sgcep scie 1121 environmental science spring 2012 section ...stevet/sgcep/sci1121/1.whatis... ·...

SGCEP SCIE 1121 Environmental Science

Spring 2012Section 20531

Steve Thompson: [email protected]://www.bioinfo4u.net/

1Wednesday, January 11, 2012

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CHAPTER 1: Science and the Environment — An introduction to environmental science

On Easter Sunday, 1722, Dutch sailors named a remote South Pacific island Easter Island It is the most remote spot on the planet

Inhabited by Polynesians who were living primitively

The sailors found large stone statues on the island

Evidence of a sophisticated civilizationThe past culture and civilization had vanished


Easter Island once had a prosperous culture


Easter Island: the pastPolynesians arrived on the island around 1200 A.D.It’s an environmentally fragile island

Small, isolated, dry, cold, nutrient-poor At first, it was abundantly forested

Palms, conifers, and sandalwoodThe inhabitants cut trees to

Clear land for agricultureProvide structural materialsMove the stone heads from the quarries to the sites at which they would be erected


Easter Island: an environmental catastrophe

By 1650, all the trees were gone The soil washed into the seaThe eroded soil baked, decreasing agriculture

Degraded soil, depleted forest and water resources Existence became harder Workers revolted against the ruling religious elitesWorkers fought among themselves

Starvation and disease became epidemicWithout trees, no one could leave the island by boatThe population was down to a few thousand by 1722


Easter Island: consequences of degradation

Easter Islanders (Rapa Nui) did not anticipate the consequences of their actions They also suffered terribly from their contacts with the “civilized” world

Visiting whalers infected them with venereal diseasesPeruvian slavers captured them for the slave trade Smallpox killed many peopleBy 1877 only 111 Rapa Nui remained!

After annexation by Chile, the government enclosed the Rapa Nui in one village


Easter Island: however, conditions have improved

In the mid–20th century, archaeologists brought attention to the islandStone statues have been restoredThe Rapa Nui regained some control over their destiny

Tourism has developed But they still depend on imported food

Unemployment and alcoholism are serious problems


Lessons from Easter Island When the following occur:

A society does not care for its environmentIts population increases beyond the capacity of the land and water to provide food for allThe disparity between haves and have-nots widens Then, its civilization collapses

Other civilizations collapsed when they failed to recognize the constraints of their environment

Mayans, Greeks, Incas, and Romans The future is uncertain for Easter Island

Much depends on the efforts of the Rapa Nui8

Wednesday, January 11, 2012

Have ‘we’ learned anything? The state of the planet

The world faces four unhealthy global trends:

(1) Increasing population growth and its detrimental effects on human well-being

(2) A decline of vital ecosystem services(3) The negative impacts of global climate

change(4) A loss of biodiversity


Increasing populations decrease human well-being

Today, there are more than 6.8 billion persons The population grew by 2 billion in the last 25 years 75 million persons are added each yearBy 2050, there could be 9.1 billion peopleThey will have to be fed, clothed, housed, and have jobs

Most population increases will be in developing countries

985 million experience extreme poverty ($1 a day)Over 800 million are malnourished 6 million preschoolers die each year of hunger and malnutrition


The world’s population has exploded


Global economic productionHas doubled since 1986

Average gross domestic product (GDP) in low-income countries has improved

But real income in most developing countries is falling

Because of the large inequalities in wealth between them and developed countriesStabilizing population growth in developing countries is also essential for closing this economic gap


The decline of ecosystems Ecosystems support human life and economies with goods and servicesThese vital resources are not being managed well

Humans are depleting groundwater, degrading soils, overfishing, and depleting forests

The world economy depends on renewable resources For fresh water, food, fuel, wood, leather, furs, etc.For raw materials for fabrics, oils and alcohols, etc.

Agriculture, forestry, and fishing are responsible for 50% of all jobs worldwide


Ecosystems provide services They support human life and economic well-being

Waste breakdown, climate regulation, erosion control, pest management, maintenance of nutrient cycles

These goods and services are “ecosystem capital”Human well-being and economic development depend on the products of this capital—its income

Goods and services are provided as long as the ecosystems producing them are protected Ecosystem capital in a nation and its income-generating capacity represent a major form of a nation’s wealth


However, global research projects have shown that . . .

