an introduction to environmental science chapters 1, 2, and 3

Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings

An Introduction to Environmental ScienceChapters 1, 2, and 3

Check out study tips at the end of the power point


Environment: the total of our surroundings

• All the things around us with which we interact:

• Living things (biotic factors)

• Animals, plants, forests, fungi, etc.

• Nonliving things (abiotic factors)

• Continents, oceans, clouds, soil, rocks

• Our built environment

• Buildings, human-created living centers

• Social relationships and institutions


Humans and the world around us• Humans change the environment, often in ways

not fully understood

• We depend completely on the environment for survival

- Increased wealth, health, mobility, leisure time

- But, natural systems have been degraded

- i.e., pollution, erosion and species extinction

- Environmental changes threaten long-term health and survival


Natural resources: vital to human survival

• Renewable resources:- Perpetually available: sunlight, wind, wave energy- Renew themselves over short periods: timber, water, soil

- These can be destroyed• Nonrenewable resources: can be depleted

- Oil, coal, minerals

Natural resources = substances and energy sources needed for survival


Environmental science is not environmentalism•Ecology

• The science that deals with the distribution and abundance of organisms and the interactions among them and other organisms.

•Environmental science is the study of:

- How the natural world works

- How the environment affects humans and vice versa

• The pursuit of knowledge about the natural world

• Scientists try to remain objective

•Environmentalism

• A social movement dedicated to protecting the natural world


Environmental science: how does the natural world work?Environment impacts Humans

• It has an applied goal: developing solutions to environmental problems

• An interdisciplinary field that incorporates:

-Natural sciences: information about the world

- Environmental Science programs

-Social sciences: values and human behavior

- Environmental Studies programs


The nature of science

• Science:- A systematic process for learning about the world

and testing our understanding of it- A dynamic process of observation, testing, and

discovery- The accumulated body of knowledge that results

from this process

• Science is essential

- To sort fact from fiction

- Develop solutions to the problems we face


Applications of science leads to

Restoration of forest ecosystems altered by human suppression of fire

Policy decisions and management practices

Energy-efficient methanol-powered fuel cell car from DaimlerChrysler

Technology


The scientific method

• A technique for testing ideas with observations

• Assumptions:- The universe works

according to unchanging natural laws

- Events arise from causes, and cause other events

- We use our senses and reason to understand nature’s laws


Controlled Experiments

• Controlled Experiments contain experimental and control groups.

• The experimental group is the group in the experiment that is identical to the control group except for one factor and is compared with controls group.

• The control group is the group in the experiment that serves as a standards of comparison with another group to which the control group is identical except for one factor.


Experiments test the validity of a hypothesis

Manipulative experiments yield the strongest evidence• But, lots of things can’t be manipulated


Experiments test the validity of a hypothesis

Natural tests show real-world complexity

• Results are not so neat and clean, so answers aren’t simply black and white


Correlations (natural test)

• If question is impossible or unethical, scientists test predictions by examining correlations or natural experiments.

• Correlation is the linear dependence between two variables.


With enough data, a paradigm shift – a change in the dominant view – can occur


DRY MIX is an acronym to help you remember how

variables are plotted on a graph.

•D = dependent variableR = responding variableY = graph information on the vertical axis

M = manipulated variable I = independent variableX = graph information on the horizontal axis


• Independent Variable or Manipulated Variable is what you are testing. It is what causes things to change as you make changes to it. Some people nickname it the I-do variable.

• Dependent Variable or the Responding Variable is the effect and it may or may not change. It is observed during as well as at the end of the experiment.


Global human population growth

• More than 6.7 billion humans

• Human population growth has shaped our relationship with natural resources.

• Current rate of population growth has slowed but is still growing at 1.23% a year.

• Estimated population for 2050 is 9.2 billion

• Population growth in developing

• countries is increasing 15 times

• faster than developed countries

• By 2050, 97% of growth will be

• in developing countries


How Many People Can the Earth Support?• We do not know how long we can continue increasing the earth’s

carrying capacity for humans without seriously degrading the life-support system for humans and many other species.


PERIODS OF HUMAN HISTORY AND POPULATION GROWTH

• Hunter-Gatherer

• Agriculture revolution

• Industrial revolution

• Technology revolution (globization)


Hunter-Gatherers (earliest humans)Survived by hunting animals and gathering wild plants. They were often nomadic.

