Download Environmental science

Chapter
1
Science and
Sustainability: An
Introduction to
Environmental
Science
© 2015 Pearson Education, Inc.
Lecture Presentations prepared by
Reggie Cobb
Nash Community College
This lecture will help you understand:
•  The field of environmental science
•  The importance of natural resources and
ecosystem services
•  Population growth and resource consumption
•  The scientific method and the
process of science
•  Environmental ethics
•  Global environmental pressures
•  Concepts of sustainability and sustainable
development
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Our island, Earth
•  The Earth may seem enormous to us
•  But Earth and its systems are finite and limited
•  We can change Earth and damage its systems
•  Environment
•  All the living and nonliving things around us
•  Environmental science is the study of:
•  How the natural world works
•  How the environment affects humans and vice versa
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We rely on natural resources
•  Natural resources
•  Substances and energy sources we need for survival
•  Renewable natural resources
•  Replenished over short periods
•  Nonrenewable natural resources
•  Unavailable after depletion
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We rely on ecosystem services
•  Ecosystem services
•  Arise from the normal functioning of natural services and
allow us to survive
•  Ecological systems
•  Purify air and water, cycle nutrients, regulate climate,
pollinate plants, recycle waste
•  Degradation of ecosystem services
•  Occurs when we exhaust resources, destroy habitat,
generate pollution
•  Intensified by human affluence and population growth
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Population growth amplifies our impact
•  There are now over 7 billion humans
•  Two major phenomena triggered human population
increases
•  Agricultural revolution
•  10,000 years ago
•  Industrial revolution
•  mid 1700s
•  Demand for fossil fuels
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Resource consumption exerts pressures
•  Ecological footprint
•  The area of biologically
productive land and water
to provide resources and
dispose/recycle waste
•  We are using renewable
resources 50% faster
than they are being
replenished
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Overshoot
•  Overshoot
•  When humans have surpassed Earth’s capacity to
sustainably support us
It would take 1.5 years for the planet to regenerate renewable
resources people use in 1 year!
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Environmental science can help us avoid past
mistakes
•  Civilizations have fallen when population growth
and consumption overwhelm resource availability
•  Easter Island (The Science Behind the Story)
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The nature of environmental science
•  Environmental scientists
•  Research and develop solutions to environmental
problems
•  The solutions are applications of environmental science
•  The study of these applications is also part of environmental
science
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Environmental science is interdisciplinary
•  Environmental science involves input from multiple
disciplines
•  Natural sciences
•  Examine the natural world
•  Environmental science
programs
•  Social sciences
•  Examine human
interactions and institutions
•  Environmental studies
programs
© 2015 Pearson Education, Inc.
Environmental science is not the same as
environmentalism
•  Environmental science
•  The scientific study of the environment and our
interactions with it
•  Scientists try to remain objective and free from bias,
personal values, preconceptions
•  Environmentalism
•  A social movement dedicated to protecting the natural
world from undesirable changes due to human actions
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Frequently Asked Question
•  Aren’t environmental scientists also
environmentalists?
•  Explain how they are similar and different.
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The nature of science
•  Science
•  A systematic process for learning about the world and
testing our understanding of it
•  The body of knowledge arising from the dynamic process
of questioning, observation, testing, and discovery
•  Scientists are motivated to:
•  Develop useful applications
•  Understand how the world works
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Applications of science
Engineering and technology
Energy-efficient electric car
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Policy and management
Prescribed burning restores
healthy forests
Science tests ideas by critically examining
evidence
•  Observational (descriptive) science
•  Information is gathered about organisms, materials,
systems, or processes not yet well known
•  Phenomena are observed and measured
•  Used in astronomy, paleontology, taxonomy, molecular
biology, and genomics
•  Hypothesis-driven science
•  Targeted, structured research
•  Experiments test hypotheses using the scientific method
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The scientific method is a traditional approach
•  Testing ideas with observations
•  Observations lead to
questions about some
phenomenon
•  Hypothesis
•  A statement that tries to
answer the question
•  The hypothesis generates
predictions
•  Scientists test predictions by
conducting experiments
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The scientific method is a traditional approach
(cont’d)
•  Experiment
•  Tests the validity of a prediction
or hypothesis
•  Involves manipulating variables
•  Analyze and interpret results
•  Record data
•  Either reject the hypothesis or
generate a new hypothesis to
further test the original
hypothesis
•  Repetition is necessary
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Experiments manipulate variables
•  Independent variable
•  Can be manipulated
•  Dependent variable
•  Depends on the independent variable
•  Controlled experiment
•  Control
•  An unmanipulated point of comparison
•  Treatment
•  A manipulated point of comparison
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We test hypotheses in different ways
•  Manipulative experiments
•  The independent variable is manipulated
•  Reveal causal relationships
•  Provide the strong evidence
•  Long-term, large-scale processes can’t be manipulated
•  Natural tests
•  Compare how dependent variables are expressed in
naturally different contexts
•  Search for correlations among variables
•  Weaker evidence, but shows real-world complexity
•  Addresses immense-scale questions (i.e., ecosystems)
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The scientific process continues beyond the
scientific method
•  Peer review
•  Other scientists judge
the work
•  Conferences
•  Scientists interact with others
•  Grants and funding
•  From private or government
sources
•  Intense competition
•  Repeatability
•  Others try to reproduce the results
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Weighing the Issues
•  Follow the Money
•  Let us say you are a research scientist wanting to study
the impacts of chemicals released into lakes by pulpand-paper mills. Obtaining research funding has been
difficult. Then a large pulp-and-paper company contacts
you and offers to fund your research examining how its
chemical effluents affect water bodies.
