Transcript environmental science: a global perspective

ENVIRONMENTAL SCIENCE:
A GLOBAL PERSPECTIVE
What Is Environmental Science?
Environmental Science is the study of how the earth
works, how we interact with and affect the
environment, and how to deal with environmental
problems.
What Is Meant By The
“Environment”?
• It is everything around us.
• It is the natural world as well as things
produced by humans.
What Are Our Main
Environmental Problems?
1. RESOURCE DEPLETION
– A resource is any natural substance used by living
things such as sunlight, air, water, soil…
-Nonrenewable resources- resources that cannot
be replaced such as copper, uranium, and even
trees if they are cut down faster than new ones can
form.
-Renewable resources – resources that are
continually being replaced such as sunlight, trees
and fish.
2. POLLUTION
The introduction of harmful levels of
chemicals or waste material into the
environment.
Many pollutants are byproducts of burning fossil
fuels (which gets into our air) and by agriculture
(which gets into our waters).
Pollutants can harm plants, animals and humans.
3. EXTINCTION
- Is when the last individual member of a
species and died and the species is gone
forever.
- Species today are disappearing faster
than ever before.
- Some organisms that are now extinct are
the passenger pigeon, dodo bird, Baiji white
dolphin and the bigleaf scurfpea.
Many Environmental Problems Are
Global Problems
• Ex: sulfur dioxide released by coal plants in the
American Midwest fall back to Earth as acid rain
in Canada.
• Ex: Cars driven in America and Europe increase
the amount of carbon dioxide (CO2) which may
cause the climate of the entire Earth to change.
• Ex: deforestation in South America contributes
to the increase in carbon dioxide (CO2)
• Biosphere- bio= living
• It is the thin layer of life around the
earth.
• It extends about 5 miles above earth
and 5 miles below the surface.
Most Of The Nations Can Be Placed In
One Of Two Groups
• Developed Countries
• 1.2 billion people
• Us, Canada, Japan,
Australia, New Zealand,
most European
countries
• Citizens have higher
incomes
• More industrialized
• Developing Countries
• 5.4 billion people
• Most in Africa, Asia and
Latin America
• China, India, Brazil,
Mexico
• Citizens have lower
incomes
• Less industrialized
Increasing Population Can Create
Environmental Problems
• More people = more demand for resources
• Is most severe in the developing nations
• People struggle just to survive and may strip
forests and kill endangered animals.
Consumption Of Resources Can Create
Environmental Problems
• The consumption crisis is most severe in
developed nations
• Developed nations use 75% of the resources
used every year and make up 20% of the
world’s population.
What Does It Mean To Be Sustainable?
• A state in which humans can exist indefinitely
with a high standard of living and health
while preserving habitats and resources.
• This is the goal of environmental problem
solving.
Let’s Not Forget The
Scientific Method!
• Used to find answers to questions about the
world around us.
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1. Observe
2. Form a question
3. Hypothesize
4. Test the hypothesis (experiment)
5. Organize and interpret data with tables,
graphs, and charts
• 6. Communicate results
Scientific Method Specifics
• Good observations include accurate and
detailed descriptions
• A hypothesis is a testable explanation for an
observation
• In an experiment, 2 groups or situations are
studied. There can be only 1 difference
(independent variable) between the 2 groups
• All data must be carefully and accurately
recorded in order to determine if the
hypothesis was supported
• All tables/graphs must be labeled and titled
correctly to enable scientists to convey
comparisons and trends they have discovered.
• Communicating results must be done in such as
way as to include the entire experiment- the
hypothesis, relevant background information,
exact description of the work done, the data
collected and the evaluation of the data. The
experiment must be able to be repeated by
others who get the same results as well.
Why Do We Have Environmental
Problems?
• People with different environmental
worldviews often disagree about the
seriousness of environmental problems and
what we should do about them.
Different Views About Environmental
Problems And Their Solutions
– Planetary management worldview – nature
exists for our use and benefit. We are separate
from nature.
– Stewardship worldview –we use nature for our
benefit, but we must make wise decisions
concerning the sustainability of the planet
– Environmental wisdom worldview - we are a
part of nature and no more important than any
other part. We must learn to integrate into the
Earth systems.
Values That Affect
Environmental Decision Making
Aesthetic- what is beautiful or pleasing
Economic
Environmental
Educational
Ethical/moral
Health
Recreations
Scientific
Social/cultural
Footprints
• What is an ecological footprint?
• Is the world’s footprint growing or shrinking?
• What happens to the resources as the
footprint changes?
What Is An Ecological Footprint?
• Amount of productive land and water needed
to supply the people in an area with
resources to live and the community’s ability
to absorb and recycle the wastes and
pollution they produce by using resources.
• Per capita ecological footprint - the average
ecological footprint of an individual in a given
area.
How Is The Planet’s Ecological Footprint?
• In 2003, the World Wildlife Fund and Global
Footprint Network estimated that the global
ecological footprint exceeded the earth’s
biological capacity by about 25% but it was
88% in the world’s high-income countries.
• American’s are the second largest consumers
of resources, and if everyone used resources
the way we do, the Earth could only support
1.3 billion people.
Calculating Your Ecological Footprint
• If everyone on earth lived your lifestyle, how
many earths would be needed to support all
the people?
• Web activity- calculate your footprint
Common Resources- Think About It!
• What are some common resources that must
be shared?
• Are resources distributed equally around the
world?
• Are resources shared equally?
• Do resource-rich countries
have an obligation to share
with resource-poor countries?
Overexploiting Shared Renewable
Resources: Tragedy of the Commons
• Three types of property or resource rights
– Private property
– Common property (1/3 of all land in US is owned
by the people and managed by the government)
– Open access renewable resources- use is regulated
by government (open oceans /fish and clean air)
Garrett Hardin and the
Tragedy of the Commons
 Overuse of common property resources, which are
owned by no one but available to everyone free of
charge.
 Examples are clean air, oceans, fish, Antarctica.
 This leads to exploitation and then no one can use the
resource.
 “ If I don’t use this resource then someone else will, the
little bit I pollute is not enough to matter”
What’s the use of a house if you don’t have
a decent planet to put it on?
-HENRY DAVID THOREAU
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What’s the use of a house if you don’t have a decent planet to
put it on?
-HENRY DAVID THOREAU