Self-regulating mechanism of Earth

Transcription

1 06 Self-regulating mechanism of Earth 1. SHORT SUMMARY Total duration of this lesson: 45 minutes What will the students learn: Students will acquire new knowledge about the Gaia theory and the positive and negative feedback mechanisms that constitute the Earth s self-regulating mechanism. What will the students do during this lesson: Watch videos, answer questions, learn about a green entrepreneur and design questions for an interview with him. What skills are the students going to improve? o Research skills o Analysis and synthesis of information o Presentation of results o Empathy and emotional intelligence o Critical thinking o Creativity o Teamwork o Holistic thinking and system thinking o Responsibility o Sustainability mindset Cross-curricular links: o Physics o Geography o Biology o Economy / entrepreneurship o Foreign languages o History Materials needed: o Multimedia projector o Laptop / computer with speakers o Internet connection in the classroom (if there is no Internet in your classroom, you can download the online videos in this lesson in advance and bring them on a flash drive, or alternatively you can ask students to form groups and use their smartphones/tablets in order to watch the videos) 45

2 Lesson 06 CORE 2. INTRO THE GIST OF IT (2 min.) Tell the students that today they will find out more about the Earth s self-regulating mechanism which is essential for understanding the issue of climate change better. Begin by asking these questions and collecting some answers from the class: What is a greenhouse? Why do you think it is called a greenhouse? Do you think the greenhouse effect is something good or something bad? Tell the students that by the end of the lesson they will know much more about how the greenhouse effect works and how it is connected with the quality of life of people. CORE 3. THE THEORY (20 min.) 1. Greenhouse gases Begin by asking the students: Do you know what the average temperature on the Moon during the day is? How about during the night? How about Earth s average temperatures? Do you know what the coldest and warmest temperatures ever recorded on Earth are? Gather some guesses from the students without telling them the correct answer now they will find it out themselves in a couple of minutes. You can record the answers on the whiteboard. Tell the students that everyone has heard of the greenhouse effect and thinks of it as an evil phenomenon, but the greenhouse effect makes the Earth livable. This video will help the students understand how greenhouse gases work. How do greenhouse gases actually work? (3:08 min.) Some other questions that you could ask after or before the video: What is the role of the atmosphere for the Earth? (During the day, the sun warms the Earth s atmosphere up and a certain amount of the heat is trapped by the greenhouse gases in the air the same way the heat is trapped in a greenhouse in a garden.) Why is infrared radiation so important for the Earth? (Because thanks to it heat remains in the Earth s atmosphere and keeps our planet warm.) Which are the chemical compounds we can be grateful to for absorbing infrared radiation? (The most important greenhouse gases are CO2, nitrogen oxides, methane. Without greenhouse gases, the temperature of the Earth would be near -18 C instead of the much warmer and really livable 15 C.) Check with the class if they guessed correctly the temperatures on the Moon and the Earth. 2. Timelines and temperature fluctuations Continue the theoretical part by telling the students that during the history of the Earth, the greenhouse gas rate in the atmosphere and consequently the temperature changed in wide ranges that caused big changes in life on Earth. Choose one of the timelines below and try to decipher it together with the students by asking them questions that will help them look at details: 46

3 Self-regulating mechanism of Earth a. Option 1: Average Earth temperatures from times long forgotten until today Source: Earth-over-Geologic-Time-Note-the-use-of You can ask the students: What is the time scale of this timeline what time period does it cover? What were the average Earth temperatures during the coldest period visible on the timeline and when was it? When is the hottest period and what are the likely projections for the future? If the students ask about the terms on the timeline (Cretaceous warm peak, Holocene optimum, etc.), you may want to give them a task to check them at home and report next time. b. Option 2: Timeline of temperatures intertwined with important events in mankind s history If you would like to focus on a more recent timeframe (starting at years BC) you can choose to work with this timeline: You can ask several questions to help the students walk their way through the graph, such as: Which year is the vantage point for the timeline in terms of temperature? (It is the average temperature.) What was the temperature during the Ice Age? (-4 degrees) When in the Earth s history did temperatures start to reach modern levels? (After the year 9000 BC.) What happened during the Little Ice Age? (Temperatures dropped.) What are the projections about the global average temperature for the year 2100 if the current trend continues? (We can expect to reach +4 degrees as compared to the average.) 3. Earth s self-regulating mechanism The third important area in this lesson s theoretical part is about the Earth s self-regulating mechanism. Tell the students that the atmosphere s composition changed dramatically during the geological history because of many factors: super-volcanoes erupted and emitted gases and dust, meteors 47

