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Scott Brennan • Jay Withgott
Unit 1: We and Our Environment
Fundamental Environmental Issues
Big Question: Why Is Science Necessary to Solve
Environmental Problems?
Dr. Manish Kumar
Dept of Environ. Science
Tools To Study The Environment
• The nature of environmental science
• The scientific method and the scientific process
• Natural resources and their importance
• Culture and worldviews
• Environmental ethics
• Sustainability
The “environment”
Consists of both:
Biotic factors (living things) and
Abiotic factors (nonliving
things) that surround us and with which
we interact.
Definitions: (Ironically not always defined…;-)
Humans and the environment
• We humans exist within the environment and are a part of the natural world.
• Like all other species, we depend for our survival on a properly functioning planet.
• Thus, our interactions with our environment matter a great deal.
Natural resources
• Renewable resources like sunlight cannot be depleted.
• Nonrenewable resources like oil CAN be depleted.
• Resources like timber and clean water are renewable only
if we do not overuse them. Figure 1.1
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Global human population growth
• Our population has skyrocketed to over 6 billion.
• The agricultural and industrial revolutions drove population growth.
Figure 1.2
Thomas Malthus (1766-1834)
Population growth will lead to starvation, war, disease.
Death rates check population unless birth rates are lowered.
In our day, Paul Ehrlich (The Population Bomb, 1968) is called “neo-Malthusian.”
Figure 1.3
Garrett Hardin, 1968:
In a “commons” open
to all, unregulated use
will deplete limited
resources.
Figure 1.4
The tragedy of the commons
If you’re not part
of the solution….
…you’re part
of the
problem.
What should we do about the environment?
Greenhouse effect
Global warming
Pollution
Slash and burn
Animal extinction
Environmental science
How does the natural world work?
How does our environment affect us?
How do we affect our environment?
Applied goal: Developing solutions to environmental problems.
What is an “environmental problem?”
Definitions differ.
The pesticide DDT:
was thought safe in 1945
is known to be toxic today
but is used widely in Africa to combat malaria
Figure 1.5
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A Global Perspective
Today our actions are experienced worldwide.
Life makes Earth’s environment unlike that of other planets.
The Gaia hypothesis proposes that the global environment has been profoundly changed by life throughout the history of life on Earth, and that these changes have improved the chances that life on Earth will continue.
See the Wikipedia article: Think Globally, Act Locally.
Cities Affect the Environment
We are becoming an urban species, and our effects on the environment are more and more the effects of urban life.
We must look more closely at the effects of urbanization.
Even as this happens, we cherish the concept of time in non-urban environments more than ever.
People and Nature
“Principle of environmental unity”: everything affects everything else
We depend on nature for many natural service functions
For a lot more information (and propaganda) on the impacts of overconsumption, see the International Buy Nothing Day Web site:
http://www.ecoplan.org/ibnd/ib_index.htm
Science and Values
Before we decide what kind of environment we want, we need to know what is possible.
Science is a process of discovery.
Sometimes changes in ideas are small.
Sometimes a science undergoes a fundamental revolution in ideas.
Science is one way of looking at the world.
It begins with observations about the natural world.
From these observations, scientists formulate hypotheses that can be tested.
Science does not deal with things that cannot be tested by observation, such as the following:
the ultimate purpose of life;
the existence of a supernatural being; or
standards of beauty or issues of good and evil.
Ideas are scientific if it is possible to disprove them.
What is Environmental Science?
A group of sciences that attempt to explain how life on Earth is sustained, what leads to environmental problems, and how these problems can be solved.
Often linked with nonscientific fields that have to do with how we value the environment (such as Deep Ecology).
Deals with many topics that have great emotional effects on people.
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Environmental science
… can help us avoid mistakes made by past civilizations.
On Easter Island, people annihilated their culture by
destroying their environment.
From The Science behind the Stories
Environmental science
… is an
interdisciplinary
field, drawing on
many diverse
disciplines.
Figure 1.6
Environmental science
… is NOT the same as
environmentalism.