POSITIVE OUTCOMES

• Population was usually small

• Expert Knowledge of the Natural World

NEGATIVE OUTCOMES

• High infant mortality rate

• Overharvested animals to point of extinction

• Altered ecosystems by distribution of seeds


Agricultural Revolution (10,000-12,000 years ago)Shift in human culture whereas, hunter-gatherers settled into agricultural communities. Domestication of animals and cultivation of plants occur. Main energy sources animal power (some water and wind power)

POSITIVE OUTCOMES• More food due to growing

crops• Support larger

populations• Higher standard of living

and life expectancy• Formed villages, towns,

etc.

NEGATIVE OUTCOMES• Cleared land for farming-

destruction of habitat and native wildlife

• Loss of soil fertility and increasing soil erosion

• More people in concentrated areas contributes to waste, pollution, diseases

• Power struggle for ownership of resources


Industrial Revolution (mid 1700’s until 1900’s)Human cultural shift from animal power to the use of fossil fuels and machinery. (Shift from renewable to nonrenewable resources)

POSITIVE OUTCOMES

• Mass production of useful and affordable goods.

• Increased agriculture production.

• Higher standard of living and life expectancy

• Lower infant mortality

• Moderate to high rate of population of growth

NEGATIVE OUTCOMES• Increased use and

dependency of nonrenewable resources

• Increased air pollution, water pollution

• Increased amount of waste products.

• Soil depletion and degradation;

• Habitat destruction; • Loss of biodiversity


Information/Globalization Revolution (1950’s until present)Humans are currently in process of social, economic, and environmental changes. This is characterized by sharing and integrating technology worldwide. Development of world-wide communication systems ( telephone, radio, computers, TV, satellites, Internet,)POSITIVE OUTCOMES

• Computer generated models of Earth systems

• Increased technology surveying and sensing environmental systems

• The ability to respond to environmental issues/problems more effectively

NEGATIVE OUTCOMES

• Information overload

• Globalized economy can increase environmental degradation

• Globalized economy can decrease cultural diversity


How Long Can the Human Population Keep Growing?

• Can the human population grow indefinitely?

- Population growth has slowed but we do not know how long we can continue without overshooting earth’s carrying capacity for humans.

- No population, including humans, can continue to grow indefinitely.


Studying human populations

• Demography is the study of the characteristics of populations, especially human populations.

• Demographers study the historical size and makeup of the population.

• They study properties that affect population growth such as economics and social structure.


Economic differences among countries

Unequal distribution of wealth and resources around the world influences environmental problems.

The U.N. generally classifies countries as either developed or developing.


Characteristics of Developing Countries

• lower average incomes

• simple agriculture-based communities

• rapid population growth

• African countries like Kenya and Ethiopia

• Indonesia

• India

CHARACTERISTICS COUNTRIES


Characteristics of Developed Countries

• United States

• Canada

• Japan

• Countries of Western Europe

CHARACTERISTICS COUNTRIES

• higher incomes

• slower population growth

• diverse industrial economies

• stronger social support.


• The human population in some areas is growing too quickly for the local environment to support. (POPULATION GROWTH)

• People are using up, wasting, or polluting many natural resources faster than they can be renewed, replaced, or cleaned up. (COMSUMPTION PRACTICES)

Almost all environmental problems can be traced back to two root

causes:


Problems associated with consumption practices

• To support the higher quality of life, developed countries are using much more of Earth’s resources.

• More of a problem in Developed Countries.

• This rate of consumption creates more waste and pollution per person than in developing countries.


• There may not be enough natural resources for the everyone to live a healthy, productive life.

• Many problems in Developing Countries result from population growth rate.

• In severely overpopulated regions, forests are stripped bare, topsoil is exhausted, and animals are driven to extinction.

• In these areas, malnutrition, starvation, and disease can be constant threats.

Problems associated with rapid population growth


The wealth gap and population growth cause conflict

• The stark contrast between affluent and poor societies causes social and environmental stress

• The richest 20% use 86% of the world’s resources- Leaves 14% of the

resources for 80% of the world’s people to share

• Tensions between “haves” and “have-not’s” are increasing



• Thomas Malthus and population growth: - In 1798, Malthus a British economist, hypothesized that

the human population tends to increase exponentially while food supply increases at a much slower rate.