•  What are the benefits and drawbacks to this offer?
•  Would you accept the offer?
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Theories and paradigm shifts
•  Theory
•  A well-tested and widely accepted explanation
•  Extensively validated by great amounts of research
•  Consolidates widely supported, related hypotheses
•  It is not “just a theory” (speculation)
•  Example: Darwin’s theory of evolution by natural
selection
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Theories and paradigm shifts (cont’d)
•  Paradigm
•  A dominant view
•  Paradigm shift
•  A new dominant view replaces the old
•  Example: Earth, not the sun, is the center of the universe
© 2015 Pearson Education, Inc.
Environmental ethics
•  Ethics
•  The set of moral principles or values held by a person or
society that tell us how we ought to behave
•  Relativists vs. universalists
•  Relativists: ethics varies with social context
•  Universalists: notions of right or wrong remain the same
across cultures and situations
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Environmental ethics (cont’d)
•  Ethical standards
•  Criteria that help differentiate right from wrong
•  Example: categorical imperative: the “Golden Rule,”
which tells us to treat others as we want to be treated
•  Example: principle of utility: the utilitarian principle holds
that something is right when it produces the greatest
practical benefit for the most people
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Environmental ethics pertains to people and the
environment
•  Environmental ethics
•  Application of ethical standards to relationships between
human and nonhuman entities
•  Hard to resolve: it depends on the person’s ethical
standards and domain of ethical concern
Should we conserve
resources for future
generations?
Should we drive other
species to extinction?
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Is it OK to destroy a
forest to create jobs
for people?
Is it OK for some
communities to be exposed
to excess pollution?
Three ethical perspectives
•  Anthropocentrism
•  Only humans have rights
•  Costs/benefits are measured only by their impact on
people
•  Anything not providing
benefit to people has no
value
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Three ethical perspectives (cont’d)
•  Biocentrism
•  Certain living things have value
•  All life (human and nonhuman) has ethical standing
•  Opposes development
that destroys life, even if
it increases food
production and economic
growth
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Three ethical perspectives (cont’d)
•  Ecocentrism
•  Whole ecological systems have value
•  Values well-being of species, communities, ecosystems
•  Holistic: it preserves
connections between
entities
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Conservation and preservation arose with the
20th century
•  Preservation ethic
•  Nature deserves protection for its own inherent value
•  We should protect our environment in a pristine,
unaltered state
John Muir’s (right, with
President Roosevelt)
ecocentric viewpoint
advocated for the
preservation of wilderness
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Conservation and preservation arose with the
20th century (cont’d)
•  Conservation ethic
•  A call to use natural resources wisely
•  A utilitarian standard that calls for using resources for the
greatest good for the most people for the longest time
Gifford Pinchot’s
anthropocentric viewpoint
promoted prudent, efficient,
sustainable use of resources
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Aldo Leopold’s land ethic inspires many people
•  Land ethic
•  Healthy ecological systems depend on protecting all
parts
•  We are obligated to treat the land ethically
Aldo Leopold’s ecocentric ethical
outlook calls for people to view
themselves and the land as
members of the same community
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Environmental justice seeks fair treatment for
all people
•  Environmental justice
•  Involves the fair treatment of all people with respect to
the environment, regardless of income, race, or ethnicity
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Weighing the Issues
•  Environmental Justice?
•  Consider the place where you grew up
•  Where were the factories, waste dumps, and polluting
facilities located?
•  Who lives nearest them in the town or city that hosts your
campus?
•  Do you think the concerns of environmental justice
advocates are justified?