It is science, NOT
advocacy.
Figure 1.7
Science
A systematic process for learning about the world and testing our understanding of it
A dynamic process of observation, testing, and discovery
And the accumulated body of knowledge that results from this process
Applications of science
Policy decisions and
management practices
are applications of science.
Prescribed burning, used to
restore forest ecosystems
altered by human
suppression of fire.
Figure 1.8a
Applications of science
Technology is another
application of science.
Energy-efficient
methanol-powered
fuel cell car from
DaimlerChrysler
Figure 1.8b
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Scientific method: Assumptions
Fixed natural laws govern how the universe works
All events arise from causes, and cause other events
We can use our senses and reason to detect and describe nature’s laws
Scientific method
A step-by-step method
for testing ideas with
observations.
Figure 1.9
Scientific Method
Observations are anything you can sense?
How do you sense things?
See, hear, smell, touch, taste
Scientific Method
Observations must be
Measurable
Repeatable
Controllable
Scientific Method
Hypotheses are tentative explanations of the observations or educated guesses.
Predictions result from hypotheses and are usually seen in the form of if then statements.
For example, My car won’t start is an observation. The battery in my car is dead is a hypothesis. If I replace my car battery with a brand new battery then it will start is a prediction.
Scientific method
Scientists use educated guesses called hypotheses to
generate predictions
that are then tested experimentally.
Results may reject or fail to reject a hypothesis.
Results never confirm a hypothesis, but only lend support to
it by failing to reject it. This means we never prove
anything with this method.
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Experiments
Manipulative experiments
are strongest.
Figure 1.10
Natural or correlational
ones are often necessary.
Scientific process
Peer review,
publication,
and debate are
parts of the
larger
scientific
process.
Figure 1.11
Hypothesis, theory, and paradigm
Hypothesis = an educated guess, to be tested
Theory = a well-tested and widely accepted explanation of the observations, validated by much previous research
Paradigm = a dominant view. May shift if new results show old results or assumptions to be wrong
Scientific Method
Feedback is the most important feature of the scientific method.
It allows for self reflection.
It lets us look at the data from different points of view.
It allows us to test different but related hypotheses.
It creates opportunities to find multiple reasons to confirm our hypothesis.
Positive Feedback: Off-road Vehicles (ORVs) and Erosion
Some situations involve both positive and negative
feedback
Example: changes in human populations of large cities
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Exponential growth
Exponential growth is an important outcome of positive feedback
Exponential growth is incompatible with sustainability
Solving Many Environmental Problems Involves Systems
and Rates of Change
A system is a set of parts that function together to act as a whole, like a city (streets, buildings, sewer systems) or a river (water sources, animals and plants in and along the river.
Changes and Equilibrium in Systems
When the input to a system is equal to the output, the system is said to be in a steady state
Steady state is a dynamic equilibrium because something is still happening
• If input is less than the output, the storage
compartment will shrink
– Groundwater extraction
• If input exceeds
output, the storage
compartment will
expand
– Groundwater
pollution
Environmental Unity
It is impossible to change only one thing; everything affects everything else
Changes in one part of a system often have secondary and tertiary effects within the system and effects on adjacent systems
See Wikipedia: Butterfly Effect and Wikipedia: A Sound of Thunder. Also see "The Butterfly Effect—Real?"
Placing a Value on the Environment
Utilitarian justification
values the environment it is useful economically or for survival.
Ecological justification
Values the larger life-support functions of the environment.
Aesthetic justification
values beauty.
Moral justification
based on one’s view of right and wrong, and extending inherent rights beyond humans.
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To effectively manage natural systems, we need to
understand:
– the types of disturbances and changes that are
likely to occur
– the time periods over which changes occur
– the importance of each change to the long-term
productivity of the system.
