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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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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! © 2015 Pearson Education, Inc. 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) © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. Frequently Asked Question • Aren’t environmental scientists also environmentalists? • Explain how they are similar and different. © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. Applications of science Engineering and technology Energy-efficient electric car © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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) © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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? © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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? © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. Three ethical perspectives (cont’d) • Ecocentrism • Whole ecological systems have value • Values well-being of species, communities, ecosystems • Holistic: it preserves connections between entities © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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? © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. Earth’s natural capital is like a bank account (cont’d) © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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? © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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) © 2015 Pearson Education, Inc. 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 © 2015 Pearson Education, Inc. 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.