1. An Introduction to Environmental Science Chapter 1 Lesson 1 – Our Island, Earth Lesson 2 – The Nature of Science Lesson 3 – The Community of Science

2. Our Island, Earth The environment includes all the living and nonliving things with which organisms interact. Non-living = “abiotic” factors Living = “biotic” factors Non-living examples: continents, oceans, clouds, and icecaps Living examples: animals, plants, forests

4. Humans and the Environment The word environment is often used to mean the “natural” world, but humans are a part of nature. Humans interact with the environment and depend on a healthy planet for the things we need – including air, water, food, and shelter. Without a healthy planet, humans can not survive.

5. Understanding Human Influences Many of the luxuries we enjoy today have harmed the natural systems that we depend on for resources. Environmental Science is the study of how the natural world works, how our environment effects us, and how we affect our environment. Understanding the interactions between humans and the environment is the first step toward solving environmental problems.

6. Environmental Scientists The many problems facing the environment offer scientists countless opportunities to come up with creative solutions. Environmental scientists study issues that are important to our world and its future.

7. Environmental Science vs. Environmentalism Environmental science is an interdisciplinary field. Environmental scientists have expertise in many areas including ecology, earth science, chemistry, biology, economics, political science, and other areas. Environmentalism is a social movement dedicated to protecting the natural world – and by extension, people – from undesirable changes brought about by human actions.

8. Population Up, Resources Down There are limits to the natural resources available on the planet Earth. Renewable natural resources are those that are naturally replenished, or renewed, over short periods such as grains and fruits. Nonrenewable natural resources such as coal and oil are naturally formed much more slowly than we use them. Once these resources are used up, they are gone forever.

10. Sustainability Between the two extremes of natural resources are those like fresh water, timber, and soil that can renew themselves given enough time. Resource use is considered sustainable if it can continue at the same rate into the forseeable future. If these resources are used at a rate faster than they can be renewed, then we will run out of them.

11. Human Population Growth For nearly all of human history, only a few million people lived on Earth at any one time. Today, we add about 78 million people to the planet each year, or more than 200,000 people every day! Though the rate of population growth is slowing, there are about 7 billion people who call the Earth home.

12. The Tragedy of the Commons Garret Hardin argues that when a resource is left unregulated, individuals are motivated to increase the consumption of that resource. Since no one is responsible for regulating the use, the resource is used until it is depleted and there is none left for anyone to use.

14. The Agricultural Revolution Two events in recent human history have accounted for the increase in population size. About 10,000 years ago, human populations shifted from hunter-gatherer societies to an agricultural way of life. This was known as the Agricultural Revolution. At this time, people began to grow crops, raise domestic animals, and live in villages which allowed them to live longer lives and produce more children who survived to adulthood.

15. The Industrial Revolution In the early 1700s, the Industrial Revolution began. The Industrial Revolution describes the shift from rural live, with animal-powered agriculture, and handmade manufacturing, to an urban society powered by nonrenewable energy sources. These nonrenewable energy resources, such as oil, coal, and natural gas are known as fossil fuels.

16. The Industrial Revolution During the Industrial Revolution many advances were made in science and industry. Medical technology advanced, sanitation improved, and agricultural production increased. Humans lived longer and had healthier lives.

17. The Problem with Population Growth During and soon after the Industrial Revolution, population growth was thought of as a good thing. Higher birthrates allowed families to have more children to help support the family and more people to enter the workforce. British economist Thomas Malthus had a different opinion. He believed that uncontrolled population growth would lead to starvation, war, and disease as humans outgrew their natural resources.

18. The Population Bomb In his 1968 book, Paul Erlich warned that population growth will have disastrous effects on human welfare. He predicted that the rapidly increasing human population would cause famine and wars that would consume civilization by the end of the twentieth century. Though his predictions were on target, many scientists think it is only a matter of time till this comes true.

20. Ecological Footprint The amount of resources that humans consume can be measured using the “ecological footprint,” developed in the 1990s by environmental scientists Mathis Wackernagel and William Rees. An ecological footprint expresses the environmental effects of an individual or population in terms of the total amount of land and water required: (1) to provide the raw materials the individual or population consumes and (2) to dispose of or recycle the waste the individual or population produces.

21. Learning From the Past In order to avoid the tragedy of the commons, many argue that private regulation of natural resources is needed. This is possible for resources such as minerals or farmland, but is much more difficult for worldwide resources such as the oceans or ozone layer.

22. What Science Is and Is Not Modern scientists describe science as a systematic process for learning about the world and testing our understanding of it. Science also refers to the body of knowledge that results from the process of learning.