•  If so, what could be done to ensure that poor
communities do not suffer more hazards that wealthy
ones?
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Sustainability and our future
•  Sustainability
•  Living within our planet’s means
•  Leaving our descendants with a rich, full world by:
•  Conserving resources for future generations
•  Developing solutions that work in the long term
•  Keeping fully functioning ecological systems
•  Sustainability is a guiding principle of modern
environmental science
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Earth’s natural capital is like a bank account
•  Natural capital (the bank account)
•  the accumulated wealth of Earth’s resources
•  We need to leave the principle intact and spend just
the interest
•  Depleting the principle decreases the bank account
•  Currently we are drawing down Earth’s natural
capital 50% faster than it is being produced
•  We cannot do this for long
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Earth’s natural capital is like a bank account
(cont’d)
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Population and consumption drive
environmental impact
•  Human population growth amplifies all
environmental impacts
•  We add over 200,000 people to the planet each day
•  Our consumption of resources has risen even faster
•  Life has become more pleasant for us
•  But rising consumption increases the demands we make
on our environment
•  Increased affluence has not been equal
•  The gap between rich and poor countries has tripled in
the past 40 years
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Population and consumption drive
environmental impact (cont’d)
•  The ecological footprints
of countries vary greatly
•  The U.S. footprint is much
greater than those of
developing countries
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Weighing the Issues
•  Leaving a Large Footprint
•  What do you think accounts for the variation in per capita
ecological footprints among societies?
•  Do you feel that people with larger footprints have an
ethical obligation to reduce their environmental impact,
so as to leave more resources available for people with
smaller footprints?
•  Why or why not?
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Population and consumption drive
environmental impact (cont’d)
•  Environmental impacts
•  Erosion from agriculture
•  Deforestation
•  Toxic substances
•  Mineral extraction and mining
•  Depletion of fresh water
•  Air and water pollution
•  Global climate change
•  Loss of Earth’s biodiversity
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The Millennium Ecosystem Assessment
•  The most comprehensive scientific assessment of
the condition of the world’s ecological systems and
their capacity to continue supporting us
•  In 2005, over 2000 leading environmental scientists
from nearly 100 nations found:
•  Our degradation of environmental systems is having
negative impacts on all of us
•  With care and diligence we can still turn many of these
trends around
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Energy choices will shape our future
•  Fossil fuels
•  Intensify the impact we exert on the environment
•  Have powered the machinery of the industrial revolution
•  However, we have depleted roughly half the world’s
conventional oil supplies
•  Possible new fossil fuel sources
•  Have more environmental impact while providing less fuel
•  Examples: hydraulic fracturing, oil sands extraction, deepwater and Arctic drilling
•  Our current choices greatly influence our lives in the
future
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Sustainable solutions abound
•  Sustainable solutions must:
•  Enhance quality of life
•  Protect/restore the environment that supports us
•  Many workable solutions exist
•  Renewable energy sources to replace fossil fuels
•  Energy-efficiency efforts
•  Improved agricultural practices
•  Laws and new technologies to reduce air pollution
•  Habitat and species protection
•  Better waste management to conserve resources
•  Reduced emissions of greenhouse gases
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Sustainable solutions abound (cont’d)
•  Sustainable development
•  Use of resources for economic advancement in a
manner that satisfies our current needs
•  But leaves enough resources for the future
•  Local level
•  Every individual person can help create sustainable
solutions in his/her community
© 2015 Pearson Education, Inc.
Students are promoting solutions on campus
•  Campus sustainability
•  Reducing ecological footprints
•  Sustainable solutions include:
•  Running recycling programs
•  Promoting efficient transportation options
•  Planting trees and restoring native plants
•  Growing organic gardens
•  Fostering sustainable dining halls
•  Improving energy efficiency and water conservation
•  Reducing greenhouse emissions
•  Investing in renewable energy
© 2015 Pearson Education, Inc.
Students are promoting solutions on campus
(cont’d)
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Environmental science prepares you for the
future
•  Environmental science courses
•  Prepare you for a lifetime in a world of increasing
sustainability concerns
•  Equip you with better understanding of how the world
works
•  Better prepare you for green-collar job opportunities of
today and tomorrow
•  Help you navigate the many sustainable future
challenges
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Conclusion
•  Finding ways to live sustainably on Earth requires:
•  A solid ethical grounding
•  Scientific understanding of our natural and social
systems
•  Environmental science helps us:
•  Understand our relationship with the environment
•  Informs our attempts to solve and prevent problems
•  Identifying a problem is the first step in solving it
•  Environmental science can help find balanced,
workable, sustainable solutions to environmental
problems
© 2015 Pearson Education, Inc.