Environmental Problems,
Their Causes, and
Sustainability
Chapter 1
WHAT IS ENVIRONMENTAL
SCIENCE?
Environmental science is a
study of connections in nature
• Environment…
• Science…
• Ecology…
• Environmentalism…
WHAT ARE THREE PRINCIPLES
OF SUSTAINABILITY?
Three principles of sustainability
Sustainability has certain key
components
• Life depends on natural capital, natural
resources and natural services.
Key natural resources and
services
Nutrient cycling
Some resources are renewable
and some are not
• A perpetual resource is continuously renewed
and expected to last (e.g. ?).
• A renewable resource is replenished in days to
several hundred years through natural processes
(e.g. ?).
• Sustainable yield is the highest rate at which a
renewable and non-renewable resource can be
used indefinitely without reducing its available
supply (e.g. ?).
Some resources are renewable
and some are not
• Some resources are not renewable.
– Nonrenewable resources exist in fixed
quantities.
– Exhaustible energy (e.g.
– Metallic minerals (e.g.
– Nonmetallic minerals (e.g.
• Sustainable solutions: 3 R’s
(Jack Johnson)
http://www.youtube.com/watch?v=ShC0RqSANr4
80-90% metal & plastic
recycling Know-how
).
).
).
Rich and poor countries have
different environmental impacts
• Developed countries include the high
income ones
– e.g.
• Developing countries include the low
income ones
– e.g.
Section 1-2
HOW ARE OUR ECOLOGICAL
FOOTPRINTS AFFECTING THE
EARTH?
We are living unsustainably
• Environmental, or natural capital,
degradation is occurring.
• Examples?
• We have solutions to these problems that
can be implemented.
• Examples?
Degradation of normally
renewable natural resources
Pollution comes from a number
of sources
• Point sources are single, identifiable
sources (e.g.,
).
• Nonpoint sources are dispersed and
often difficult to identify (e.g.,
What can we do?
).
Pollution comes from a number
of sources
• Clean it up…
Or
• Prevent it…
• Which is “better”?
Why?
The tragedy of the commons: overexploiting
shared renewable resources
• In 1968, the biologist Garrett Hardin called
the degradation of openly shared
resources the tragedy of the commons.
• Reducing degradation.
– Reduce use by government regulations.
– Shift to private ownership.
Ecological footprints: our
environmental impacts
• Ecological footprint is the amount of
biologically productive land and water
needed to supply a person or country with
renewable resources and to recycle the
waste and pollution produced by such
resource use.
• Per capita ecological footprint is the
average ecological footprint of an
individual in a given country or area (per
person).
Ecological footprints: our
environmental impacts
• Ecological deficit means the ecological
footprint is larger than the biological
capacity to replenish resources and
absorb wastes and pollution.
• Humanity is living unsustainably.
By what %???
30% World
~90% U.S.
• Footprints can also be expressed as
number of Earths it would take to support
consumption.
Total and per capita ecological
footprint of selected countries
IPAT is another environmental
impact model
• In the early 1970s, scientists Paul Ehrlich
and John Holdren developed the IPAT
model.
• I (environmental impact) =
P (population size) x
A (affluence/person) x
T (technology’s beneficial and harmful effects).
I=PxAxT
Section 1-3
WHY DO WE HAVE
ENVIRONMENTAL PROBLEMS?
Causes of Environmental Problems
Population
growth
Unsustainable
resource use
Poverty
Excluding
environmental costs
from market prices
Fig. 1-10, p. 16
Exponential growth
Poverty has harmful environmental
and health effects
• Poverty occurs when…
• One in every five people live in extreme
poverty (<$1.25/day), and more are
susceptible.
Harmful effects of poverty
Malnutrition
Prices of goods and services due not include
harmful environmental and health costs
• A company’s goal is often to maximize the profit.
• Often consumers do not know the damage
caused by their consumption.
• Government subsidies may increase
environmental degradation.
• There are ways to include harmful costs of
goods and services.
– Shift from environmentally harmful to beneficial
government subsidies.
– Tax pollution and waste heavily while reducing taxes
on income and wealth.
People have different views about
environmental problems and their solutions
• Each individual has their own environmental
worldview—a set of assumptions and values
reflecting how you think the world works and
what your role should be.
• Environmental ethics
• Planetary management worldview
People have different views about
environmental problems and their solutions
•
•
•
•
•
•
Environmental ethics
Why should be care about the environment?
Are we the most important species?
Is it a sin to cause extinction?
Do we owe future generations anything?
Do we all have inalienable environmental
rights?
People have different views about
environmental problems and their solutions
• Each individual has their own environmental
worldview—a set of assumptions and values
reflecting how you think the world works and
what your role should be.
• Environmental ethics
• Planetary management worldview
People have different views about
environmental problems and their solutions
• Stewardship worldview
• Environmental wisdom worldview
Section 1-4
WHAT IS AN ENVIRONMENTALLY
SUSTAINABLE SOCIETY?
What is an environmentally
sustainable society?
• Environmentally sustainable societies protect
natural capital and live off its income.
– Increase reliance on renewable resources.
– Protect earth’s natural capital.
• We can work together to solve environmental
problems.
– Trade-off solutions provide a balance between
the benefits and the costs.
– Individuals matter especially in success of
bottom-up grassroots action.
Three Big Ideas
1. Solar Power!!!
2. Protect Biodiversity
3. Help sustain earth’s natural chemical cycles