- So far, Malthus has been proven wrong. Food production has increased exponentially due to technology advances.

- Many people believe that technological advances have allowed humans to avoid environmental resistance faced by other populations therefore increasing the carrying capacity for humans.


Thomas Malthus and human population

• Thomas Malthus

• Wrote An Essay on the Principle of Population

• Population growth must be restricted, or it will outstrip food production

• Starvation, war, disease



• Advocates for slowing population growth believe that because we now fail to provide the basic needs for 1 out of 5 people, how can we support future growth.

• They are concerned about increased death rates because declining health and environmental degradation.

• Also the increasing ecological footprint may increase resource use and further degradation.


• Neo-Malthusians

• Paul and Anne Ehrlich, The Population Bomb (1968)

• Population growth has disastrous effects leading to famine and conflict by the end of the 20th century


“The Tragedy of the Commons”

• In his essay, ecologist Garrett Hardin argued that the main difficulty in solving main difficulty in solving environmental problems is the conflict environmental problems is the conflict between the short-term interests of the between the short-term interests of the individual and the long-term welfare of individual and the long-term welfare of society.society.

• The example he used was the commons, or the areas of land that belonged to the whole village.


“Tragedy of the Commons”

• Hardin’s point can be applied to our modern commons, natural resources.

• Humans live in societies, and in societies, we can solve environmental problems by planning, organizing, considering the scientific evidence, and proposing a solution.

• The solution may be to override the short-term interests of the individual and improve the environment for everyone in the long run.


Avoiding mistakes made by past civilizations.

The lesson of Easter Island: people annihilated their culture by destroying their environment. Can we act more wisely to conserve our resources? http://channel.nationalgeographic.com/series/explorer/3829/Overview#tab-Videos/06769_00


The “ecological footprint”• Wackernagel and Rees

• The environmental impact of a person or population

- Amount of biologically productive land + water

- for raw materials and to dispose/recycle waste

• Overshoot: humans have surpassed the Earth’s capacity We are using 30% more of the planet’s resources than are available on a sustainable basis!


Ecological footprints are not all equal

• The ecological footprints of countries vary greatly

- The U.S. footprint is almost 5 times greater than the world’s average

- Developing countries have much smaller footprints than developed countries

- www.myfootprint.org


Population growth affects the environment

• The IPAT model: I = P x A x T x S

- Our total impact (I) on the environment results from the interaction of population (P), affluence (A) and technology (T), with an added sensitivity (S) factor

- Population = individuals need space and resources

- Affluence = greater per capita resource use

- Technology = increased exploitation of resources

- Sensitivity = how sensitive an area is to human pressure

- Further model refinements include education, laws, ethics


Natural Capital =Natural Resources + Natural Services• Natural Resources are materials and energy

essential to humans.

• Natural services include biochemical cycles (carbon, hydrogen, nitrogen, phosphorus) and energy transfer.

• Living sustainable means living off the interest of natural capital.


Culture and worldview

• Our relationship with the environment depends on assessments of costs and benefits

• Culture and worldview also affects this relationship

- Culture = knowledge, beliefs, values, and learned ways of life shared by a group of people

- Worldview = a person’s or group’s beliefs about the meaning, purpose, operation, and essence of the world

Culture and worldview affect our perception of the environment and environmental problems


Expanding ethical concern

• Why have we expanded our ethical concerns?

- Economic prosperity: more leisure time, less anxieties

- Science: interconnection of all organisms

• Non-western cultures often have broader ethical domains

• Three perspectives in Western ethics

- Anthropocentrism = only humans have rights

- Biocentrism = certain living things also have value

- Ecocentrism = whole ecological systems have value

- Holistic perspective, stresses preserving connections


Western ethical expansion


The preservation ethic

• Unspoiled nature should be protected for its own inherent value

• John Muir (right, with President Roosevelt at Yosemite

National Park) had an ecocentric viewpoint


The conservation ethic

• Use natural resources wisely for the greatest good for the most people

• Gifford Pinchot had an anthropocentric viewpoint


The land ethic

• Healthy ecological systems depend on protecting all parts

• Aldo Leopold believed the land ethic changes the role of people from conquerors of the land to citizens of it