23. Science Scientists work exclusively within the natural world and is therefore governed by certain rules. Scientists examine the natural world by collecting evidence and testing ideas. Nothing in science can be absolutely proven no matter how much evidence is collected. Instead, ideas can be supported through rigorous testing.

24. The Process of Science Scientists engage in many activities as part of their quest for knowledge and understanding. They ask questions, make observations, seek evidence, share ideas and analyze data.

25. Exploration and Discovery Many scientific investigations begin with an observation. This observation may be unexpected or planned, casually viewed or carefully measured. Early in an investigation there are usually many questions being asked. Through discussion and research, these questions may be clarified and become more focused.

26. Testing Scientific Ideas A hypothesis is a testable idea that attempts to explain a phenomenon or answer a scientific question. Scientists develop hypotheses by asking questions and deciding what questions they can test. Scientists use hypotheses to generate predictions, which are specific statements about what we would expect to observe if the hypotheses are true. When a scientist can not make direct observations of a phenomenon, they may use a model to recreate the phenomenon and generate predictions.

27. Gathering Data An experiment is an activity designed to test the validity of a prediction or hypothesis. In an experiment, a scientist manipulates different variables to test their idea. An independent variable is a variable that the scientist manipulates. A dependent variable is one that depends on the conditions set up in the experiment.

28. Observational Study Some hypotheses can not be tested through experiments because the experiment may be too expensive or dangerous. Observational studies provide another key source of scientific evidence. In an observational study, scientists look for evidence in the natural world that would help confirm or contradict the predictions generated by their hypotheses.

29. Controlled Variables and Repetition When studying cause-and-effect relationships it is important for scientists to keep their variables constant. A controlled variable is one that is kept constant in a study. Controlled studies, in which all variables are controlled except one, allow scientists to be more confident that any differences observed were caused by the factor they are investigating. Whenever possible, scientists try to repeat their tests to show that their results are consistent.

30. Interpreting Data Scientists collect and record data, or information, from their studies. Quantitative data, or data involving numbers, is especially useful since it is precise and easy to compare. By analyzing their data, scientists can see if there is enough evidence to support or refute their hypothesis.

31. The Community of Science Scientific work takes place within a community of peers. As scientists work on an idea, they share their findings through writing and professional conferences. By working together, scientists can improve on their individual work.

32. Community Analysis and Feedback When researchers submit their work for publication it goes through a process of peer review. Other scientists who specialize in the topic of the paper examine it and provide comments and criticism. As scientists continue to collect information, ideas can change. Many ideas that were once commonly accepted are now known to be invalid.

33. Scientific Theory-Building Theories are broad explanations that apply to a wide range of situations and observations. Keep in mind that the scientific use of the word theory is not the same as the common use. A scientific theory must effectively explain a phenomenon, make accurate predictions in a wide range of situations, and have undergone extensive, rigorous testing.

34. Culture and Worldview People of different cultures may differ in their ethical standards. Culture is the ensemble of knowledge, beliefs, values, and learned ways of life shared by a group of people. Culture, together with personal experience, influences each person’s perception of the world and his or her place within it, something described as the person’s worldview.

35. Ethics Ethics is a branch of philosophy that involves the study of behavior: good and bad, right and wrong. The term ethics can also refer to the set of moral principles or values held by a person or a society. People’s decisions are guided by their own set of ethical standards. Governments also base decisions on ethical codes.

36. Ethics and the Environment The application of ethical standards to relationships between humans and their environment is known as environmental ethics. Three important ethical standards in environmental ethics are antrhopocentrism, biocentrism, and ecocentrism.

37. Anthropocentrism This describes a human-centered view of our relationship with the environment. An antrhopocentrist places the highest value on humans and human welfare. A person with these views would base decisions on the impacts on human health and economies.

38. Biocentrism This belief gives value to all living things. In this perspective, nonhuman life has ethical standing, so a biocentrist evaluates actions in terms of their overall effect on living things, both human and nonhuman. Some biocentrists believe that all living things are equal while others place more importance on certain organisms than others.

39. Ecocentrism This perspective judges actions in terms of their benefit or harm to the integrity of whole ecological systems, which consist of both living and nonliving elements and the relationships among them. An ecocentrist would value the well-being of species, communities, or ecosystems over the welfare of a given individual.

40. Environmental Justice The environmental justice movement promotes the fair and equitable treatment of all people with respect to environmental policy and practice, regardless of their income, race, or ethnicity. It is commonly accepted that disadvantages populations tend to be exposed to a greater share of pollution, hazards, and environmental degradation.