4 Lesson 06 arrived to Earth and caused dust clouds, warm periods led to methane emissions from vast permafrost areas, plants colonized land and the oxygen level went to never seen heights (35%; by way of comparison, the current level is 21%). So it s obvious that there were abiotic and biotic factors that changed the atmosphere. The amplitude of change was sometimes really extreme, but the temperature always tended to return back to a normal average of C. But how is that possible? It is because the Earth is a self-regulating system, behaves as an organism that has an optimal state, an equilibrium. Life on Earth helps to maintain the environment that is suitable for its existence up to a tipping point, when the impact is too high and the system can t handle it, so a new equilibrium is formed. Systems have two feedback mechanisms to react to a disturbance: positive and negative. Negative feedback counteracts the initial impact, i.e. reduces the change it causes and it is the most important process in ecology that keeps natural systems stable. Positive feedback amplifies the initial impact, makes it stronger. Feedback mechanism: A process that allows a system (e.g. climate) to self-regulate in response to a change (such as increasing greenhouse gases). This theory about the Earth is called Gaia Theory and was described by James E. Lovelock more than 50 years ago. It is not proven scientifically yet but more and more signs show that it is true. Play the two short videos below to help your students get acquainted with the fundamentals of the Gaia Theory. a. James Lovelock Explains Gaia Hypothesis on The Sacred Balance : youtube.com/watch?v=44yitg7covi (4:29 min.). David Suzuki talks with James Lovelock about the origins of his Gaia hypothesis, which suggests that the Earth is one organism. What was Mr. Lovelock s revelation and what did he realize one afternoon? (That what regulates our atmosphere and keeps it constant for millions of years must be life itself, since the atmosphere is made up of gases that all come from living organisms. The crucial elements cycle through the Earth making life possible and maintaining it.) Who is Gaia? (In Greek mythology, Gaia is the personification of the Earth and mother of all life.) b. What is Gaia Theory in Everyday Terms? : watch?v=6rfqros71uo (1:06 min.). Our ancestors knew about the wholeness of the Earth and how it is one big organism in non-scientific terms, they just had that knowledge in themselves. What kind of a system is the Earth, according to Gaia theory? (A single physiological system whose parts are very closely linked with each other as in a single organism.) How could you describe the meaning of Gaia theory with one word? (Wholeness.) 48

