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Tools To Study The Environment
• The nature of
environmental science
Scott Brennan • Jay Withgott
Unit 1: We and Our Environment
Fundamental Environmental Issues
Dr. Manish Kumar
Dept of Environ. Science
manishk@tezu.ernet.in
• The scientific method
and the scientific
process
• Natural resources and
their importance
• Culture and
worldviews
• Environmental ethics
Big Question: Why Is Science Necessary to Solve
Environmental Problems?
The “environment”
• Sustainability
Definitions: (Ironically not always defined…;-)
Consists of both:
Biotic factors (living things) and
Abiotic factors (nonliving
things) that surround us and with which
we interact.
Humans and the environment
Natural resources
• 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.
• Renewable resources like sunlight cannot be depleted.
• Thus, our interactions with our environment matter a
great deal.
• 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
Thomas Malthus (1766-1834)
Population growth will
lead to starvation, war,
disease.
• Our population has
skyrocketed to over
6 billion.
Death rates check
population unless birth
rates are lowered.
• The agricultural and
industrial revolutions
drove population
growth.
In our day, Paul Ehrlich
(The Population Bomb,
1968) is called
“neo-Malthusian.”
Figure 1.2
Figure 1.3
What should we do about the environment?
The tragedy of the commons
If you’re not part
of the solution….
Garrett Hardin, 1968:
Pollution
Global warming
Greenhouse effect
In a “commons” open
to all, unregulated use
will deplete limited
resources.
Slash and burn
Animal extinction
…you’re part
of the
problem.
Figure 1.4
Environmental science
What is an “environmental problem?”
How does the natural world work?
Definitions differ.
The pesticide DDT:
How does our environment affect us?
was thought safe in
1945
How do we affect our environment?
is known to be toxic
today
Applied goal: Developing solutions to environmental
problems.
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.
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 nonurban environments more than ever.
See the Wikipedia article: Think Globally, Act Locally.
People and Nature
Science and Values
“Principle of environmental unity”: everything affects
everything else
Before we decide what kind of environment we want, we
need to know what is possible.
We depend on nature for many natural service functions
Science is a process of discovery.
Sometimes changes in ideas are small.
For a lot more information (and propaganda) on the impacts
of overconsumption, see the International Buy Nothing Day
Web site:
Sometimes a science undergoes a fundamental revolution
in ideas.
http://www.ecoplan.org/ibnd/ib_index.htm
Science is one way of looking at the world.
What is Environmental Science?
It begins with observations about the natural world.
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.
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;
Often linked with nonscientific fields that have to do with
how we value the environment (such as Deep Ecology).
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.
Deals with many topics that have great emotional effects on
people.
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Environmental science
Environmental science
… can help us avoid mistakes made by past civilizations.
On Easter Island, people annihilated their culture by
destroying their environment.
… is an
interdisciplinary
field, drawing on
many diverse
disciplines.
From The Science behind the Stories
Environmental science
Figure 1.6
Science
A systematic process for learning about the world and
testing our understanding of it
… is NOT the same as
environmentalism.
A dynamic process of observation, testing, and discovery
It is science, NOT
advocacy.
And the accumulated body of knowledge that results from
this process
Figure 1.7
Applications of science
Applications of science
Policy decisions and
management practices
are applications of science.
Technology is another
application of science.
Energy-efficient
methanol-powered
fuel cell car from
DaimlerChrysler
Prescribed burning, used to
restore forest ecosystems
altered by human
suppression of fire.
Figure 1.8a
Figure 1.8b
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Scientific method: Assumptions
Scientific method
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
A step-by-step method
for testing ideas with
observations.
Figure 1.9
Scientific Method
Scientific Method
Observations are anything you
can sense?
Observations must be
How do you sense things?
See, hear, smell, touch, taste
Measurable
Repeatable
Controllable
Scientific Method
Scientific method
Hypotheses are tentative explanations of the observations or
educated guesses.
Scientists use educated guesses called hypotheses to
generate predictions
that are then tested experimentally.
Predictions result from hypotheses and are usually seen in
the form of if then statements.
Results may reject or fail to reject a hypothesis.
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.
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.
Scientific process
Natural or correlational
ones are often necessary.
Peer review,
publication,
and debate are
parts of the
larger
scientific
process.
Figure 1.11
Figure 1.10
Hypothesis, theory, and paradigm
Scientific Method
Feedback is the most important
feature of the scientific method.
