two require two planet earths.
– Three factors that have the greatest ecological footprint:
agriculture, transportation, and heating and cooling
buildings.
• Nonrenewable Resources
– Includes energy resources, metallic mineral
resources, and nonmetallic mineral resources.
– Fossil fuels would be exhausted as there is
exponential growth in their use.
– Recycling and reusing metals and non-metallic
minerals
Pollution
• Sources of Harmful Effects of Pollutants
– Pollution – the presence of chemicals a t high enough levels
in air, water, soil, or food to threaten the health, survival, or
activities of humans or other living organisms.
• Point sources (Fig. 1.9)
• Non-point sources
– Three types of unwanted effects:
• Disrupt or degrade life-support systems
• Damage wildlife, human health, and property
• Create nuisances, noise and unpleasant smells, tastes, and
sights.
• Solutions: Prevention versus Cleanup
– Pollution prevention (input pollution control)
– Pollution cleanup (output pollution control)
• Problems with relying on cleanup
– Temporary bandage
– Removes pollutants from one part of the environment
causing pollution elsewhere.
– Once pollutants are at harmful level, too expensive or
impossible to reduce them to acceptable levels.
Environmental Problems: Causes and
Connections
• Key Environmental Problems and Their Basic
Causes
– Problems are mostly the result of exponential
population growth and resource use (Fig. 1.10).
– Underlying causes (Fig. 1.11)
• Three other likely causes:
– Global trade policies that undermine environmental
protection.
– Influence of money and politics.
– Failure to provide inspiring and positive visions of a more
sustainable and durable economic future.
• Poverty – is the inability to meet one’s basic
economic needs and is concentrated mostly in the
southern hemisphere.
– Many desperate for basic needs (Fig. 1.12)
– Deplete or degrade forests, soil, grasslands, and wildlife for
short-term survival
• Don’t have luxury of worrying about long-term environmental
quality
• Poor people often have many children as a form of
economic security
• 7 million die prematurely each year
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Malnutrition
Depressed immunity
Lack of clean drinking water
Respiratory disease from inhaling indoor pollutants
• Beneficial Effects of Affluence on Environmental
Quality
– Money for developing cleaner and more efficient
technologies.
– Affluence financed improvements in the US since the 1970s
– Downside
• Clean up by transferring wastes and pollution to more distant
locations
• Obtain resources from anywhere in the world w/o seeing
harmful environmental impacts of high-consumption life styles.
• Resource Consumption and Environmental Problems
– Prosperous over-consume
– Affluenza – term coined to describe the unsustainable
addiction to over-consumption and materialism exhibited in
the lifestyles of many affluent consumers in the US and
other developed countries and the rising middle class in
China and India.
• Has enormous environmental impact
• Large amounts of pollution, environmental degradation, and
wastes.
– Expert on the growth and decline of civilizations Arnold
Toynbee
• True measure of growth – law of progressive simplification –
shift from material to nonmaterial developing culture,
compassion, sense of community, and strength of democracy.
• Connections between Environmental
Problems and Their Causes
– Three factor model (Fig. 1-14)
• Impact = Population x Affluence x Technologies
• In US, per capita resource use is up to 100 times greater
than the world’s poorest countries.
• Some technologies are environmentally harmful, others
beneficial.
Cultural Changes and the environment
• Human Cultural Changes
– Homo sapiens sapiens – 90 to 195 thousand y.a.
• Agricultural revolution – 12 000 y.a.
• Industrial-medical revolution – 275 y.a. (Fig. 1.15)
• Information-globalization revolution – 50 y.a.
– Living conditions are better, but progress has put a strain
on earth’s natural capital.
• Eras of Environmental History in the US
– Tribal era, at least 10 000 years before European
settelers
– Frontier era, 1607-1890
– Early conservation era, 1832-1870
– Modern environmental era, 1870 to present –
government and private citizens in resource
conservation, public health, and environmental
protection.
Sustainability and Environmental
Worldviews
• Are Things Getting Better or Worse? A
Millennium Assessment
– Two schools of thought:
• Technological advances will allow us to keep growing.
• Global economy is outgrowing the capacity for earth to
support it.
– The 2005 UN’s Millennium Ecosystem Assessment
• 1360 experts from 95 countries
• Human activity degrading or using unsustainably about
60 % of world’s free natural services.
• Report also says we have the tools to preserve earth’s
natural capital.
• Challenge: not to get trapped into confusion and inaction
by listening primarily to either two:
– Technological optimists
– Environmental pessimists
– Sustaining our current global civilization depends
on:
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Shifting to a renewable energy-base;
a reuse/recycle economy;
and a diversified transport system.
Making the transition requires:
– restructuring a global economy to sustain civilization;
– an all-out effort to eradicate poverty, stabilize population,
and restore hope; and
– a systematic effort to restore natural systems.
• Environmental Worldviews and Ethics
– Differing views on the state of the environment depends on
environmental worldview and environmental ethics.
– Environmental worldview – set of assumptions and values
about how you think the world works and what you think
your role in the world should be.
• Planetary management worldview – separate from the natural
world
• Stewardship worldview – manage earth for our benefit,
stewardship
• Environmental wisdom worldview – part of and totally
dependent on nature; nature exists for all species.
– Environmental ethics – beliefs about what is right and wrong
w/ how we treat the environment.
• Four Scientific Principles: Copy Nature
– Four basic components of the earth: natural sustainability
• Reliance on solar energy
• Biodiversity – genes, species, ecosystems, and ecological
processes
• Population control
• Nutrient recycling (Fig. 1-16)
– Fig. 1-17
– The four scientific principles of sustainability as a guide
could lead to an environmental revolution (Fig. 1-18).
• Building Social Capital: Talking and Listening to One
Another
– Social capital – positive force created when people w/
different views and values find common ground and work
together to build understanding, trust and informed shared
visions of what their communities, states, nations, and world
could and should be.
– Stakeholders of all sides have some legitimate and useful
insights.
• Social capital can be built by finding trade-off solutions.
• Individuals matter – 5 to 10% of population can bring major
social change.
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SOLAR
CAPITAL
EARTH
Goods and services
Heat
Human Capital
Natural Capital
Human
Economic
and
Cultural
Systems
Depletion of
nonrenewable
resources
Degradation of
renewable resources
Pollution and waste
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