Humans have altered the world’s ecosystems more rapidly and profoundly over the past 50 years than at any time in human history

Over 60% of ecosystem goods and services are being degraded or used unsustainably If this is not reversed, there will soon be deadly consequences

Thess projects builds a knowledge base for sound policy decisions and management

Policy makers and managers must act on that knowledge


Global climate change: a serious problem

Global climate change is a serious problem now!Due to the accumulation of greenhouse gases Carbon dioxide is a by-product of burning fossil fuels

Carbon dioxide is a natural component of the atmosphere

It is required by plants for photosynthesis It’s important to the Earth’s atmosphere energy system

The greenhouse effect: carbon dioxide absorbs infrared (heat) energy radiated from Earth’s surface, which warms the lower atmosphere


Global temperature and carbon dioxide


Another global study . . .Established by the United Nations in 1988 Reports its assessment of climate change every 5 years The Fourth Assessment Report (FAR) (2007)

Input from thousands of scientific experts and hundreds of authorsThis assessment produced convincing evidence that human-induced climate change is already severely impacting global climate and sea levelConcluded that future changes could be catastrophic if emissions of greenhouse gases are not controlled


The Kyoto Protocol: reducing greenhouse gas emissions166 nations met in Kyoto, Japan, in December 1997

Most industrialized nations agreed to reduce emissions

Ratified in 2005, it is in force in most industrialized nations

However, the United States, the biggest emitter, withdrew in 2001!

Kyoto is only a first step Levels of greenhouse gases will continue to riseShort-term economic impacts conflict with the long-term consequences of climate change

Climate change is one of the defining environmental issues of the 21st century


Loss of biodiversity Biodiversity: variability among living organisms and the ecological complexes of which they are part Causes of biodiversity losses

Conversion of landPollutionExploitation for commercial valueSpecies are hunted, killed, and marketed illegally

Species are declining in their range and/or population size

Of 5–30 (100+) million species, 2 million have been describedVertebrate species have declined by 27% since 1970 20


Biodiversity loss is crucialWe threaten our well-being when we diminish biodiversity It is the mainstay of agricultural crops and medicines

Losses will curtail development in these areasIt helps maintain natural systems

Enabling them to recover after a disturbanceIt provides essential goods and services

Particularly for the poorAesthetic and moral arguments for biodiversity

Do we have a moral responsibility to protect and preserve the amazing diversity of life on Earth?


Environmental scienceHuman societies live in the natural world

We use materials, converting parts of it into the built environment (towns, factories, highways)We change natural ecosystems into agricultural onesWe use the environment to dump wastes

The environment: is an inclusive conceptIt includes the natural worldHuman societies and the human-built world


Human successes and failuresHumans have achieved great successes

Domesticated landscapes to produce food for billionsConverted natural materials into goods and servicesTapped carbon-based fuels for electricity, heat, power, manufacturing

Success carries dangers, tooAir pollution and increased atmospheric temperatureEnvironmental contaminationOverharvested forests and fisheries


So . . .Environmental science: the study of how the world works—all about interactions

Examines cause-and-effect relationships underlying issues and problems that rise from our (human) use of the natural world

It provides answers that allow societies to make changes consistent with a sustainable futureEncompasses many disciplines

History, engineering, geology, physics, medicine, biology, sociology

It is the most multidisciplinary of all sciences24


The early environmental movement

Has its roots in the late 19th centuryUnique, wild aspects of the U.S. were disappearing

In 1890, the frontier was closedNo part of the country was totally uninhabited

Conservation groups were formedNational Audubon Society, National Wildlife Federation, Sierra Club

President Theodore Roosevelt placed 230 million acres under public protectionA national environmental consciousness was stirring 25


Farming and drought produced the Dust Bowl


The Great Depression and World War II had an influence

During the Great Depression, conservation provided environmental protection and jobs

The Civilian Conservation Corps (CCC) built trails, planted trees, and improved national parks and forests

The years after World War II brought technological optimism

Tremendous production capacity and new technology were redirected to peacetime applications

Environmental problems became obviousPolluted air, fouled rivers and beaches, species declines


The modern environmental movement

Rachel Carson wrote Silent Spring (1962)She described a future with no songbirds, along with other consequences of pesticide pollution

The modern environmental movement: a newly militant citizenry demanded

Curtailment of pollutionCleanup of polluted areasProtection of pristine areas

It began as a grassroots initiativeContinues to command public interest and support