Hypothesis = an educated guess, to be tested
It allows for self reflection.
Theory = a well-tested and widely accepted explanation of
the observations, validated by much previous research
It lets us look at the data from
different points of view.
Paradigm = a dominant view. May shift if new results
show old results or assumptions to be wrong
Positive Feedback: Off-road Vehicles (ORVs) and Erosion
It allows us to test different but
related hypotheses.
It creates opportunities to find
multiple reasons to confirm our
hypothesis.
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
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
Environmental Unity
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.
• 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
Placing a Value on the Environment
Utilitarian justification
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?"
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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Biota: Biosphere and Sustaining Life
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: all living things (animals
microorganisms) within a given area
and
plants,
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
Environmental characteristics that make solving
problems harder
A community of organisms and their local nonliving
environment in which matter (chemical elements) cycles
and energy flows
Lag time is the time between a stimulus and a system’s
response to that stimulus
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
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
Ecological Footprint
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 - 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.
Ethics
Ethics is a discipline that
deals with how we value
and perceive our
environment.
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.
Ethics influence our
decisions and actions.
More information on the Precautionary Principle.
Figure 2.1
Worldview
Some questions in environmental ethics
Should the present
generation conserve
resources for future
generations?
Worldview = a person’s or group’s beliefs about the
meaning, purpose, operation, and essence of the world.
Is it OK to destroy a
forest to create jobs
for people?
Environmental Ethics
Are humans justified
in driving other
species to extinction?
Is it OK for some
communities to be
exposed to more
pollution than others?
Environmental Ethics
is concerned with the moral relationships between humans
and the world around us.
Moral = the distinction between right and wrong
Values = the ultimate worth of actions or things
What is instrumental value?
What is intrinsic value?
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
Environmental Ethics
Universalists
Universalists
Relativists
Fundamental principles of ethics are universal, unchanging,
and eternal.
Nihilists
The rules of right and wrong are valid regardless of our
interests, attitudes, desires or preferences.
Utilitarians
Revealed by God?
Revealed by discovery?
Plato, Kant
Environmental Ethics
Environmental Ethics
Relativists
Nihilists
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.
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.
Sophists
Schopenhauer
Environmental Ethics
Environmental Perspectives (World views)
Utilitarians
An action is right that produces the greatest good for the
greatest number of people.
Goodness = Happiness Happiness = Pleasure
Worldview = a person’s or group’s beliefs about the
meaning, purpose, operation, and essence of the world.
Bentham (Plato, Socrates, Aristotle)
John Stuart Mill held that the greatest pleasure is to be
educated and to act according to enlightened,
humanitarian principles
There are lots of them
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Three ethical worldviews
Environmental Perspectives
Domination
Stewardship
Biocentrism
Ecocentrism
Ecofeminism
Scientific Process
Sustainability
Critical Thinking
Figure 2.4
Environmental Perspectives
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.
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.
Humility and reverence are essential in this worldview
Environmental Perspectives
Environmental Perspectives
Ecofeminism
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
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
Environmental Perspective
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
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.
8. Feedback goes on at each level in the scientific method.
Environmental Perspective
Environmental Perspectives
Sustainability based on ecosystem processes
A recycling of elements
Critical Thinking
Sunlight as a source of energy
Elements of thought
Carrying capacities are realized and maintained
Intellectual standards
Biodiversity is maintained
Early environmental philosophers
The preservation ethic
The industrial revolution inspired reaction.
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
The land ethic
Gifford Pinchot advocated using natural resources, but
exploiting them wisely, for the greatest good for the greatest
number for the longest time.
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
Figure 2.6
Environmental justice (EJ)
Sustainability
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.
The key concept for our future:
Limiting human impact on the natural world so that our
civilization can continue to exist
Figure 2.8
Sustainable development
Sustainability
UN: Development that “meets the needs of the present
without sacrificing the ability of future generations to meet
theirs”.
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
Figure 1.17
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Earth’s Carrying Capacity
Conclusions: Challenges
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.
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.
Conclusions: Solutions
Environmental science is vibrant and growing.
Sustainability is catching on.
Ethics evolve, and we may yet develop an ethical basis
for sustainability.
Science helps us understand our world and develop
solutions.
Advances in technology and efficiency can mitigate our
environmental impacts.
Advances have been made toward environmental justice.
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