Presentation on theme: "Ch 1 An Introduction to Environmental Science"— Presentation transcript:
1Ch 1 An Introduction to Environmental Science Part 1: Foundations of Environmental Science
2This lecture will help you understand: The meaning of the term environmentThe importance of natural resourcesThat environmental science is interdisciplinaryThe scientific method and how science operatesSome pressures facing the global environmentSustainability and sustainable development
3Environment: the total of our surroundings All the things around us with which we interactBIOTIC FACTORS Living things(Animals, plants, forests, fungi, etc.)ABIOTIC FACTORS Nonliving things(Continents, oceans, clouds, soil, rocks)Our built environmentBuildings, human-created living areasSocial relationships and institutions
4Humans and the world around us HUMANS change the environment, often in ways notfully understoodWe depend on the environment for survivalIncreased wealth, health, mobility, leisureBut, natural systems have been degradedi.e., pollution, erosion and species extinctionEnvironmental changes threaten health and survivalEnvironmental science is the study of:1) How the natural world works2) How the environment affects humans and vice versa
5Natural resources: vital to human survival Substances and energy sources needed for survivalRenewable ResourcesPerpetually available (Ex: sunlight, wind, wave energy)Renew themselves over short periods: timber, water, soil (these can be destroyed)Nonrenewable Resources can be depletedEx: Oil, coal, minerals
6Global human population growth More than 6.7 billion humansWhy so many humans?1) Agricultural revolutionStable food supplies2) Industrial revolutionUrbanized society powered by fossil fuels(Sanitation, medicines, and more food)
7Thomas Malthus and human population Population growth must be restricted, or it will outstrip food production(Starvation, war, disease)NEO-MALTHUSIANSPopulation growth has disastrous effectsPaul and Anne Ehrlich, The Population Bomb (1968)
8Garrett Hardin’s “Tragedy of the Commons” Unregulated exploitation leads to resource depletionResource users are tempted to increase use until the resource is goneWhat is a viable solution?Private ownership?Voluntary organization?Governmental regulations?
9The “Ecological Footprint” The environmental impact of a person or populationAmount of biologically productive land + waterfor raw materials and to dispose/recycle wasteOVERSHOOT: humans have surpassed the Earth’s capacity to sustain usWe are using 30% more of the planet’s resources than are available on a sustainable basis!
10Lesson of Easter Island … can help us avoid mistakes made by past civilizationsThe lesson of Easter Island: people annihilated their culture by destroying their environment. Can we act more wisely to conserve our resources?
11How does the natural world work? Environment Impacts HumansIt has an applied goal: developing solutions to environmental problemsAn interdisciplinary fieldNatural sciences: information about the worldEnvironmental Science programsSocial sciences: values and human behaviorEnvironmental Studies programs
12What is an “environmental problem”? Any undesirable change in the environmentThe perception of what constitutes a problem varies between individuals and societies (different situations)Ex: DDT, a pesticideIn developing countries: welcome because it kills malaria-carrying mosquitoesIn developed countries: not welcome, due to health risks
13Environmental science is NOT environmentalism The pursuit of knowledge about the natural worldScientists try to remain objectiveENVIRONMENTALISMA social movement dedicated to protecting the natural world
14The nature of science Science: A systematic process for learning about the world and testing our understanding of itA dynamic process of observation, testing, and discoveryThe accumulated body of knowledge that results from this processScience is essentialTo sort fact from fictionDevelop solutions to the problems we face
15Applications of science Policy decisions and management practicesTechnologyEnergy-efficient methanol-powered fuel cell car from DaimlerChryslerRestoration of forest ecosystems altered by human suppression of fire
16The scientific method A technique for testing ideas with observations Assumptions:The universe works according to unchanging natural lawsEvents arise from causes, and cause other eventsWe use our senses and reason to understand nature’s laws
17The scientific methodA scientist makes an observation and asks questions of some phenomenonThe scientist formulates a hypothesis, a statement that attempts to explain the scientific question.The hypothesis is used to generate predictions, which are specific statements that can be directly and unequivocally tested.The test results either support or reject the hypothesis
18Experiments test the validity of a hypothesis Natural or correlational tests show real-world complexity(Results are not so neat and clean, so answers aren’t simply black and white)Manipulative experiments yield the strongest evidence(But, lots of things can’t be manipulated)
19The scientific process is part of a larger process The scientific process includes peer review, publication, and debateA consistently supported hypothesis becomes a theory, a well-tested and widely accepted explanationWith enough data, a paradigm shift – a change in the dominant view – can occurSTRENGTH: Science will change if evidence is there!!
20Population & consumption Human population growth exacerbates all environmental problemsThe growth rate has slowed, but we still add more than 200,000 people to the planet each day!Our consumption of resources has risen even faster than our population growth.Life has become more pleasant for us so far…However, rising consumption amplifies the demands we make on our environment!!