EnvironmentalismWildlife advocates became active in the environmental movement

Environmental Defense Fund, Natural Resources Defense Council, Greenpeace, Union of Concerned Scientists

Environmentalists: persons and organizations with a strong focus on environmental concernsEnvironmentalism: the widespread development of the environmental movement


The environmental movement has been successful

Congress created the Environmental Protection Agency (EPA) in 1970Congress passed laws for pollution control and wildlife protection Society has spent billions of dollars in pollution control Governments have spent billions upgrading sewage treatment and refuse disposal systemsThe air and water are much cleaner than in the 1960s

Without the environmental movement, our air and water would be a toxic brew


Environmentalism has criticsEarly in the environmental movement

It was easy to identify specific sources of problemsSolutions seemed straightforward

But polluting industries demanded deregulationThey believed regulations harmed the economyThey found allies in Congress and in some presidents

Political battles surround almost every environmental issue

Bitter conflicts arise over publicly owned resourcesSpecial interests oppose regulationsPolitics always accompanies policy


Moving toward sustainabilityTo move toward sustainability we need:

Sound science: understanding how the world works and how humans interact with itSustainability: the goal we should be working towardStewardship: managing natural resources and human well-being for the common good


Three unifying themes for sustainability


Sound science: the scientific methodMany environmental issues are so controversial, people are left confusedThe scientific method: a way of gaining knowledge

Science: all the knowledge gained through this methodIs legitimate, in contrast with junk science: information that is presented as science but is not

Junk science does not conform to the rigorous methods and practices of legitimate scienceSound science involves using the scientific method to understand how the natural world works 34


Four assumptions of the scientific method:

What we perceive with our senses represents objective realityObjective reality functions according to certain basic, consistent principles and natural lawsEvery result has a cause

Every event in turn will cause other eventsEvents do not occur without reason

Through observation, manipulation, and reason, we can discover and understand natural laws by which the universe functions


The scientific methodThe scientific method consists of observation, hypothesis, test (experiment), explanationObservation: seeing, hearing, smelling, etc.

Can lead to explanations of some natural phenomenaThe basis for natural history, astronomy, anthropology, evolutionary biologyIs involved in zoology, botany, geology, comparative anatomy, and taxonomy

Careful observation is the keystone of scienceHelps model how the world works


An interplay . . .


Not every observation is accurateThis can be due to honest misperceptions or even calculated mischiefBe skeptical of any new report until it is confirmed

This involves further investigationAs observations are confirmed, they gain the status of factual dataFacts: things or events that have been confirmed by more than one observer

Remain open to being reconfirmedThings that cannot be confirmed (e.g., UFOs) belong in the realm of speculation


ExperimentationSets up situations to make systematic observations regarding causes and effectsFor example, the atomic theory is a cause-and-effect picture that measures how chemicals reactSimilarly, by putting plants and animals into specific situations, responses can be observed and measuredIs limited to things that can be manipulated

Not good for things that happened in the past (but computer simulations . . . )


40

An experiment shows the

importance of mycorrhizae


Experimentation is usually systematic

Careful accounts are usually kept to have an accurate record of causes and effectsFor example, to discover why Indian vultures declined:

Hypotheses (educated guesses) were made about the cause of the declineEach hypothesis was tested through observation or experimentationExperimental results showed that a veterinary drug used in livestock killed vultures when they ate carcasses


TheoriesHypotheses tentatively explain how observations are relatedHypotheses become theory only after much testing and confirmation

A theory is logically consistent with all observations

Theories can suggest or predict certain eventsPredictions require more experiments, observations, etc.

A theory represents a valid interpretation of realityWhen it provides a logically consistent framework for all relevant observations (facts) When it can be used to reliably predict outcomes


Is one theory as good as another?Some people argue that a theory is not proven fact

So all theories are equalBut one theory may have overwhelming supporting evidence that contradicts other theoriesTo evaluate a theory

Ask about its supporting evidenceDoes another theory have more or less evidence?


