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CHAPTER 1 UNDERSTANDING OUR ENVIRONMENT
Welcome to ESRM100/ENVIR110 - Environmental Science! You should have a copy of the textbook, "Principles of environmental science,” Cunningham and Cunningham, 4rd edition available. Since the subject of environmental science is extremely broad, and can encompass just about anything, we will not be aiming to cover everything about environmental science, but to consider some basic principles and specific case examples, particularly those that relate to our everyday lives and are of regional importance. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
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PART 1: UNDERSTANDING OUR ENVIRONMENT
The Planet Earth Earth – our frame of reference Unique (?) in the universe Mild, relatively constant temperatures Biogeochemical cycles Millions of species Diverse, self-sustaining communities Since humans currently have little impact on matters outside our solar system, the earth will be our frame of reference. Presently, we don't know whether the universe as portrayed in science fiction shows such as "Star-Trek" (where there are nearly limitless numbers of worlds inhabited by life) is real or not; or whether the opposite perspective is correct - that we are alone in the universe. We do know that even if we are alone it is quite an interesting world in which we live. The earth includes literally millions of individual organisms, many of which are interconnected through complex ecological relationships that humans can spend their lives trying to understand, and actually make little headway in doing so. We are also discovering that the requirements for life are not as narrow as we might have once thought. For instance, research in deep ocean trenches (including that done by UW researchers) reveals an abundance of life in areas that we once thought couldn't support life at all. Here. living organisms get their energy from chemical elements whose source is deep inside of the earth rather than from the sun, the source of energy for the vast majority of organisms on earth’s surface.
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Environmental Science
Environment - the circumstances and conditions that surround an organism or a group of organisms. Environmental science - the systematic study of our environment and our place in it. Ecology - the study of an organism or organisms, the impact of the environment on them, and their impact on the environment. We'll start with three critical definitions. The environment is the set of circumstances and conditions that surround an organism or group of organisms as well as the complex of social or cultural conditions that affect an individual or community. Environmental science is the scientific study of our environment, including the role of humans. Ecology is the study of an organism or organisms, the impact of the environment on them, and their impact on the environment. We'll try and use these definitions correctly in this class even though they are often misused in everyday life. In the diagram above, notice the many disciplines, ranging from biology to history to physics, that are involved in studying environmental science.
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Part 2: Science as a Way of Knowing
Modern science has its roots in antiquity Greek philosophers Arabic mathematicians and astronomers Chinese naturalists Modern science has its roots in antiquity. It has always been amazing to me, in my readings, to find that people have long considered many of the most important questions I often find myself asking. Greek philosophers, Arabic mathematicians and astronomers, Chinese naturalists, and many others fashioned our concept of the world. The basic concepts of modern science are actually quite old, as science is based on observation and reason, which people have engaged in since ancient times. Conceivably, humans have survived (even as other species have gone extinct) partly because of their ability to observe nature, see relationships, use that knowledge to gain a competitive advantage, and pass that knowledge on to the next generation. However, this ability is not unique to humans. For instance, many animals use tools. If a single generation is not taught their use, knowledge for that use is lost. Keeping and transmitting a record of learning is an important aspect of modern science, and that is why you are here – to learn what others have figured out. More than ever, humans need to understand how the environment works, because with technology, we are now capable of impacting the environment in entirely new ways. Hopefully, in this course you will learn from the observations and records of previous environmental scientists.
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A Quote to think about regarding Ecology: The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man. [George Bernard Shaw]
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A quote to think about regarding Technology: The only two things that are infinite in size are the universe, and human stupidity. And I'm not completely sure about the universe. [Albert Einstein]
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Scientific Investigation
Deductive vs. inductive reasoning Hypothesis - a conditional explanation that can be verified or falsified Scientific theory - an explanation supported by an overwhelming body of data and experience Humans learn about nature through the process of scientific investigation. Scientific investigation depends on two types of reasoning, deductive and inductive. Deductive reasoning uses a series of logical steps to think about a phenomenon and come to a conclusion. For instance, Isaac Newton observed that nearly any object of significant density will fall downward toward the center of the earth. We would be able to deduce that an object, such as a brick, is likely to do the same thing, and pretty much be assured of being correct. In many cases, however, we don't have a general law or observation to predict specific occurrences in nature, and instead we rely on observations of specific events to predict other, similar events. This process is called inductive reasoning. Inductive reasoning (a s well as deductive reasoning) can involve formulating a hypothesis and then testing it. Scientific theory is developed when hypotheses are tested many times and the overwhelming body of data and experience supports the hypothesis. The hypothesis is then accepted as a theory. Examples of scientific theories are cell theory and the theory of evolution. Though many students may think of science as something more complicated than it is, science is actually based on the idea that our senses can tell us about how the world works. Informal science has always been an important part of human evolution.