Environmental systems support economies **why we study economics in environmental science• Ecosystem services = essential services support the life

that makes economic activities possible (these make jobs possible)

*Soil formation *Pollination

*Water purification *Nutrient cycling

*Climate regulation *Waste treatment

• Economic activities affect the environment

• Deplete natural resources

• Produce too much pollution


Classical economics

• Adam Smith —considered the father of economics; free market and supply/demand

• Competition between people free to pursue their own economic self-interest will benefit society as a whole (Adam Smith, 1723-1790)

• This idea is a pillar of free-market thought today

• It is also blamed for economic inequality

• Rich vs. poor

• Critics think that market capitalism should be restricted by government


Neoclassical economics• Examines the

psychological factors underlying consumer choices

• Market prices are explained in terms of consumer preferences

• The “right” quantities of a product are produced

The market favors equilibrium between supply and demand


Costs and Benefits• The cost of environmental solutions can be

high.• A cost-benefit analysis balances the cost of

the action against the benefits one expects from it.

• The results depend on who is doing the analysis. For example, pollution control may be too costly to an industry, but to a nearby community, the price may well be worth it.

• Often, environmental regulations are passed on to the consumer or taxpayer.


Early U.S. environmental policy• Involved management of

public lands, 1780s to the late 1800s

• Promoted settlement

• Extraction of natural resources

• Increased prosperity

• Relieved crowding in Eastern cities

• Displaced millions of Native Americans

• People believed that land was infinite and inexhaustible


The second wave of U.S. policy

• Addressed impacts caused by the first wave

• Public perception and government policy shifted

• Mitigated environmental problems associated with westward expansion

• Yellowstone National Park, the world’s first national park, opened in 1872

• Other protected areas were created

• National wildlife refuges, parks, and forests • Reflected a new understanding that the West’s

resources were exhaustible and required legal protection


The third wave of U.S. environmental policy

• Policy = a formal set of general plans and principles to address problems and guide decisions

• Public Policy = policy made by governments that consists of laws, regulations, orders, incentives, and practices

• Environmental Policy = pertains to human interactions with the environment

• Regulates resource use or reduce pollution


The third wave of U.S. environmental policy

• Mid-to late-20th century

• Better off economically

• But dirtier air, dirtier water, and more waste and toxic chemicals

• Increased awareness of environmental problems shifted public priorities and policy

• 1962: Silent Spring (by Rachel Carson) described the negative ecological and health effects of pesticides and industrial chemicals


Modern U.S. environmental policy• The Cuyahoga River was

polluted with oil and industrial waste

• It caught fire in the 1950s and 1960s

• Today, public enthusiasm for environmental protection remains strong

• The majority of Americans favor environmental protection

• In April, millions of people celebrate Earth Day


The National Environmental Policy Act (NEPA)

• 1970 began the modern era of environmental policy

• Created the Council on Environmental Quality

- Requires an Environmental Impact Statement (EIS) for any federal action that might impact the environment

NEPA forces the government and businesses to evaluate the environmental impacts of a project


The EPA shifts environmental policy

• Nixon created the Environmental Protection Agency (EPA)

• Conducts and evaluates research

• Monitors environmental quality

• Sets and enforces standards for pollution levels

• Assists states in meeting standards and goals

• Educates the public


Significant environmental laws• The public demanded a cleaner environment and supported

tougher environmental legislation


Why are environmental laws unpopular?

• Environmental laws are challenged, derided, and ignored

• Environmental policy involves government regulations

• Businesses and individuals view laws as overly restrictive and unresponsive to human needs

• Most environmental problems are long-term processes

• Human behavior is geared toward short-term needs

• News media have short attention spans • Politicians act out of their own short-term interest


• Results from actions of the three branches of government

• Legislative branch = creates statutory law

• Executive branch = enacts or vetoes legislation

- Issues executive orders

• Judicial branch = interprets laws

• Administrative agencies = the “fourth branch”

