Environmental Science Is a Study of Connections in Nature Everything around us, living and non-living Environmental science: interdisciplinary science connecting information and ideas from Natural sciences: (ex. biology, geology, chemistry) Social sciences: (ex. politics, economics) Humanities: ethics, philosophy

Environmental Science Is a Study of Connections in Nature How nature works How the environment affects us How we affect the environment How to deal with environmental problems How to live more sustainably

Sustainability Sustainability: when the earth’s natural systems and human cultural systems survive, flourish, and adapt for future generations to survive My personal view as to how we should look at the problems The earth has been around for 4.5 Billion years…the earth will go on with or without us Sustainability is about what humans and societies will look like

From Simple Cell to Homo Sapiens Figure 1.2: Here, the span of Homo sapiens sapiens’ time on earth is compared with that of all life beginning about 3.5 billion years ago. If the length of this time line were 1 kilometer (0.6 miles), humanity’s time on earth would occupy roughly the last 3 one-hundredths of a millimeter. That is less than the diameter of a hair on your head—compared with 1 kilometer of time. Fig. 1-2, p. 7

Three Principles of Sustainability Reliance on solar energy and its renewable derivatives Root energy source for earth Biodiversity Maintaining variety and adaptability of natural systems and species Chemical cycling / Nutrient cycling Circulation of chemicals through the environment and living organisms Energy from sun is starting point, but all other energy types (aside from nuclear) related to solar

Three Pillars of Sustainability Environmental Healthy environment Social Healthy government Economic Healthy economy All 3 needed to maintain sustainable living. But they are not always harmonious…ex. Economic decisions might lead to environmental. damage

Sustainability Has Certain Key Components Natural capital – The resources available to us Natural resources: useful materials and energy in the air, water and earth Think about it like money in the bank earning interest Capital = Money we have available Sustainable = we spend money without losing capital (only use the interest) Unsustainable = we spend more money and leave less capital (leave less in the bank)

Natural Capital = Natural Resources + Natural Services Figure 1.4: These key natural resources (blue) and natural services (orange) support and sustain the earth’s life and human economies (Concept 1-1a). Fig. 1-4, p. 9 8

We Are Living Unsustainably Environmental degradation: wasting, depleting, and degrading the earth’s natural capital Happening at an accelerating rate

Natural Capital Degradation Figure 1.9: These are examples of the degradation of normally renewable natural resources and services in parts of the world, mostly as a result of rising populations and resource use per person. Fig. 1-9, p. 13

Some Sources Are Renewable and Some Are Not Renewable resource Several days to several hundred years to renew E.g., forests, grasslands, fresh air, fertile soil Sustainable yield Highest rate at which we can use a renewable resource without reducing available supply 11

Some Sources Are Renewable and Some Are Not Nonrenewable resources Energy resources Metallic mineral resources Nonmetallic mineral resources Can we Reuse / Recycle nonrenewable resources?

Countries Differ in Levels of Unsustainability (1) Economic growth: increase in output of a nation’s goods and services Gross domestic product (GDP): value of all goods and services produced by all businesses operating within a country Per capita GDP: GDP/population of a country Why per capita gdp?

Countries by Gross National Income per Capita Figure 2 This map shows high-income, upper-middle income, lower-middle-income, and low-income countries in terms of gross national income (GNI) PPP per capita (U.S. dollars) in 2008. (Data from World Bank and International Monetary Fund) Supplement 8, Fig 2

Ecological Footprints: A Model of Unsustainable Use of Resources Ecological footprint: the amount of land and water needed to provide you your current

Four Basic Causes of Environmental Problems Population growth Wasteful and unsustainable resource use Poverty Harmful environmental costs of things we buy are not included in their price

Prices Do Not Include the Value of Natural Capital Companies do not pay the environmental cost of resource use Goods and services do not include the harmful environmental costs Companies receive tax breaks and subsidies Economy may be stimulated but there may be a degradation of natural capital

IPAT is Another Environmental Impact Model I = Environmental impact P = Population A = Affluence T = Technology

Exponential Growth of Human Population Figure 1.18: Exponential growth: The J-shaped curve represents past exponential world population growth, with projections to 2100 showing possible population stabilization as the J-shaped curve of growth changes to an S-shaped curve. (This figure is not to scale.) (Data from the World Bank and United Nations, 2008; photo L. Yong/UNEP/Peter Arnold, Inc.) Fig. 1-18, p. 21

Technology Increases Population Figure 1.16: Technological innovations have led to greater human control over the rest of nature and to an expanding human population. Fig. 1-16, p. 19

IPAT Illustrated I = P x A x T Figure 1.14: Connections: This simple model demonstrates how three factors—number of people, affluence (resource use per person), and technology—affect the environmental impact of populations in less-developed countries (top) and more-developed countries (bottom). Fig. 1-14, p. 17