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Chapter # 1 Introducing Environmental Science and Stability. Reading this Week:. Chapter # 1 – “Hooknose”. In-class Discussion Readers:. Chapter # 1 - Me Chapter # 2 – David Dudley Chapter # 3 – Elizabeth Goodrich Chapter # 4 – James McLeod
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Reading this Week: Chapter #1 – “Hooknose”
In-class Discussion Readers: Chapter #1 - Me Chapter #2 – David Dudley Chapter #3 – Elizabeth Goodrich Chapter #4 – James McLeod Chapter #5 – Labecca Hampton and Jessica Vidal Chapter #6 – Patrick Grennan and Scott Arnold Chapter #7 – William Arnold Chapter #8 – Crissy Overgard Chapter #9 – Juan Rodriguez
The Environment (Earth) • Life has existed on earth for 3.8 billion years • Earth well suited for life • Water covers ¾ of planet • Habitable temperature • Moderate sunlight • Atmosphere provides oxygen and carbon dioxide • Soil provides essential minerals for plants • But humans are altering the planet; not always in positive ways
Human Impacts on Environment Population • Earth’s Human Population is over 6 billion • Growing exponentially • Expected to add several billion more people in 21st century • Increase will adversely affect living conditions in many areas of the world www.census.gov/main/www/popclock.html
Population • Globally, 1 in 4 people lives in extreme poverty • Cannot meet basic need for food, clothing, shelter, health • Difficult to meet population needs without exploiting earth’s resources
Gap Between Rich and Poor • Highly Developed Countries (HDC) • Complex industrialized bases, low population growth, high per capita incomes • Ex: US, Canada, Japan • Less Developed Countries (LDC) • Low level of industrialization, very high fertility rate, high infant mortality rate, low per capita income • Ex: Bangladesh, Mali, Ethiopia
Overpopulation • Human Overpopulation • Too many people in a given geographic area • Problem in many developing nations • Consumption Overpopulation • Each individual in a population consumes too large a share of the resources • Problem in many highly developed nations
Ecological Footprint • The average amount of land, water and ocean required to provide that person with all the resources they consume
Ecological Footprint Comparison 9.6 hectares
Environmental Sustainability • The ability to meet current human need for natural resources without compromising the needs of future generations • Requires understanding: • The effects of our actions on the earth • That earth’s resources are not infinite
An Example:Tragedy of the Commons • Garrett Hardin (1915-2003) • Solving Environmental Problems is result of struggle between: • Short term welfare • Long term environmental stability and societal welfare • Garrett used Common Pastureland in medieval Europe to illustrate the struggle.
Sustainable Development • Economic development that meets the needs of the present generation without compromising future generations.
Environmental Science • An interdisciplinary study of human relationship with other organisms and the earth • Biology • Ecology • Geography • Chemistry • Geology • Physics • Economics • Sociology • Demography • Politics
Earth As a System • System • A set of components that interact and function as a whole • Global Earth Systems • Climate, atmosphere, land, coastal zones, ocean • Ecosystem • A natural system consisting of a community of organisms and its physical environment • Systems approach to environmental science • Helps us understand how human activities effect global environmental parameters
Earth Systems • Most of earth’s systems are in dynamic equilibrium or steady state (resiliency). • Rate of change in one direction equals that in the other • Feedback • Change in 1 part of system leads to change in another. • Negative feedback- change triggers a response that counteracts the changed condition. • Positive feedback- change triggers a response that intensifies the changing condition.
Controls and Variables in Experiment • Variable • A factor that influences a process • The variable may be altered in an experiment to see its effect on the outcome • Control • The variable is not altered • Allows for comparison between the altered variable test and the unaltered variable test
Inductive and Deductive Reasoning • Inductive Reasoning • Used to discover general principles • Seeks a unifying explanation for all the data available • Ex: • FACT: Gold is a metal heavier than water. • FACT: Iron is metal heavier than water. • FACT: Silver is a metal heavier than water. • CONCLUSION (based on inductive reasoning): All metals are heavier than water. • Conclusions reached with inductive reasoning may change with new information.
Inductive and Deductive Reasoning • Deductive Reasoning • Proceeds from generalities to specifics • Adds nothing new to knowledge, but makes relationships (possible cause and effect) and associations (not cause and effect) among data more apparent. • Ex: • GENERAL RULE: All birds have wings. • SPECIFIC EXAMPLE: Robins are birds. • CONCLUSION (based on deductive reasoning): All Robins have wings.
Five Stages to Addressing An Environmental Problem • Five steps are idealistic • Real life is rarely so neat, but it does allow for solutions. • Following Slides are Case Study Using the Five Stages
Assessing Environmental ProblemCase Study: Lake Washington • Large, freshwater pond • Suburban sprawl in 1940’s • 10 new sewage treatment plants dumped effluent into lake. • Effect = excessive cyanobacteria growth that killed off fish and aquatic life (nitrogen & phosphorous).
Assessing Environmental ProblemCase Study: Lake Washington • Scientific Assessment • Aquatic wildlife assessment done in 1933 was compared to the 1950 assessment • Hypothesized treated sewage was introducing high nutrients causing growth of cyanobacteria • Risk Analysis • After analyzing many choices, chose new location (freshwater) and greater treatment for sewage to decrease nutrients in effluent
Assessing Environmental ProblemCase Study: Lake Washington • Public Education/Involvement • Educated public on why changes were necessary • Political Action • Difficult to organize sewage disposal in so many municipalities • Changes were not made until 1963! • Evaluation • Cyanobacteria slowly decreased until 1975 (gone)
Assessing Environmental ProblemCase Study: Lake Washington • Results!
Your First Assignment is. . • From where does your energy come? • Focus on this campus. • Focus on this building. • Use your ideas to solve simple questions: • A small, 1-page response is due next Wednesday (10 pts.) The electrical source for this building originates ????? How much CO2 does this building put into the atmosphere each school year?