- Established by the president or Congress

Framework of U.S. policy


State and local policies affect environmental issues

• Important environmental policy is also created at the state and local levels

• State laws cannot violate principles of the U.S. Constitution,

• If laws conflict, federal laws take precedence

• California, New York, and Massachusetts have strong environmental laws

• The interior western states put less priority on environmental protection and favor unregulated development


Approaches to environmental policy

• Command-and-control approach: environmental policy sets rules or limits and threatens punishment for violators

• Heavy-handed

• Alternative approaches involve using economic incentives to encourage desired outcomes and use market dynamics to meet goals

• Most current environmental laws

- Have resulted in safe, healthy, comfortable lives


Drawbacks of command-and-control

• Government actions may be well-intentioned but not informed

• Interest groups–people seeking private gain–unduly influence politicians

• Citizens may view policies as restrictions on freedom

• Costly and less efficient in achieving goals


Widespread economic policy tools

• Tax breaks = encourage desirable industries or activities

• Subsidy = a government giveaway of cash or resources to encourage a particular activity

• Have been used to support unsustainable activities

In 2003, $58 billion of taxpayer’s money was spent on 68 environmentally harmful subsidies such as building logging roads


Another economic policy tool

• Green taxes = taxes on environmentally harmful activities

• Polluter pays principle = the price of a good or service includes all costs, including environmental degradation

• Gives companies financial incentives to reduce pollution

• But, costs are passed on to consumers


Market permitting and incentives• Permit trading = government-created market in

permits

• Businesses buy, sell, trade these permits

• Emissions trading system = government-issued permits for an acceptable amount of pollution and companies buy, sell, or trade these permits with other polluters

• Cap-and-trade system = a party that reduces its pollution levels can sell this credit to other parties

- Pollution is reduced overall, but does increase around polluting plants

• Companies have an economic incentive to reduce emissions


Sustainability: a goal for the futureSustainability - Leaves future

generations with a rich and full Earth

- Conserves the Earth’s natural resources

- Maintains fully functioning ecological systems

• Sustainable development: the use of resources to satisfy current needs without compromising future availability of resources


Four scientific principles of sustainability

• reliance of solar energy

- -provides warmth

- -provides energy for photosynthesis

- -provides energy for all life systems

• biodiversity

- -variety of organisms

- -demonstrates life’s ability to adapt

• nutrient cycling

- -provides and recycles chemicals needed for life

- -little or no waste in natural systems

• population control

- -competition limits population growth


Will we develop in a sustainable way?

• The triple bottom line: sustainable solutions that

meet- Environmental goals- Economic goals- Social goals

• Requires that humans apply knowledge from the sciences to- Limit environmental impacts - Maintain functioning

ecological systems


Study tips• Read chapter 1,2,3 **look throughout

chapters at diagrams, graphs, pictures that I mentioned during lecture.

• Study your notes--

• Think about the main idea of the Tragedy of Commons Activity (M & M activity) and the Easter Island video.

• Study multiple choice worksheet---these were sample questions—not the test questions—but similar

• Study practice Free Response Question


Key charts, diagrams and etc. found in your textbook

• Fig. 1-1 pg 4

• Fig 1-9 pg 12

• Fig. 1-12 pg 17

• Table 2-2 pg 40

• Fig. 2-12 (a) pg 41


Do You know the difference between..?

• Abiotic factors and Biotic factors

• Renewable and nonrenewable resources

• Ecology, environmental science and environmentalism

• Dependent and independent variables

• Controlled experiment, manipulative experiment, natural experiment

• Developed and developing countries

• Anthropocentric, biocentric, ecocentric


Do you know examples of…?

• Abiotic factors and Biotic factors

• Renewable and nonrenewable resources

• Developed and developing countries

• Anthropocentric, biocentric, ecocentric


Do you know the contribution(s) of the following?• Adam Smith

• Thomas Malthus

• Paul and Anne Ehrlichs

• Garrett Hardin

• Wackernagel and Rees

• Rachel Carson

• Richard Nixon


Environmental Impact created by …

• Hunter-Gatherers

• Agricultural Revolution

• Industrial Revolution

• Developed countries

• Developing countries


Do you know how the environment effects the economic? How does the economic affect environment?

• Know economic tools

- Subsidies

- Tax breaks

- Green Taxes

- Permit trading

an introduction to environmental science chapters 1, 2, and 3

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