Natural lawsThe second assumption underlying science: the universe functions according to certain basic principles

Cannot be proved with absolute certaintyBut every observation and test have borne it out

Natural laws: principles by which we can define and predict the behavior of matter and energy

Laws of Gravity, Conservation of Matter, Thermodynamics

The mathematical language of probability and statistics can express theories

Predator-prey relationships, effects of pesticides44


Concepts in the natural worldExplanations of data gathered from the natural world

Can be predictiveBut never reach the status of laws

They model the way we think the natural world works and . . .

Let us make qualified predictions of future outcomes

For example, based on our understanding of the pesticide DDT and that mosquitoes can become resistant to DDT, we predict that spraying a marsh with DDT is likely to result in resistant mosquitoesA concept can be used to modify public policy


The role of instruments in scienceComplex instrumentation: another hallmark of scienceScientific instruments

Extend our powers of observation (telescopes, microscopes, X-ray machines, CAT scans)Are used to quantify observationsAllow us to make observations or conduct experiments

Instruments must be properly calibrated to avoid mistakes


The scientific community: peer reviewTheories are always less than absolutely certain

Some other theory may better explain the dataOur confidence in scientific knowledge should be proportional to the evidence supporting it

There is no single authoritative source that judges the validity of scientific theories

A collective body of competent, experienced scientists establishes what is competent and what is not

Scientific experts analyze their colleagues’ work 47


Why controversies exist in scienceNew information arises from new observations

It takes time for hypotheses to be testedFurther observation and testing settle the question

Complex phenomena are not easily testedHard to say which hypothesis is correctScientists eventually reach a consensus

Bias by those who stand to profit from controversyThey harp on disagreements and downplay evidence

Subjective values: different people have different feelings

E.g., about the human response to environmental issues


Junk scienceThe media and public often give equal credibility to opposing views on an issue (e.g., global warming)Junk science: information presented as scientifically valid but that does not conform to the rigors of true scienceAntienvironmental special interests refer to junk science as anything that threatens their preferred viewpointTrue junk science takes many forms:

Picking and choosing only results supporting your ideaPolitically motivated distortions of informationPublication of results in unreviewed books or journals


Use the scientific method to judge viewpoints

What observations underlie explanations?Do explanations and theory logically follow the data?Does the explanation account for all observations?Are there reasons an explanation is favored? Who profits?Do scientific experts support the conclusion?Sound science is essential to forging a sustainable relationship with the natural world

Information must be accurate, credible, and communicated clearly to policy makers and the public 50


SustainabilityA system is sustainable if it can continue indefinitely without depleting material or energy resourcesFirst applied to sustainable yields in forestry and fisheries

Harvest resources but stay within the capacity of the population to grow and replace itselfAlso applies to fresh water, soils, pollution absorption

Sustainable ecosystems: entire natural systems that Thrive over time by recycling nutrients, maintaining a diversity of speciesUse the Sun as a source of energy


Sustainable societiesA sustainable society is in balance with the natural world

Continues for generationsDoes not deplete its resource baseDoes not produce more pollution than nature can absorb

Many of our interactions with nature are not sustainable

Declining biodiversity and ecosystemsGreenhouse gasesPopulation growth in developing countriesEnergy and resource consumption in developed countries


Sustainable developmentDefined by the World Commission on Environment and Development and published in Our Common Future (1987)Sustainable development: development or progress that meets the needs of the present without compromising the ability of future generations to meet their needsDevelopment: improvement of human well-beingDeveloped countries are concerned with environmental sustainability

Developing countries are concerned with economic development


The concept of sustainable developmentIncorporates equity: meeting the needs of the present

But future generations are seen as equally deserving

Sustainability means different things to different people

Economists are concerned with growth, efficiency, resource useSociologists focus on human needs (equity, empowerment, social cohesion, cultural identity)Ecologists want to preserve the integrity of natural systems, live within the carrying capacity of the Earth, and deal with pollutants


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Achieving sustainable solutions


An essential transition to sustainability

It is hard to picture the transition to a sustainable society

A stable human population must recognize the finite limits of Earth’s ability to provide resources and absorb wastes

If we don’t achieve sustainability, nature will do it for usRequires dedication to care for the natural world

Requires acting with justice and equity toward one another


Transitioning to sustainability needs:

A demographic transition from an increasing human population to a stable oneA resource transition from a growth-obsessed economy to one that protects nature’s income and ecosystemsA technology transition from pollution-intensive technologies to environmentally friendly onesA political/sociological transition that embraces a stewardly and just approach that eliminates much povertyA community transition from car-dominated urban sprawl to smaller, more livable cities


