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Environmental Science
Air Pollution
• Global climate change
• Stratospheric ozone depletion
• Urban air pollution• Acid deposition• Outdoor pollutants• Indoor pollutants• Noise
Biodiversity Depletion
• Habitat destruction• Habitat degradation• Extinction
Water Pollution
• Sediment• Nutrient
overload• Toxic chemicals
Infectious • agents• Oxygen
depletion• Pesticides• Oil spills• Excess heat
MajorEnvironmental
Problems
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.
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
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
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
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
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
ESP????
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.
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.
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 is 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?
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
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
Environmental PerspectivesThe 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
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
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.
QUESTION: Review
An anthropocentric worldview would consider the impact of an action on… ?
a. Humans only
b. Animals only
c. Plants only
d. All living things
e. All nonliving things
QUESTION: Review
Which ethic holds that people should use resources “for the greatest good for the greatest number for the longest time”?
a. Preservation ethic
b. Land ethic
c. Conservation ethic
d. Deep ecology
e. Biocentrism
QUESTION: Weighing the Issues
Which worldview is closest to your own?
a. Anthropocentric
b. Biocentric
c. Ecocentric
QUESTION: Review
Which is a nonrenewable natural resource?
a. Sunlight
b. Petroleum
c. Timber
d. Freshwater
QUESTION: Review
Which statement is FALSE?
a. Our environment includes living and nonliving elements.
b. Thomas Malthus favored population growth.
c. Environmental science includes multiple disciplines.
d. Theories are better supported by evidence than are hypotheses.
QUESTION: Review
Which is NOT an application of science?
a. Policy decisions
b. Technologies
c. Experimental results
d. Management practices
QUESTION: Weighing the Issues
What do you think is the best way to combat the “tragedy of the commons”?
a. Sell the commons into private hands, so owners have incentive to manage resources.
b. Have government regulate the amount of resources individuals take from the commons.
c. Have users work out cooperative systems among themselves to police resource use.
QUESTION: Interpreting Graphs and DataWhat happens if results fail to reject a hypothesis?
a. The hypothesis is proven to be true.
b. The hypothesis is supported, but not confirmed.
c. The hypothesis may be retested
in a different way, with new predictions.
d. Both b and c are true.Figure 1.9