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Deductive reasoning – going from a general principle to a testable prediction about a specific case
Inductive reasoning – taking many observations to discover patterns and produce general explanations
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Models and Natural Experiments
Simulate real environmental systems; Physical or mathematical; Provide heuristic information (suggestions of how things MIGHT be); and Are influenced by researchers' assumptions. Natural Experiments Gathering of historic evidence; and Conducted by scientists who can't test their hypotheses directly. Models are human constructs that can be used to simulate natural systems. Two basic types of models are physical and mathematical. For instance, the Pacific Science Center has a physical model of Puget Sound. This model includes a water- filled basin that has the same relative dimensions as Puget Sound, but at a smaller scale -- "rivers" where water can be input at different rates and sensors to determine the flow and levels of water under different conditions. Properties of Puget Sound that are already known, such as the low rate of flushing of water in Hood Canal, are confirmed by studying this physical model. More and more, particularly as computers become more powerful, mathematical models have been used to simulate natural systems. Mathematical models have the potential to provide information about how things might happen – they have predictive abilities. One of the main criticisms of models is that they are often influenced and created by the researcher's assumptions of how things work. That assumption may or not be true.
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Open Minds are Learning Minds
In some ways, children are the “ultimate” practical scientists…no pre-conceived bias in their investigations. However, Society uses numbers, called “statistics” to evaluate and compare things. Information known by only one person isn’t useful to Society, and communication is essential. This is one reason why scientists are rewarded so much for publishing in scientific journals. “Publish or Perish” is a real threat in academia.
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Statistics and Probability
Quantitative data Precise and easily compared Good benchmarks for measuring change. Probability Measure of how likely something is High degree of scientific certainty: 95% probability. Statistics Important tool in both planning and evaluating scientific studies Sample size, number of replications important. An additional principle of the application of science to the environment is the uses of quantitative data. Mathematics can be used to compare and quantify environmental factors fairly precisely. Using mathematics to describe the natural environment offers power. For instance, if you can quantify the size of an animal or its population, the information can be used as a benchmark for measuring changes over time. Probability is an application of statistics to math and includes measuring how likely something is to occur. There is uncertainty associated with many, if not most, of what we observe in nature. For instance, if we compare one population to another (for instance, a present and a future population), and ask if there is the same number of individuals, we may be able to estimate the two populations, but may not be able to completely measure them With the use of statistics, we can compare, with a certain amount of certainty, whether or not they are effectively the same.
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Paradigms and Scientific Consensus
All-encompassing models of the world that guide our interpretation of events Examples: Einstein's theory of relativity, plate tectonics Paradigm shift When a majority of scientists accept that the “old” explanation no longer explains new observations very well Paradigm shifts are sometimes contentious and political; often requires turnover of the “old guard”. Paradigms are a type of scientific consensus that use a model of the world that guides how we look at the environment. Good examples are Newton's "law of gravity;" "Plate tectonics," or the movements of plates in the earth's crust (which we will get into later); Einstein's theory of relatively, and other natural phenomenon we accept as fact. Paradigms are very useful in guiding our interpretation of the environment. A paradigm shift occurs when a large number of scientists accept that an old paradigm that was previously accepted no longer explains what we see. A good contemporary example is the current scientific view of climate change. In recent years, most scientists thought that a climate change was occurring, but whether or not humans were actually doing things to cause the change was in question. It seems now that the paradigm is shifting to one in which most scientists believe that human activities are responsible for climate change.
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Part 3: Thinking About Thinking
In our quest to develop environmental wisdom, we have to think about issues critically. Critical thinking includes analytical thinking (in terms of deconstructing what makes up the problem you are thinking about), logical thinking (how can ordering and trying to put things together in reasoning work), creative thinking (how could I do things differently, what's wrong with this picture and how can I change it?) and in reflective thinking (after looking at all the other situations, what does this mean?).
