Chapter 1 Understanding our Environment. Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Transcription

1 Chapter 1 Understanding our Environment Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

2 Today we are faced with a challenge that calls for a shift in our thinking, so that humanity stops threatening its life-support system. Wangari Maathai, winner of 2004 Nobel Peace Prize 1-2

3 Case Study: Saving the Reefs of Apo Island 1-3

4 1.1 Understanding Our Environment In this course you will learn about many serious environmental problems like overfishing. You will also read about promising, exciting solutions to many of these problems. 1-4

5 We Live on a Marvelous Planet The conditions on Earth are unique. Plentiful supplies of clean air, fresh water, and fertile soil are constantly regenerated by biological communities. 1-5

6 Our Planet Has an Amazingly Rich Diversity of Life Millions of species populate the earth and help sustain a habitable environment. They create complex, interrelated communities and selfsustaining ecosystems. 1-6

7 What is Environmental Science? Environmental science is the systematic study of our environment and our place in it. It is multidisciplinary. 1-7

8 1.2 Problems and Opportunities Approximately 7 billion people on Earth, we are adding about 80 million more each year. Present trends project a world population between 8 and 10 billion by The impact of that many people on our natural resources and ecological systems complicates many of the other problems we face. 1-8

9 Environmental Problems: Climate Change Human activities (burning fossil fues, clearing forests and farmlands, raising ruminant animals) have greatly increased concentrations of carbon dioxide and other greenhouse gases over the last 200 years. Climate models indicate that by 2100, if current trends continue, global mean temperatures will probably warm between about 2 and 6 C. 1-9

10 Environmental Problems: Food Supply Over the past century, global food production has increased faster than human population growth, but hunger remains a chronic problem. At least 60 million people face acute food shortages due to weather, politics, or war. 1-12

11 Environmental Problems: Clean Water 1.1 billion people lack access to safe drinking water. Every year polluted water contributes to the death of more than 15 million people. 40% of the population live in countries where water demands now exceed supplies. 1-11

12 Environmental Problems: Energy Resources Fossil fuels (oil, coal, and natural gas) presently provide around 80 percent of the energy used in industrialized countries. Supplies of these fuels are diminishing, and there are many problems associated with their acquisition and use. Investing in renewable energy and energy conservation measures could give us cleaner, less destructive options. Forest damaged by acid rain. By Getty Images on The Discovery Channel. 1-12

13 Environmental Problems: Air Quality Air quality has worsened dramatically in many areas, especially in southern Asia. Nobel laureate Paul Crutzen estimates that at least 3 million people die each year from diseases triggered by air pollution. Worldwide, 2 billion metric tons of air pollutants (not including carbon dioxide or wind-blown soil) are released each year. 1-13

14 Environmental Problems: Biodiversity loss Habitat destruction, overexploitation, pollution, and introduction of exotic organisms are eliminating species at a rate comparable to the great extinction that marked the end of the age of dinosaurs. 1-14

15 Environmental Problems: Marine Resources More than a billion people depend on seafood for their main source of animal protein. According to the World Resources Institute, more than three-quarters of the 441 fish stocks for which information is available are severely depleted or in urgent need of better management. 1-15

16 Signs of Hope: Population and Pollution Population is stabilizing. Over the past 25 years, the average number of children born per woman worldwide has decreased from 6.1 to 2.6 The UN Population Division predicts that the world population will stabilize at about 8.9 billion by the year Pollution has been decreasing in most industrialized countries. Image from:

17 Signs of Hope: Health The incidence of life-threatening infectious diseases like smallpox and polio have been reduced sharply in most countries during the past century, while life expectancies have nearly doubled. Global Health in 4 minutes. 1-17

18 Signs of Hope: Renewable Energy Renewable energy: Encouraging progress is being made in a transition to renewable energy sources. The European Union and China are developing wind energy, hydropower, solar, wave and tidal energy, and improvements in efficiency to cut reliance on fossil fuels. At the Copenhagen climate summit in 2009, the world's wealthiest countries agreed to aid developing nations in finding alternative energy technologies. 1-18

19 Signs of Hope: Conservation of Forests and Nature Preserves Deforestation has slowed in Asia. Brazil, which has led global deforestation rates for decades, is working to protect forests. Nature preserves and protected areas are on the increase. 1-19

