Presentation on theme: "Marine Environment Protection MAREN 211"— Presentation transcript:
1Marine Environment Protection MAREN 211 An Introduction to Environmental SciencePart A
2This lecture will help you understand: The nature of environmental scienceNatural resources and their importanceThe scientific method and the scientific processPressures on the global environmentSustainability
3The “environment” Consists of both: Biotic factors (living things) and Abiotic factors (nonliving things)that surround us and with which we interact.
4Humans and the environment We humans exist within the environment and are a part of the natural world.Like all other species, we depend for our survival on a properly functioning planet.Thus, our interactions with our environment matter a great deal.Environmental science is the study of how the natural world works, how our environment affects us, and how we affect our environment.
5Natural resourcesRenewable resources like sunlight cannot be depleted.Nonrenewable resources like oil CAN be depleted.Resources like timber and clean water are renewable only if we do not overuse them.
6Global human population growth Our population has skyrocketed to over 6 billion.The agricultural and industrial revolutions drove population growth.The industrial revolution entailed a shift to an urban society powered by fossil fuels.
7Thomas Malthus ( )Population growth will lead to starvation, war, disease.Death rates check population unless birth rates are lowered.Today, Paul Ehrlich (The Population Bomb, 1968) is called “neo-Malthusian.”
8The tragedy of the commons Garrett Hardin, 1968:In a “commons” open to all, unregulated use will deplete limited resources.
9The “ecological footprint” The “ecological footprint” is the area of land and water needed to produce the resources a person or population uses, plus the amount needed to dispose of their waste.
10Environmental science … can help us avoid mistakes made by past civilizations.On Easter Island, people annihilated their culture by destroying their environment.
11Environmental science How does the natural world work?How does our environment affect us?How do we affect our environment?Applied goal: Developing solutions to environmental problems.
12What is an “environmental problem?” Definitions differ.The pesticide DDT:Was thought safe in the 1950sIs known to be toxic todayBut is used widely in Africa to combat malaria
13Environmental science … is an interdisciplinary field, drawing on many diverse disciplines.
14Environmental science … is NOT the same as environmentalism.It is science, NOT advocacy.
15Marine Environment Protection MAREN 211 An Introduction to Environmental SciencePart B
16The nature of scienceA systematic process for learning about the world and testing our understanding of itA dynamic process of observation, testing, and discoveryAnd the accumulated body of knowledge that results from this process
17Applications of science Policy decisions and management practices are applications of science.Prescribed burning, used to restore forest ecosystems altered by human suppression of fire.
18Applications of science Technology is another application of science. Energy-efficient methanol-powered fuel cell car from DaimlerChrysler
19Scientific method: Assumptions Fixed natural laws govern how the universe works.All events arise from causes, and cause other events.We can use our senses and reason to detect and describe nature’s laws.
20Scientific methodA step-by-step method for testing ideas with observations
21Scientific method Scientists use educated guesses called hypotheses to generate predictionsthat are then tested experimentally.Results may reject or fail to reject a hypothesis.Results never confirm a hypothesis, but only lend support to it by failing to reject it.
22Experiments Manipulative experiments are strongest. Natural or correlational ones are often necessary.
23Scientific processPeer review, publication, and debate are parts of the larger scientific process.
24Hypothesis, theory, and paradigm Hypothesis = an educated guess, to be testedTheory = a well-tested and widely accepted explanation, validated by much previous researchParadigm = a dominant view; may shift if new results show old results or assumptions to be wrong
25Marine Environment Protection MAREN 211 An Introduction to Environmental SciencePart C
26The state of the world: Population Human population growth exacerbates all environmental problemsThe rate of growth has slowed, but we still add over 200,000 people to the planet each day
27The state of the world: Agriculture One of humanity’s greatest achievements… but has profoundly altered our environment. We have converted nearly half of Earth’s land surface for farming, grazing, and timber production.
28The state of the world: Pollution Waste products and artificial chemicals pollute air, water, and land worldwide We are reducing some pollution, but it still causes millions of premature deaths each year.
29The state of the world: Climate Global climate change may be our most pressing pollution challenge.It likely contributes to glacial melting, sea-level rise, impacts on wildlife and crops, and increased destructive weather.Since the industrial revolution, atmospheric carbon dioxide concentrations have risen by 31% to a level not seen in over 400,000 years.
30The state of the world: Biodiversity Habitat destruction and other causes have driven many species extinct, and threaten many more Biodiversity loss is perhaps our biggest environmental problem, because we cannot correct our mistakes later: Once a species is extinct, it is gone forever.
31Solutions must be global and sustainable Globalization is influencing the nature of most environmental issues.The Millennium Ecosystem Assessment, the most comprehensive scientific assessment of the world’s current ecological problems, documents this challenge.Our increased global interconnectedness sets the stage for novel and effective solutions.
32The state of the world: Solutions Thankfully, we may be able to develop solutions to many environmental problems Alternative energy sources are one of the many solutions you will encounter in this course.
33Sustainability The key concept for our future: Limiting human impact on the natural world so that our civilization can continue to exist
34Sustainable development UN: Development that “meets the needs of the present without sacrificing the ability of future generations to meet theirs”.
35ConclusionEnvironmental science helps us understand our relationship with the environment and informs our attempts to solve and prevent problems.Identifying a problem is the first step in solving it.This book balances discussion of problems with a focus on solutions and the creation of a better world.
36QUESTION: Review Which is a nonrenewable natural resource? a. Sunlight b. Petroleumc. Timberd. FreshwaterAnswer: b
37QUESTION: Review Which statement is FALSE? a. Our environment includes living and nonliving elements.b. Thomas Malthus favored population growth.c. Environmental science includes multiple disciplines.d. Theories are better supported by evidence than are hypotheses.Answer: b
38QUESTION: Review Which is NOT an application of science? a. Policy decisionsb. Technologiesc. Experimental resultsd. Management practicesAnswer: c
39QUESTION: ReviewWhy has biodiversity loss been called our biggest environmental problem?a. It exacerbates all other environmental problems.b. Problems like pollution can be reversed, but once extinctions happen, they are irreversible.c. It is proceeding more quickly than all other problems.d. No one has claimed this; pollution is the biggest problem.Answer: b
40QUESTION: Weighing the Issues What do you think is the best way to combat the “tragedy of the commons”?a. Sell the commons into private hands, so owners have incentive to manage resources.b. Have government regulate the amount of resources individuals take from the commons.c. Have users work out cooperative systems among themselves to police resource use.Answer: any
41QUESTION: Weighing the Issues Increasing world agricultural production could allow us to feed more people. Should this be a goal for the world?a. Yes, because it could alleviate hunger and poverty.b. No, because it could speed population growth, causing more poverty and environmental degradation.Answer: any
42QUESTION: Interpreting Graphs and Data Population increase over the last 500 years has been…?a. Equal to that of the previous 500 yearsb. More than that between 10,000 and 500 years agoc. Less than that between 10,000 and 500 years agod. Equal to that of the previous 5,000 yearsAnswer:b
43QUESTION: Interpreting Graphs and Data What happens if results fail to reject a hypothesis?a. The hypothesis is proven to be true.b. The hypothesis is supported, but not confirmed.c. The hypothesis may be retested in a different way, with new predictions.d. Both b and c are true.Answer:d