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Chapter 1

Understanding

our

Environment

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

1-2

Case Study:

Saving the Reefs of Apo Island

1-3

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.

1-5

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 self-

sustaining

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. 1-9

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.1-12

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.1-11

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.

1-12

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. 1-15

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.1-16

Image from: http://www.miller-mccune.com/science-environment/core-of-the-problem-4036/

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.

1-17Global Health in 4 minutes.

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.‖1-23

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 little-

disturbed 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.

1-30

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.09/22/10

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)09/22/10

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 Maathai09/22/10

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.1-35