Download Principles of Environmental SCIENCE

Chapter 1
Understanding
our
Environment
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Today we are faced with a challenge that
calls for a shift in our thinking,
so that humanity stops threatening its
life-support system.
–Wangari Maathai, winner of 2004 Nobel
Peace Prize
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Case Study:
Saving the Reefs of Apo Island
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1.1 Understanding Our
Environment
• In this course you will
learn about many
serious environmental
problems like
overfishing.
• You will also read
about promising,
exciting solutions to
many of these
problems.
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We Live on a Marvelous Planet
• The conditions on Earth
are unique.
• Plentiful supplies of
clean air, fresh water,
and fertile soil are
constantly regenerated
by biological
communities.
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Our Planet Has an Amazingly
Rich Diversity of Life
• Millions of species
populate the earth and
help sustain a
habitable environment.
• They create complex,
interrelated
communities and selfsustaining
ecosystems.
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What is Environmental Science?
• Environmental
science is the
systematic study of
our environment and
our place in it.
• It is multidisciplinary.
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1.2 Problems and Opportunities
• Approximately 7 billion people
on Earth, we are adding about
80 million more each year.
• Present trends project a world
population between 8 and 10
billion by 2050.
• The impact of that many
people on our natural
resources and ecological
systems complicates many of
the other problems we face.
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Environmental Problems:
Climate Change
• Human activities (burning
fossil fues, clearing forests
and farmlands, raising
ruminant animals) have
greatly increased
concentrations of carbon
dioxide and other
―greenhouse‖ gases over
the last 200 years.
• Climate models indicate
that by 2100, if current
trends continue, global
mean temperatures will
probably warm between
about 2 and 6 ˚ C.
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Environmental Problems:
Food Supply
• Over the past century,
global food production
has increased faster than
human population
growth, but hunger
remains a chronic
problem.
• At least 60 million people
face acute food
shortages due to
weather, politics, or war.
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Environmental Problems:
Clean Water
• 1.1 billion people lack
access to safe drinking
water.
• Every year polluted
water contributes to the
death of more than 15
million people.
• 40% of the population
live in countries where
water demands now
exceed supplies.
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Environmental Problems:
Energy Resources
• Fossil fuels (oil, coal, and natural gas) presently provide
around 80 percent of the energy used in industrialized
countries.
• Supplies of these fuels are diminishing, and there are
many problems associated with their acquisition and use.
• Investing in renewable energy and energy conservation
measures could give us cleaner, less destructive options.
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Forest damaged by acid rain. By Getty Images on The Discovery Channel.
Environmental Problems:
Air Quality
• Air quality has worsened dramatically in
many areas, especially in southern Asia.
• Nobel laureate Paul Crutzen estimates that
at least 3 million people die each year from
diseases triggered by air pollution.
• Worldwide, 2 billion metric tons of air
pollutants (not including carbon dioxide or
wind-blown soil) are released each year.
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Environmental Problems:
Biodiversity loss
• Habitat destruction,
overexploitation,
pollution, and
introduction of exotic
organisms are
eliminating species at a
rate comparable to the
great extinction that
marked the end of the
age of dinosaurs.
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Environmental Problems:
Marine Resources
• More than a billion people
depend on seafood for their
main source of animal protein.
• According to the World
Resources Institute, more than
three-quarters of the 441 fish
stocks for which information is
available are severely depleted
or in urgent need of better
management.
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Signs of Hope:
Population and Pollution
• Population is stabilizing.
• Over the past 25 years, the average number
of children born per woman worldwide has
decreased from 6.1 to 2.6
• The UN Population Division predicts that the
world population will stabilize at about 8.9
billion by the year 2050.
• Pollution has been
decreasing in most
industrialized countries.
Image from: http://www.miller-mccune.com/science-environment/core-of-the-problem-4036/
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Signs of Hope: Health
• The incidence of
life-threatening
infectious diseases
like smallpox and
polio have been
reduced sharply in
most countries
during the past
century, while life
expectancies have
nearly doubled.
Global Health in 4 minutes.
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Signs of Hope: Renewable Energy
• Renewable energy: Encouraging progress
is being made in a transition to renewable
energy sources.
– The European Union and China are developing wind
energy, hydropower, solar, wave and tidal energy, and
improvements in efficiency to cut reliance on fossil
fuels.
– At the Copenhagen climate summit in 2009, the
world's wealthiest countries agreed to aid developing
nations in finding alternative energy technologies.
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Signs of Hope: Conservation of
Forests and Nature Preserves
• Deforestation has
slowed in Asia.
