An introduction to environmental science 1 An introduction to environmental science

This lecture will help you understand: 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) & Abiotic factors (nonliving things) that surround us and with which we interact. “Even Obi-wan Kenobi knew that much...”

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

“The tragedy of the commons!” Garrett Hardin, 1968: In a “commons” open to all, unregulated use will deplete limited resources. Figure 1.4

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 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.

Experiments Manipulative experiments are strongest. Natural or correlational ones are often necessary. Figure 1.10

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, validated by much previous research Paradigm = a dominant view. May shift if new results show old results or assumptions to be wrong

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? Are humans justified in driving other species to extinction? 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?

Three ethical worldviews Figure 2.4

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 Data What 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