Biota: Biosphere and Sustaining Life
Biota: all living things (animals and plants, microorganisms) within a given area
Biosphere: the region of Earth where life exists
What is needed to sustain life?
there must be several species within a system that includes air and water to transport materials and energy – an ecosystem
Ecosystems
A community of organisms and their local nonliving environment in which matter (chemical elements) cycles and energy flows
Vary in size, from the smallest puddle of water to a large forest, or the entire global biosphere
Ecosystem borders may be clearly or vaguely defined
Environmental characteristics that make solving
problems harder
Lag time is the time between a stimulus and a system’s response to that stimulus
If there is a long delay between stimulus and response, then the resulting changes are much more difficult to recognize
Exponential Growth and Long Lag Time
Exponential growth and long lag time may allow a population to eventually exceed the carrying capacity, resulting in overshoot and a decline collapse in the population. Some environmental changes may be irreversible over time periods of hundreds or thousands of years
Ecological Footprint
Ecological footprint - the total area each person requires based on the resources used and the waste produced.
We may be consuming about 20% more of Earth’s biological productivity than is replaced each year.
Take the Ecological Footprint Quiz to determine your own ecological footprint.
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The Precautionary Principle: When in Doubt, Play It Safe
It can be difficult to prove with absolute certainty how human activities lead to local and global environmental problems.
When there is a threat of serious environmental damage, we should not wait for certain scientific proof before taking steps to prevent potential harm.
How much proof do we need before acting?
We need to examine the benefits and costs of taking a particular action versus taking no action.
The Precautionary Principle is a proactive tool.
More information on the Precautionary Principle.
Ethics
Ethics is a discipline that
deals with how we value
and perceive our
environment.
Ethics influence our
decisions and actions.
Figure 2.1
Worldview
Worldview = a person’s or group’s beliefs about the
meaning, purpose, operation, and essence of the world.
Some questions in environmental ethics
Should the present
generation conserve
resources for future
generations?
Is it OK to destroy a
forest to create jobs
for people?
Is it OK for some
communities to be
exposed to more
pollution than others?
Are humans justified
in driving other
species to extinction?
Environmental Ethics
Moral = the distinction between right and wrong
Values = the ultimate worth of actions or things
What is instrumental value?
What is intrinsic value?
Environmental Ethics
is concerned with the moral relationships between humans and the world around us.
Do we have special duties, obligations, or responsibilities to other species or nature in general?
Are our dispositions towards humans different than towards nature? How are they different?
Are there moral laws objectively valid and independent of cultural context, history, situation, or environment?
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Environmental Ethics
Universalists
Relativists
Nihilists
Utilitarians
Environmental Ethics
Universalists
Fundamental principles of ethics are universal, unchanging, and eternal.
The rules of right and wrong are valid regardless of our interests, attitudes, desires or preferences.
Revealed by God?
Revealed by discovery?
Plato, Kant
Environmental Ethics
Relativists
Moral principles are always relative to a particular person, society, or situation. Ethical values are contextual, that is they depend on the person, the society, or the situation. There is right and wrong or at least better or worse but no principles are absolute regardless of context.
Sophists
Environmental Ethics
Nihilists
The world makes no sense at all! Everything is completely arbitrary, there is no meaning or purpose to life other than the instinctive struggle for survival. There is no reason to behave morally. Might is right. The is no such thing as the good life. Life is uncertain full of pain and despair.
Schopenhauer
Environmental Ethics
Utilitarians
An action is right that produces the greatest good for the greatest number of people.
Goodness = Happiness Happiness = Pleasure
Bentham (Plato, Socrates, Aristotle)
John Stuart Mill held that the greatest pleasure is to be educated and to act according to enlightened, humanitarian principles
Environmental Perspectives (World views)
Worldview = a person’s or group’s beliefs about the meaning, purpose, operation, and essence of the world.
There are lots of them
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Three ethical worldviews
Figure 2.4
Environmental Perspectives
Domination
Stewardship
Biocentrism
Ecocentrism
Ecofeminism
Scientific Process
Sustainability
Critical Thinking
Environmental Perspectives
Domination
“Be fruitful, and multiply, and replenish the earth, and subdue it; and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth” Gen 1:28
Stewardship
Responsibility to manage and care for a particular place. As custodians of resources, they see their proper role as working together with human and nonhuman forces to sustain life.