• Brazil, which has led
global deforestation
rates for decades, is
working to protect
forests.
• Nature preserves and
protected areas are on
the increase.
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Signs of Hope:
Protection of Marine Resources
• Protecting fish
nurseries represents
an altogether new
approach to protecting
marine ecosystems.
• Marine reserves are
being established in
California, Hawaii,
New Zealand, and
Great Britain.
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1.3 Human Dimensions of
Environmental Science
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Poverty Causes
Environmental Damage
• The World Bank estimates that more than
1.4 billion people—about one-fifth of the
world’s population—live in acute poverty
with an income of less than $1 (U.S.)/day.
• We must work to break the poverty cycle.
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The Cost of Affluence
―And may we continue to be worthy to consume a
disproportionate share of the planet’s resources.‖
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Affluence also has
Environmental Costs
• The affluent lifestyle that many of us in the
richer countries enjoy consumes an
inordinate share of the world’s natural
resources and produces a shockingly high
proportion of pollutants and wastes.
• The U.S., for instance, with less than 5%
of the total population, consumes about
25% of commodities, such as oil, and
produces 25-50% of the industrial wastes.
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Sustainability is a
Goal
• Sustainability is a search for ecological
stability and human progress that can
last over the long term.
• Sustainable development is ―meeting
the needs of the present without
compromising the ability of future
generations to meet their own needs.‖
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Where do Rich and Poor Live?
• About one-fifth of the world’s population
lives in the 20 richest countries, where the
average per capita income is above
$25,000 (U.S.) per year.
• Eighty percent of the world’s population
lives in middle- or low-income countries,
where nearly everyone is poor by North
American standards.
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Indigenous Peoples are Guardians
of Much of the World’s Biodiversity
• Often, the 500 million
indigenous people
who remain in
traditional homelands
still possess valuable
ecological wisdom
and remain the
guardians of littledisturbed habitats.
• Biopiracy
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Cultural Diversity and Biological
Diversity Often Go Together
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Science is a Cumulative Process
• Good science is rarely carried out by a single
individual working in isolation. Instead, a
community of scientists collaborates in a
cumulative, self-correcting process.
• The idea of consensus is important in science.
• Sometimes new ideas emerge that cause major
shifts in scientific consensus. These great
changes in explanatory frameworks ware called
paradigm shifts.
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Critical Thinking
• An ability to think critically, clearly, and
analytically about a problem may be the most
valuable skill you can learn.
• Critical thinking is a term we use to describe
logical, orderly, analytical assessment of ideas,
evidence, and arguments.
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1.6 Where Do Our Ideas About The
Environment Come From?
• Many of our current views on the environment
are rooted in the writings of relatively recent
environmental thinkers.
• Their work can be grouped into 4 stages:
– Resource conservation for optimal use
– Nature preservation for moral and aesthetic reasons
– Concern over health and ecological consequences of
pollution
– Global environmental citizenship
• These stages are not mutually exclusive.
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Peer Teach Exercise
• Purpose
– Instead of lecture, students teach their peers about
the leading environmental thinkers
• Directions
– I would like each student to pick a name of an
environmental thinker (a list will be provided on
the next slide).
– Strive to become an expert on your individual.
– Share what you have learned with the rest of the
class.
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Peer Teach Exercise
• Create a PowerPoint of the following and make it visually
appealing. Post your work in the Discussion section
called ―Environmental Thinkers‖, and visit other student
submissions to learn more about these important people.
Below are some suggestions to include in your
PowerPoint.
– Name of person and at least one photograph (more is better)
– Year born/died
– Profession
– Stage they are a part of (see text book)
– Focus of their environmental concern (what they cared about)
– Great achievements (could include an activity, a policy they created, a
book they wrote, etc.) Name at least 3.
– Famous quote (at least one)
– Cite all sources and images used (APA style)
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Environmental Thinkers
• Research one of the following and post in the discussion
section. Make sure that in the ―subject‖ area of your post
you list the name of the person you studied. Your book
will get you started but use the internet for more
information.
– President Teddy Roosevelt
– Gifford Pinchot
– John Muir
– Aldo Leopold
– Rachel Carson
– David Brower
– Barry Commoner
– Wangari Maathai
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Conclusion
• Environmental science gives us useful tools and
ideas for understanding both environmental
problems and new solutions to those problems.
• We face many severe and persistent problems,
but we can also see many encouraging
examples of progress.
• Science helps us analyze and resolve these
problems because it provides an orderly,
methodical approach to examining problems.
• Environmental thought has evolved in response
to environmental deterioration.
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