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Table 1.3 Steps in Critical Thinking
The table above shows some steps you can follow to think critically about an environmental problem. In each step of the way, you need to consider the information and determine what you are trying to do. For instance, what exactly is it that would bring about a successful situation? Then, ultimately, what would be the consequences of what you might do?
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Applying Critical Thinking
Identify and evaluate premises and conclusions in an argument; Acknowledge and clarify uncertainties, vagueness, ambiguities, and contradictions; Distinguish between facts and values; Recognize and assess assumptions; Distinguish source reliability or unreliability; and Recognize and understand conceptual frameworks. Applying critical thinking toward the problem could involve several steps. First, identifying the premises and the conclusions in terms of any argument that you might make is important. You need to identify and try to see uncertainties, including where things would not work out and where the problems are with the conclusions, and consider any contradiction that you may encounter. To be most successful, you must face problems up front (the worst thing in the world that can be done is to ignore problems). Also, we need to distinguish between environmental facts and societal values. Many important environmental decisions are based on politics, not science. All of these factors need to be understood within the perspective of a conceptual framework.
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Part 4. History of Conserva-tion and Environ-mentalism
Teddy Roosevelt& John Muir
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Our Conservation and Environmentalism History has four Distinct Stages:
Pragmatic Resource Conservation Moral and Aesthetic Nature Preservation Modern Environmentalism Global Environmental Citizenship
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Pragmatic Resource Conservation
President Theodore Roosevelt and his chief conservation advisor, Gifford Pinchot, believed in utilitarian conservation. Forests should be saved so they can be used to provide homes and jobs. Should be used for “the greatest good for the greatest number, for the longest time.”
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Moral and Aesthetic Nature Preservation
John Muir, first president of the Sierra Club, opposed Pinchot’s utilitarian policies. Biocentric Preservation – nature exists for its own sake, could care less about us emphasizes the fundamental right of all organisms to pursue their own interests Creation of National Park Service
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Modern Environmentalism
Rachel Carson’s Silent Spring (1962) started the modern environmental movement. awakened the public to threats of pollution and toxic chemicals to humans as well as other species modern environmentalism extends concerns to include both environmental pollution and use/misuse of natural resources.
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Global Concerns Increased travel and communication enables
people to know about daily events in places unknown in previous generations. Global environmentalism is the recognition that we share one environment that is common to all humans.
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Part 5: Current Environmental Conditions
Half the world's wetlands were lost in the last 100 years (a big problem in Louisiana bayou areas). Land conversion and logging have shrunk the world's forests by as much as 50%. Nearly three-quarters of the world's major marine fish stocks are over-fished or are being harvested beyond a sustainable rate. Soil degradation has affected two-thirds of the world's agricultural lands in the last 50 years. Thinking and planning actually do not change a thing, but they can be used to guide actions that do make changes. Society needs to recognize where things are going and try to figure out if that is where we actually want to go. For instance, currently half of the world's wetlands have been changed; some would say destroyed. Most forests have been logged, and in some cases, multiple times, leading to serious environmental problems such as erosion. Nearly all natural fisheries have been depleted, some seriously so, by humans. Soil serves as the basis for agricultural productivity (both forestry and food), and soil degradation has reduced the productivity of many agricultural lands.
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Major Causes of Environmental Degradation
(1) Population Growth Almost 6.5 billion people now occupy the earth, and we are adding about 85 million more each year. In the next decade, most population growth will be in the poorer countries - countries where present populations already strain resources and services Population growth can have a significant impact on the environment. There are now more than six billion people on the earth, and the population continues to increase dramatically. In the last few years, the rate of population increase has started to level off for the first time in recent history. This means that if population growth continue to level off, then at some point in the future, the earth’s population would stabilize. We don't know when that would occur – when world population has reached perhaps 12, 18 or 20 billion people?
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Major Causes of Environmental Degradation (cont’d)
(2) Resource Extraction and Use burning of fossil fuels destruction of tropical rainforests and other biologically rich landscapes production of toxic wastes People need resources to live. Extracting and utilizing the earth's resources to produce the great number of products (from cars to sneakers) that people in industrialized countries use has a major impact on the environment. For instance, we continue to use fossil fuels, particularly oil, at an increasing rate. What do you think might be the environmental consequences of drilling for and processing oil? People in industrialized countries rely on a great number products (in many cases toxic substances such as pesticides) that have a negative impact on the environment, and we continue to introduce these products into the environment. Some of our resources are harmed or destroyed indirectly. For example, acid rain, produced by burning coal, has damaged many forests.