Humility and reverence are essential in this worldview
Environmental Perspectives
Biocentrism
Life centered, all organisms have some intrinsic values and rights. Biodiversity is the highest ethical value in nature. Individuals and populations are the basic units of biodiversity.
Environmental Perspectives
Ecocentrism
Ecologically centered, because
individuals are doomed to suffering and pain
evolution, adaptation, and biogeochemical cycles are really more important than individuals.
The whole ecosystem is more important than the individuals and populations that make up the ecosystem.
Moral values for ecological process and systems
Environmental Perspectives
Ecofeminism
Western civilization in opposition to nature
life is interconnected
maintenance of diversity
restructuring human society
Bounty rather than scarcity
Cooperation rather than competition
A network of personal relationships rather than isolated egos
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Environmental Perspectives
The Scientific Process at work
1. Provides a linear path to knowledge with positive and negative feedback loops.
2. Requires repeated observation of the same thing, over and over again.
3. Some times repeated observations are not possible.
4. Need to be able to measure something. (testable?)
5. Need to be able to control things.
6. Need to be able to define things.
7. Can’t Prove something to be true only that it is false
8. Feedback goes on at each level in the scientific method.
Environmental Perspective
Sustainability
Refers to whether a process can be continued indefinitely without depleting the energy or material resources on which it depends. Sustainable agriculture maintains the integrity of the soil and water resources as well as genetic diversity of the germ plasm. Sustainable development provides people with a better life without sacrificing or depleting resources or causing environmental impacts that will undercut future generations. Sustainable society sustainable yield.
Environmental Perspective
Sustainability based on ecosystem processes
A recycling of elements
Sunlight as a source of energy
Carrying capacities are realized and maintained
Biodiversity is maintained
Environmental Perspectives
Critical Thinking
Elements of thought
Intellectual standards
Early environmental philosophers
The industrial revolution inspired reaction.
The preservation ethic
John Muir (right, with President Roosevelt at Yosemite)
advocated preserving unspoiled nature, for its own sake and
for human fulfillment.
Figure 2.5
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The conservation ethic
Gifford Pinchot advocated using natural resources, but
exploiting them wisely, for the greatest good for the greatest
number for the longest time.
Figure 2.6
The land ethic
Aldo Leopold urged people to view themselves as part of
nature, and to strive to maintain “the integrity, stability, and
beauty of the biotic community.”
Figure 2.7
Environmental justice (EJ)
Poor people and minorities suffer more than their share of environmental
problems, EJ advocates say.
The EJ movement began with a protest against a toxic waste dump in an
African-American community in North Carolina.
Figure 2.8
Sustainability
The key concept for our future:
Limiting human impact on the natural world so that our civilization can continue to exist
Sustainable development
UN: Development that “meets the needs of the present
without sacrificing the ability of future generations to meet
theirs”.
Figure 1.17
Sustainability
Use it, but don’t use it up
Other uses of the term "sustainability":
sustainable society
sustainable economy
sustainable development
sustainable architecture
More on sustainability at Wikipedia: Sustainability: http://en.wikipedia.org/wiki/Sustainability
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Earth’s Carrying Capacity
How many people can Earth sustain?
Carrying capacity is usually defined as the maximum number of individuals of a species that can be sustained by an environment over the long term.
Conclusions: Challenges
We live on a planetary island with limited resources.
Population and consumption are growing.
Many feel that we have not yet developed the ethical basis
for sustainability.
Environmental justice remains a challenge.
Conclusions: Solutions
We are developing ideas and technologies to lessen our
impacts.
We can reduce population and consumption.
Sustainability is catching on.
Science helps us understand our world and develop
solutions.
Conclusions: Solutions
Environmental science is vibrant and growing.
Ethics evolve, and we may yet develop an ethical basis
for sustainability.
Advances in technology and efficiency can mitigate our
environmental impacts.
Advances have been made toward environmental justice.
