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Introduction to Environmental Sciences: An Introduction
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Introduction to Environmental Sciences:
1. An Introduction
Earth 122Prof. Walter A. Illman
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Introduction to Environmental Sciences
LECTURER: Prof. Walter A. IllmanOffice – 229C Physics
Office hours: 10:00 – 11:00 am, F or by appointment
Phone: ext. 38341e‐mail: [email protected]
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Introduction to Environmental SciencesClass Time: M, W, F; 11:30 am – 12:20pmCredit: 0.5 units
REQUIRED TEXTS/Materials (Available at Campus Bookstore):
• Environment: The Science Behind the Stories, 2nd Canadian ed.– Withgott et al. 2012– Pearson Canada
• Introduction to Environmental Science Lecture Notes Winter 2013. Illman
• Available on UW‐Learn Earth 122 course website
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Introduction to Environmental Sciences
• ATTENDANCE IS REQUIRED• 3 EXAMS 50 min.• IN CLASS
1. Jan 25, 20132. Feb 15, 20133. Mar 15, 2013
FINAL EXAM ~ 50% CUMULATIVEEarly‐mid‐April (to be announced)
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GRADE BREAKDOWN
• 10 Quizzes (unannounced) 100• 3 EXAMS 300• 1 FINAL 200• TOTAL 600
• Exams have to be taken on the scheduled dates. However, under certain circumstances (illness, etc.) with proper documentation, make‐up exams could be given by TAs. Talk to TA.
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Teaching Assistants
HEAD TEACHING ASSISTANT (TA): Jerry Hu; Office – PHY 2022;
Office hours: TBD or by appointmente‐mail: [email protected]
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Teaching AssistantsLecture portion TA• Jerry Hu ([email protected])
Questions on course materials (Earth 122), add/drop forms, rescheduling of exams
Laboratory portion (Earth 122L) TAs• Fatemeh Vakili ([email protected])• William Sellier ([email protected])• Amanda Niederkorn ([email protected])
Questions on laboratory portion, add/drop forms
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Lab portion‐announcements
• No labs first week!!!• If you are registered in Earth 122L, lab attendance is mandatory ~ no makeups unless there is an emergency or illness (documentation required).– Work out with TA
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How to “A”ce this Class• Read assigned chapter before coming to class• Come to class• Pay attention! Take notes! Focus on emphasized subjects. Read assigned chapter again emphasizing material covered in lecture
• Be sure to review definitions in each chapter• Don’t procrastinate (keep up with material)
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Basic Rules and ConsiderationsTalking is disruptive to your classmates and your
professor!!
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This lecture will help you understand:• The meaning of the term
environment• The importance of natural
resources• That environmental science is
interdisciplinary • The scientific method and how
science operates• Some pressures facing the
global environment• Articulate concepts of
sustainability and sustainable development
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Central Case: Earth from Space: The Power of an Image
• Prior to 1967, no one had seen a photograph of the whole planet
• On Novemeber 9, 1967 ‐ a simple photograph from the unmanned Apollo 4, showing “cresent” Earth changed both society and history
• Earth rise ‐ taken hand‐held by Apollo 8 astronaut James Lovell, December 24, 1968
• Apollo 17, 1972 ‐ famous Blue Marble image credited with kick‐starting the modern environmental movement
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Our Island, Earth
• Environment: All the things around us with which we interact:• Biotic (living things)
• Animals, plants, forests, soils, etc.
• Abiotic (nonliving things)• Continents, oceans, clouds, icecaps
• Our built environment• Structures, human‐created living centers
• Social relationships and institutions
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Environmental science explores interactions between humans & the physical + biological world
• Humans are altering the natural systems we need• Enrichment:
– Health, lifespan, wealth, mobility, leisure• Impacts:
– Natural systems have been degraded – Long‐term threat on health and survival
• Environmental science is the study of:– How the natural world works– How the environment affects humans and vice versa– Such knowledge is essential in devising solutions to environmental problems
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Natural resources: vital to human survival
• Renewable resources:– Perpetually available: sunlight, wind, wave energy– Renew themselves over short periods: timber, water, soil
• can be overharvested and can become nonrenewable• Nonrenewable resources: finite supply; can be depleted
– Oil, coal, minerals
Natural resources = various substances and energy sources needed for survival
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Natural resources: vital to human survival
• Resource management:- Balancing the use of a resource with its protection and preservation
- The stock is the harvestable portion of the resource
http://en.wikipedia.org/wiki/File:Sardines_-_%E9%B0%AF(%E3%81%84%E3%82%8F%E3%81%97).jpg
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Global human population growth
• More than 7 billion humans (late 2011); Why so many humans?– Old Stone Age (~2.5Mya)
• Fire and tools
– Agricultural revolution (~10Kya)• Stable food supplies
– Industrial revolution (mid‐1700s)• Urbanized society powered by fossil fuels
• Sanitation and medicines• More food
– Medical‐technological revolution (now)
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Resource consumption exerts social and environmental impacts
• Total impact (I) on the environment as the product of population (P), affluence (A), and technology (T):
• Impacts of population increase;• Impacts of increased consumption of natural resources (i.e., affluence); and
• Impacts of new technology on the environment.
I P A T
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Carrying Capacity• Carrying capacity: it is a measure of the ability of a system to support life. – The number of individuals of a particular species that can be sustained by the biologicial productivity of a given area of land
• Expressed as number of individuals of particular species that can be sustained by the biological productivity of a given area of land.