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Part 6: Human Dimensions of Environmental Science
More than 1.3 billion people live in acute poverty, with an income of less than $1 (US) per day. These people generally lack access to an adequate diet, decent housing, basic sanitation, clean water, education, medical care, and other essentials. Four out of five people in the world live in what would be considered poverty in industrialized countries. The world's poorest people are often forced to meet short-term survival needs at the cost of long-term sustainability. The environment provides abundance for much of the world. However, many people (something on the order of over a billion), live at marginal levels. The daily problems they face include getting adequate food, shelter, and water. Much of the world lives in what we in the US would define as poverty. If you have ever lived in a poor country (for instance, I lived in Tanzania), you would know that nearly everybody in the country would be considered poor because they lack access to water and continuously-available, high-quality food. (On the other hand, in Tanzania, it did not get cold in the winter, and it didn't get all that hot, so, you didn't need many of the things you need here in Washington State.) In many cases, poor people are relatively desperate in terms of their short-term survival, so they are not thinking about the long-term environmental impacts of their choices. A rare and endangered species, for instance, might just be a meal to a hungry person. In some poor countries there is a general lack of education about the environment, which may mean that people in these countries don't understand the environment enough to be able to maintain adequate resources. In many cases, indigenous cultures in poor countries has been replaced by western culture, which means that the centuries-old knowledge of how to maintain natural resources has been lost. Education doesn't necessarily mean formal education, but can include a very informal education passed down from one generation to the next - how to fish or how to plant and grow plants, for example. However, as we know from our experience in this country, even being well-educated about environmental issues such as deforestation, over-fishing, or soil erosion doesn’t prevent us from over-using the world’s resources.
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There are large disparities in environmental resources among different countries. For instance, the poorest countries in the world (as shown with Table 1.4) show a per capital gross national product that is just a tiny fraction of that of the most wealthy countries. In the poorest countries, life expectancy is quite a bit lower than in wealthy countries, access to safe drinking water is available to less than half of the people, and literacy rates are much lower, especially among females. The poorest countries tend to exceed developed countries in actual birth rates, the number of births per capita per year.
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The American Lifestyle
To get an average American through the day takes about 1,000 pounds of raw materials, including 40 pounds of fossil fuels 22 pounds of wood and paper 119 gallons of water. Every year, Americans throw away some 160 million tons of garbage, including 50 million tons of paper 67 billion cans and bottles 18 billion disposable diapers. As people living in the US, we should take a look at our lifestyle. It takes an enormous proportion of the earth's resources to fuel our lifestyle. On the average, an American utilizes about a 1,000 pounds of raw materials per day. That includes a large quantity of fossil fuels, wood, paper and water. Much of that raw material is not consumed in our homes, but is utilized by farms, factories, shopping malls, universities, and other parts of our society. The US also produces an enormous amount of waste. It is illustrative to imagine how much waste you produce by multiplying your weekly output of garbage by 52 weeks per year.
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Sustainability Sustainability
Sustainable development: progress in human well-being that can be extended/prolonged over many generations, rather than just a few years. How can the nations of the world produce the goods and services needed to improve life for everyone without overtaxing the environmental systems and natural resources on which we all depend? Sustainability of the earth's resources is a key issue. When will the resources that sustain the over-consumption of industrialized nations be exhausted? Some resources are inherently sustainable because they are continuously produced by nature. For instance, forest products can be produced continuously as long as the soil resource is maintained. Other resources, such as oil, take very long time periods to produce naturally. To be truly enduring, the benefits of sustainable development must be available to all humans, not just to the members of a privileged group.
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Indigenous Peoples Indigenous peoples are generally among the least powerful, most neglected groups. In many countries, traditional caste systems, discriminatory laws, economics, or prejudices repress indigenous peoples. In many places, indigenous people in traditional homelands guard undisturbed habitats and rare species. Recognizing native land rights may safeguard ecological processes.
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And now let us end this section with a beautiful picture of the way things might be. Rob Harrison's favorite sport is fishing, which is best done in a beautiful environment. At its best, fishing is taking resources from nature in a way that doesn't greatly affect the environment.
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