Presentation on theme: "Environment: The Science behind the Stories"— Presentation transcript:
1Environment: The Science behind the Stories Lecture OutlinesChapter 1Environment: The Science behind the Stories4th EditionWithgott/Brennan
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
3Our island: Earth Earth may seem enormous But it and its systems are finite and limitedWe can change the Earth and damage its systemsEnvironment: all the living and non-living things around usAnimals, plants, forests, farms, etc.Continents, oceans, clouds, ice capsStructures, urban centers, living spacesSocial relationships and institutions
4Humans and the world around us Humans change the environment, often in ways not fully understoodWe depend completely on the environment for survivalIncreased wealth, health, mobility, leisure timeBut, natural systems have been degradedi.e., pollution, erosion and species extinctionEnvironmental changes threaten long-term health and survivalEnvironmental science is the study of:How the natural world worksHow the environment affects humans and vice versa
5Natural resources: vital to human survival Natural resources = substances and energy sources needed for survivalRenewable resources:Perpetually available:sunlight, wind, wave energyRenew themselves over short periods:timber, water, soil(some can be destroyed)Nonrenewable resources: can be depleted – take millions of years to replenishOil, coal, minerals
6Global human population growth More than 7 billion humans on Earth todayWhy so many humans?Agricultural revolutionStable food suppliesIndustrial revolutionUrbanized society powered by fossil fuelsSanitation and medicinesMore food
7Population & 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 dayOur consumption of resources has risen even faster than our population growth.Life has become more pleasant for us so farHowever, rising consumption amplifies the demands we make on our environment.
8Garrett Hardin’s Tragedy of the Commons Unregulated exploitation leads to resource depletionSoil, air, waterCompetition increases use until the resource is goneSolutionsPrivate ownership?Voluntary organization to enforce responsible use?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 capacityWe are using 30% more of the planet’s resources than are available on a sustainable basis!
10Ecological 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
11Environmental science … can help us avoid 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?
12Environmental science: how does the natural world work? impacts It has an applied goal: developing solutions to environmental problemsAn interdisciplinary fieldNatural sciences: information about the worldEnvironmental Science programsSocial sciences: values and human behaviorEnvironmental Studies programsEnvironmentHumans
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
14Theories and paradigm shifts Theory: a well-tested and widely accepted explanationConsolidates widely-supported, related hypothesesParadigm shift – a dramatic upheaval in thoughtIt changes the dominant viewpointWicked problems: are complex, with no simple solutionI.e. environmental problems
15What is an “environmental problem”? The perception of what constitutes a problem varies between individuals and societiesEx.: DDT, a pesticideIn developing countries: welcome because it kills malaria-carrying mosquitoesIn developed countries: not welcome, due to health risks
16We face challenges in agriculture Expanded food production led to increased population and consumptionIt’s one of humanity’s greatest achievements, but at an enormous environmental costNearly half of the planet’s land surface is used for agricultureChemical fertilizersPesticidesErosionChanged natural systems
17We face challenges in pollution Waste products and artificial chemicals used in farms, industries, and householdsEach year, millions of people die from pollution
18We face challenges in climate Scientists have firmly concluded that humans are changing the composition of the atmosphereThe Earth’s surface is warmingMelting glaciersRising sea levelsImpacted wildlife and cropsIncreasingly destructive weatherSince the Industrial Revolution, atmospheric carbon dioxide concentrations have risen by 37%, to the highest level in 650,000 years
19We face challenges in biodiversity Human actions have driven many species extinct, and biodiversity is declining dramaticallyWe 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
20The Millennium Ecosystem Assessment The most comprehensive scientific assessment of the condition of the world’s ecological systemsMajor findings:Humans have drastically altered ecosystemsThese changes have contributed to human well-being and economic development, but at a costEnvironmental degradation could get much worseDegradation can be reversed, but it requires work
21Our energy choices will affect our future The lives we live today depend on fossil fuelsMachinesChemicalsTransportationProductsFossil fuels are limited; supplies will certainly decline, and they are becoming harder to find.We have used up ½ of the world’s oil supplies; how will we handle this imminent fossil fuel shortage?
22Sustainability and the future of our world Sustainability: we must live within our planet’s meansSo the Earth and its resources can sustain us and all life for the futureSustainability involves conserving resourcesDeveloping long-term solutionsKeeping fully functioning ecosystemsNatural capital: Earth’s total wealth of resourcesWe are withdrawing it faster that it’s being replenishedWe must live off Earth’s natural interest (replenishable resources), not its natural capital
23Sustainable solutions exist We must develop solutions that protect both our quality of life and the environmentOrganic agricultureTechnologyReduces pollutionBiodiversityProtect speciesWaste disposalRecyclingAlternative fuels
24Sustainable development Involves environmental protection, economic well-being and social equityThe poor suffer the most from environmental degradationDevelopment: purposeful changes to improve the quality of lifeSustainable development: resources satisfy current needs without compromising future availability of resourcesIt is not ever increasing economic gainIt values and prioritizes environmental protectionHuman-made capital cannot substitute for natural capital
25Will 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
26ConclusionEnvironmental 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