20 Signs of Hope: Protection of Marine Resources Protecting fish nurseries represents an altogether new approach to protecting marine ecosystems. Marine reserves are being established in California, Hawaii, New Zealand, and Great Britain. 1-20

21 1.3 Human Dimensions of Environmental Science 1-21

22 Poverty Causes Environmental Damage The World Bank estimates that more than 1.4 billion people about one-fifth of the world s population live in acute poverty with an income of less than $1 (U.S.)/day. We must work to break the poverty cycle. 1-22

23 The Cost of Affluence And may we continue to be worthy to consume a disproportionate share of the planet s resources. 1-23

24 Affluence also has Environmental Costs The affluent lifestyle that many of us in the richer countries enjoy consumes an inordinate share of the world s natural resources and produces a shockingly high proportion of pollutants and wastes. The U.S., for instance, with less than 5% of the total population, consumes about 25% of commodities, such as oil, and produces 25-50% of the industrial wastes. 1-24

25 Sustainability is a Goal Sustainability is a search for ecological stability and human progress that can last over the long term. Sustainable development is meeting the needs of the present without compromising the ability of future generations to meet their own needs. 1-25

26 Where do Rich and Poor Live? About one-fifth of the world s population lives in the 20 richest countries, where the average per capita income is above $25,000 (U.S.) per year. Eighty percent of the world s population lives in middle- or low-income countries, where nearly everyone is poor by North American standards. 1-26

27 Indigenous Peoples are Guardians of Much of the World s Biodiversity Often, the 500 million indigenous people who remain in traditional homelands still possess valuable ecological wisdom and remain the guardians of littledisturbed habitats. Biopiracy 1-27

28 Cultural Diversity and Biological Diversity Often Go Together 1-28

29 Science is a Cumulative Process Good science is rarely carried out by a single individual working in isolation. Instead, a community of scientists collaborates in a cumulative, self-correcting process. The idea of consensus is important in science. Sometimes new ideas emerge that cause major shifts in scientific consensus. These great changes in explanatory frameworks ware called paradigm shifts. 1-29

30 Critical Thinking An ability to think critically, clearly, and analytically about a problem may be the most valuable skill you can learn. Critical thinking is a term we use to describe logical, orderly, analytical assessment of ideas, evidence, and arguments. 1-30

31 1.6 Where Do Our Ideas About The Environment Come From? Many of our current views on the environment are rooted in the writings of relatively recent environmental thinkers. Their work can be grouped into 4 stages: Resource conservation for optimal use Nature preservation for moral and aesthetic reasons Concern over health and ecological consequences of pollution Global environmental citizenship These stages are not mutually exclusive. 1-31

32 Peer Teach Exercise Purpose Instead of lecture, students teach their peers about the leading environmental thinkers Directions I would like each student to pick a name of an environmental thinker (a list will be provided on the next slide). Strive to become an expert on your individual. Share what you have learned with the rest of the class. 09/22/10

33 Peer Teach Exercise Create a PowerPoint of the following and make it visually appealing. Post your work in the Discussion section called Environmental Thinkers, and visit other student submissions to learn more about these important people. Below are some suggestions to include in your PowerPoint. Name of person and at least one photograph (more is better) Year born/died Profession Stage they are a part of (see text book) Focus of their environmental concern (what they cared about) Great achievements (could include an activity, a policy they created, a book they wrote, etc.) Name at least 3. Famous quote (at least one) Cite all sources and images used (APA style) 09/22/10

34 Environmental Thinkers Research one of the following and post in the discussion section. Make sure that in the subject area of your post you list the name of the person you studied. Your book will get you started but use the internet for more information. 09/22/10 President Teddy Roosevelt Gifford Pinchot John Muir Aldo Leopold Rachel Carson David Brower Barry Commoner Wangari Maathai

35 Conclusion Environmental science gives us useful tools and ideas for understanding both environmental problems and new solutions to those problems. We face many severe and persistent problems, but we can also see many encouraging examples of progress. Science helps us analyze and resolve these problems because it provides an orderly, methodical approach to examining problems. Environmental thought has evolved in response to environmental deterioration. 1-35