21Ecological footprints are not all equal The ecological footprints of countries vary greatlyThe U.S. footprint is almost 5 times greater than the world’s averageDeveloping countries have much smaller footprints than developed countries
22We face challenges in agriculture Expanded food production led to increased population and consumption (New technology)It’s one of humanity’s greatest achievements, but at an enormous environmental cost(Nearly half of the planet’s land surface is used for agriculture)- Chemical fertilizers- Pesticides- Erosion- Changed natural systems
23We face challenges in pollution Waste products and artificial chemicals used in farms, industries, and householdsEach year, millions of people die from pollution!!
24We face challenges in climate Scientists have firmly concluded that HUMANS are changing the composition of the atmosphereThe Earth’s surface is warming- Melting glaciers- Rising sea levels- Impacted wildlife and crops- Increasingly destructive weatherSince the Industrial Revolution, atmospheric carbon dioxide concentrations have risen by 37%, to the highest level in 650,000 years!!!
25We face challenges in biodiversity Human actions have driven many species extinct, and biodiversity is declining dramatically- We are at the onset of a mass extinction eventBiodiversity loss may be our biggest environmental problem; once a species is extinct, it is gone forever!
26The Millennium Ecosystem Assessment The most comprehensive scientific assessment of the condition of the world’s ecological systemsMajor findings:1) Humans have drastically altered ecosystems2) These changes have contributed to human well-being and economic development, but at a cost3) Environmental degradation could get much worse4) Degradation can be reversed, but it requires work
27Our energy choices will affect our future The lives we live today are due to fossil fuels- Machines- Chemicals- Transportation- ProductsFossil fuels are a one-time bonanza; supplies will certainly declineWe have used up ½ of the world’s oil supplies; how will we handle this imminent fossil fuel shortage?
28Sustainable solutions exist We must develop solutions that protect both our quality of life and the environmentOrganic agricultureTechnologyReduces pollutionBiodiversityProtect speciesWaste disposalRecyclingAlternative fuels
29Are things getting better or worse? Many people think environmental conditions are betterCornucopians: Human ingenuity will solve any problemSome think things are much worse in the worldCassandras: predict doom and disasterHow can you decide who is correct?Are the impacts limited to humans, or are other organisms or systems involved?Are the proponents thinking in the long or short term?Are they considering all costs and benefits?
30Sustainability: a goal for the future How can humans live within the planet’s means?Humans cannot exist without functioning natural systemsSustainabilityLeaves future generations with a rich and full EarthConserves the Earth’s natural resourcesMaintains fully functioning ecological systemsSustainable development: the use of resources to satisfy current needs without compromising future availability of resources
31Will we develop in a sustainable way? The triple bottom line: sustainable solutions that meetEnvironmental goalsEconomic goalsSocial goalsRequires that humans apply knowledge from the sciences toLimit environmental impactsMaintain functioning ecological systems
32ConclusionEnvironmental science helps us understand our relationship with the environment and informs our attempts to solve and prevent problems.Identifying a problem is the first step in solving itSolving environmental problems can move us towards health, longevity, peace and prosperityEnvironmental science can help us find balanced solutions to environmental problems
33QUESTION: Review The term “environment” includes Animals and plants Oceans and riversSoil and atmosphereAll of the above are included in this termAnswer: d
34QUESTION: ReviewWhich of the following is correct about the term “environmentalism”?It is very science-orientedIt is a social movement to protect the environmentIt usually does not include advocacy for the environmentIt involves scientists trying to solve environmental problemsAnswer: b
35QUESTION: ReviewAdding various amounts of fertilizer to plants in a laboratory is a _____ type of experimentCorrelativeNaturalManipulativeRareAnswer: c
36QUESTION: Review What is the definition of “sustainable development”? Using resources to benefit future generations, even if it means lower availability nowLetting future generations figure out their own problemsUsing resources to satisfy current needs without compromising future availabilityLetting each country decide what is its best interestAnswer: c
37QUESTION: Weighing the Issues Which do you think is the best way to protect commonly owned resources (i.e., air, water, fisheries)?Sell the resource to a private entityVoluntary organizations to enforce responsible useGovernmental regulationsDo nothing and see what happensAnswer: any
38QUESTION: Weighing the Issues Do you think the rest of the world can have an ecological footprint as large as the footprint of the United States?Yes, because we will find new technologies and resourcesYes, because the footprint of the United States is not really that largeDefinitely not; the world does not have that many resourcesIt does not matter; it’s not that importantAnswer: any
39QUESTION: Interpreting Graphs and Data According to this graph, what has happened to the population over the last 500 years?a) It has grown exponentiallyb) It has grown linearlyc) It has decreasedd) It has slowed down recentlyAnswer: a
40QUESTION: Interpreting Graphs and Data What happens if test results reject a hypothesis?The scientist formulates a new hypothesisIt shows the test failedThe hypothesis was supportedThe predictions may not have been correctAnswer: a