Stewardship: the third unifying themeActions and programs that manage natural resources and human well-being for the common goodStewards care for something they do not own

The natural world or human cultureThey will pass it on to the next generation

Environmental stewardshipGuides actions benefiting the natural world and peopleRecognizes that land ownership is temporary

Stewardship deals with how to achieve sustainabilityActions to take and values and ethical considerations


Who are the stewards?People who try to stop environmental destruction and pollutionRachel Carson, who wrote Silent Spring (1962)Pablo F. Mendoza and Luis Yanza of Ecuador, who demanded that Chevron pay for its petroleum contamination

Ecuador passed stronger environmental lawsThey won the 2008 Goldman Prize

Dr. Wangari Maathai of Kenya, who founded the Green Belt Movement

The first Kenyan woman to earn a Ph.D.Beaten and jailed for protesting government corruption


Stewardship involves everyday people

They care for each other and the natural worldThey recycle, buy less-polluting cars, turn off lights in empty rooms, use less energy, don’t engage in conspicuous consumptionThey support environmental organizationsThey stay informedThey vote for political candidates sympathetic to the environmental movement and sustainable development


Justice and equityStewardship is also concerned with just relationships between humansThe environmental justice movement in the U.S.

Addresses environmental racism: the placement of waste sites and other harmful industries in areas containing nonwhite residentsWealthier, politically active white communities get more facility improvements (roads, public buildings, water and sewer projects)


People are correcting injustices

People create citizen groups and watchdog agenciesTo bring effective actionTo monitor progress

E.g. Two areas in Tennessee have 42 hazardous waste sites

12 are seriously polluted Superfund sites requiring government intervention and remediationCancer and asthma rates are very highPeople organized Stop Toxic Pollution (STOP) to draw attention to the waste and obtain money to fence off the sites


Justice for the developing worldJustice is crucial for the developing world

People lose their land, have inadequate food, and are in poor health

Extreme poverty for a billion people results from injustice

Wealthy, politically powerful people steal money Corporations receive preferential treatment

Government reform is needed so the poor receive justice

Gain land and access to ecosystem goods and services


Wealthy nations contribute to injustice

Wealthy industrialized countries help cause poverty in developing countriesInternational trade discriminates against developing countries

Industrialized countries tax and restrict imports from developing countriesThey flood world markets with products priced below real costsSuch barriers deprive people of jobs and money


Moving toward a sustainable future

Globalization: the accelerating interconnectedness of human activities, ideas, and cultures

Its consequences will be profound for economies, cultural patterns, political arrangements, environmental resources, and pollution

Globalization has improved well-being and healthIn markets, information, research

But it has also diluted and destroyed cultural and religious ideals and has done little to improve economic well-being


Effects of globalization: economic changes

Globalization has economically reorganized the worldIt has facilitated communication through the Internet, satellites, and cablesIt has eased transportation and financial transactionsTransnational corporations have huge wealth and powerSpecial trade arrangements between countries give preferential treatment to some and deny trade access to othersIt markets Western diets, styles, and culture to the world

Local customs and diversity suffer66


Effects of globalization: environmental changes

Dissemination of information allows organizations and agencies to connect with the public

People have become politically involvedConsumers can find environmentally friendly products However, it has had extremely harmful outcomes, too

SARS virus and the H1N1 avian influenzaDispersion of exotic speciesHazardous wastes, pollution, nuclear radiation falloutDestruction of the ozone layer Climate change


A new commitmentPeople everywhere recognize that “business as usual” is not sustainable

Global trends are on a collision course with the planet’s systems that maintain life

Current trends will lead to a point where resources can’t support humans

Civil order will break downGood news is available, too

Fewer people are starvingLife expectancy is risingPopulation growth rates are slowing


People are pressuring for change Environmental awareness in industrialized countries led to establishment of policies, laws, and treaties to protect resources and reduce pollutionPeople are changing direction

Wind energy for electricityCap-and-trade markets to curb greenhouse emissions$100 billion/year is addressed to environmental concerns

Environmental degradation can be slowedPeople can be freed from hunger and povertyPeople can change from exploiting to conserving Earth


So there is hope . . .And over the next several weeks we’ll investigate how this science is done,What we have discovered,The public interactions with it,And how we can help.


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