Unit 1 An Introduction to Environmental Science and Sustainability

Our 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 Impact on the Environment Satellite view of North America at night

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

Population 1 in 4 people live 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

Types of Natural Resources

Ecological Footprint The average amount of land, water and ocean required to provide that person with all the resources they consume Earth’s Productive Land and Water 11.4 billion hectares Amount Each Person is Allotted (divide Productive Land and Water by Human Population) 1.8 hectares Current Global Ecological Footprint of each person 2.7 hectares

Ecological Footprint Comparison

Environmental effect of technologies IPAT Model Measures 3 factors that affect environmental impact (I) I = P A T Environmental Impact Number of people Affluence per person Environmental effect of technologies

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 STOP HERE!

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 Common pool resources Garrett used Common Pastureland in medieval Europe to illustrate the struggle

Environmental Science An interdisciplinary study of human relationship with other organisms and the earth Biology Ecology Geography Chemistry Geology Physics Economics Sociology Demography Politics

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Five Stages to Addressing An Environmental Problem Five steps are idealistic Case Study: Lake Washington