• Exceeding the carrying capacity:– Population decline or collapse– System will be altered, damaged, or depleted
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The Tragedy of the Commons• Unregulated exploitation leads to resource depletion• Resource users are tempted to increase use until the resource is gone• Solution?
• Private ownership?• Voluntary organization to enforce responsible use?
• Governmental regulations?
http://en.wikipedia.org/wiki/Tragedy_of_the_commons
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Resource consumption exerts social and environmental impacts • Calculating our ecological footprint:
– The environmental impact of an individual or population
– Amount of biologically productive land + water required to provide raw materials a population consumes and absorb the waste produced
• Overshoot: humans have surpassed the Earth’s capacity
We are using 39% more of the planet’s resources than are available on a sustainable basis from all the land!
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Environmental science… can help us avoid mistakes made in the past.
The lesson of Easter Island: people annihilated their culture by destroying their environment. Can we act more wisely to conserve our resources?
22http://en.wikipedia.org/wiki/Easter_Island
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Environmental science is interdisciplinary
• Environmental problems is a complex endeavour that requires expertise from many disciplines
• Environmental science is thus an interdisciplinary field
• An integrated approach to addressing problems can produce effective and lasting solutions
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Environmental science is interdisciplinary
• What experts would you need for:–The construction of a new hydroelectric dam?
–The proposed draining of a wetland to build a new subdivision?
–A proposal to permit bear hunting in a national park
–The management of a large oil spill offshore from a pristine beach?
http://en.wikipedia.org/wiki/Deepwater_Horizon_oil_spill
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What is an “environmental problem”?– The perception of what constitutes a problem varies between individuals and societies
– Age, gender, class, race, nationality, employment and education can affect perception
– e.g. DDT (dichlorodiphenyltrichloroethane), a pesticide
• In developing countries: welcome because it kills malaria‐carrying mosquitoes
• In developed countries: not welcome, due to health risks
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Environmental science is not environmentalism
•Environmental science• The pursuit of knowledge about the workings of the environment and our interactions with it;
• Scientists try to remain objective.
•Environmentalism• A social movement dedicated to protecting the natural world and by extension, humans from undesirable changes brought about by human choices.
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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 for– Sorting fact from fiction – Developing solutions to the problems we face
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Science: Critically examining evidence
• Scientists design tests: are ideas supported by evidence?
• Explanations must:– Be testable– Resist repeated attempts to disprove it
• Accepted ideas can be applied in policy and management decisions (e.g. prescribed burning)
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The scientific method• A scientist makes an observation and asks questions of some phenomenon• The 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
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There are different ways to test hypothesesManipulative experiments yield the strongest evidence • Can show causation• Not always possible to use
Natural or correlational tests show real‐world complexity• Cannot show causation
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The scientific process is part of a larger process
• The scientific process includes peer review, publication, and debate • A consistently supported hypothesis becomes a theory, a well‐tested and widely accepted explanation• With enough data, a paradigm shift – a change in the dominant view – can occur
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Sustainability and the future of our world
• Human population growth exacerbates all environmental problems– The 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.
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Ecological footprints are not all equal
• The ecological footprints of countries vary greatly– Canada uses far more than its equal share of the world’s resources
– Developing countries have much smaller footprints than developed countries
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We face challenges in agriculture
• Expanded food production led to increased population and consumption
• 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
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We face challenges in pollution• Waste products and artificial chemicals used in farms, industries, and households
Each year, millions of people die from pollution
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We face challenges in climate• Scientists have firmly concluded that humans are changing the composition of the atmosphere• The Earth’s surface is warming
• Melting glaciers• Rising sea levels• Impacted wildlife and crops• Increasingly destructive weather
Since the Industrial Revolution, atmospheric carbon dioxide concentrations have risen by 37%, to the highest level in 650,000 years
40http://lifestyle.msn.com/your-life/living-green/staticslideshowgreenchan.aspx?cp-documentid=18995580&imageindex=7
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We 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 event
Biodiversity loss may be our biggest environmental problem; once a species is extinct, it is gone forever
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The Millennium Ecosystem Assessment
• The most comprehensive scientific assessment of the condition of the world’s ecological systems (2005); 2000 scientists from nearly 100 countries
• Major findings:• Humans have drastically altered ecosystems; • These changes have contributed to human well‐being and
economic development, but at a cost;• Environmental degradation could get much worse during
first half of this century;• Degradation can be reversed, but it requires work.
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Our energy choices will affect our future• The lives we live today are due to fossil fuels
• Machines • Chemicals • Transportation • Products
• Fossil fuels are a one‐time bonanza; supplies will certainly decline
We have used up ½ of the world’s oil supplies; how will we handle this imminent fossil fuel shortage?
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Sustainable solutions exist• We must develop solutions that protect both our quality of life and the environment– Organic agriculture– Technology– Reduce pollution– Conservation– Recycling– Renewable energy sources
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Are things getting better or worse?• Many people think environmental conditions are better• Cornucopians: Human ingenuity will solve any problem
• Some think things are much worse in the world• Cassandras: predict doom and disaster
• How 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?
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Sustainability involves meeting environmental, social, and economic goals
• Major challenge: How can humans live within the planet’s means?– Humans cannot exist without functioning natural systems
• Sustainability– 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
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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
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Summary• Environmental 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 it.
• Solving environmental problems can move us towards health, longevity, peace and prosperity.
• Environmental science can help us find balanced solutions to environmental problems.
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What can you do?
Educate yourself and others
Vote with your dollars
Vote in your politicians with the environment in mind