5 Self-regulating mechanism of Earth 4. ENTREPRENEUR PROFILE Tell the students that today they are going to get to know the American entrepreneur Martin Ogle. He is actually the person that they just saw in the short video, explaining about the Gaia theory. Distribute the following text to the students and ask them to read it. Ask them to pay attention and underline the parts of it which address the following questions: What is Martin s main field of knowledge and expertise? Why did Martin decide to start his business? How was the business that Martin started related to his main field of expertise? What does Martin s business actually do? Does he provide a product or a service? What does Martin think the word entrepreneurial means? CORE (11 min.) Martin was born and raised much of his younger life in South Korea. He received Bachelor s (1982) and Master s (1984) degrees in Wildlife Biology from Colorado State and Virginia Tech University, respectively. He was Chief Naturalist for the Northern Virginia Regional Park Authority in the period While working there, he implemented a variety of programs on and working demonstrations of sustainability. In 2010, Martin received the Washington Academy of Sciences Krupsaw Award for Non-Traditional Teaching for outstanding teaching in informal and non-academic settings. In 2012, he was presented the Arlington Green Patriot Award that recognizes outstanding work in sustainability. For more than 20 years, Martin has presented lectures, courses and workshops on Gaia Theory to public groups, universities, environmental organizations, and other audiences. He has spoken in 8 states, Washington, D.C., Puerto Rico, Canada and South Korea. In 2006, Martin organized a major conference on Gaia Theory in Arlington, VA, that led to publication of the book Gaia in Turmoil (MIT Press, 2009). In 2012, Martin moved to Colorado and started Entrepreneurial Earth LLC to promote sustainability through an understanding of human systems as part of Earth s living systems. Entrepreneurial Earth LLC helps companies, organizations and individuals achieve their sustainability goals and engage their innate human creativity to envision and implement sustainable ways of working and living. The word entrepreneurial is most often associated with business, but is actually a wonderful synonym for creativity in general. Working with author and business educator, Larry Robertson, Martin Ogle coined the term Entrepreneurial Earth to reflect the realization that the human mind is an extension of Earth itself and to help tap into the power of this viewpoint. Martin believes that the power of entrepreneurship isn t limited to the few every one of us has the opportunity to tap it. He quotes Nobel Peace Prize Winner Muhammad Yunus as saying that entrepreneurship is in every human being and in everything human. Whether human entrepreneurship is ultimately harmful or helpful to human society and the Earth systems upon which we depend is really up to us how will we choose to use our creativity? As long as we are here, we human beings will always be doing something. Viewing what we do as an extension of Earth herself gives us an entirely different perspective than if we see ourselves as separate. 49

6 Lesson 06 The Entrepreneurial Earth mindset opens up a new paradigm of business. Entrepreneurial Earth reminds environmentalists that business is not inherently unsustainable. Viewing business and entrepreneurship as simply one face of Earth s living system allows us to engage our innate human creativity to envision and implement sustainable ways of living that are consistent with human nature and Nature as a whole. Sources: and After the students are finished reading the text and underlining, collect several answers. OPTIONAL 5. PRACTICAL ACTIVITY (7 min.) We suggest just one option for a practical activity for this lesson. Do it together with the homework activity, only if you manage to go through the theory and the case study quickly enough. Here are the instructions of how to set it up for the students. You need to divide them into groups so that they could work together. Interview an entrepreneur! Imagine that you are a journalist and you could conduct an interview with Martin Ogle. Work in groups and come up with one journalistic question that would help you find out more about Martin Ogle. Think about who is your audience who is going to read your article or view your video interview. What would these readers/viewers be interested to know? What would you like to know about him and his business? Write down your suggestions for a question on a sheet of paper. Don t forget to come up with a fancy name for your rubric/news website, etc.! Let each group read their questions out loud. They need to explain why they think this is the most appropriate question to ask. Let the other groups imagine what Martin would answer and share that. CORE 6. REFLECTION (5 min.) You can ask the following questions to the whole class and collect several answers from volunteers. Alternatively you could ask the students to fill in their answers individually in written form in the worksheet provided: In your opinion, how does the Gaia theory relate to the systems thinking approach from Lesson 1? What is the most important thing you learned during this lesson? How could you apply the understanding from the Gaia theory in your everyday life? 7. A LOOK INTO THE FUTURE Tell the students that from next time a new section in the GREENT course will start which will be related to the impact of human activities on natural systems. Up to the end of the 18th century human activities (agriculture, construction, etc.) did not have a huge impact on the evolution of natural systems and nature was self-regulated. But, since the end of the 18th century, after what has been called the Industrial Revolution, the accumulation of dense populations in cities, technological evolution, production becoming massive and gradual population growth, the impact of human activities on the environment has started to become particularly serious. 50

7 Self-regulating mechanism of Earth In the next lesson you will take a closer look at climate change, how it affects the carbon cycle of the Earth, and what the underlying causes and the consequences are. We will also take a look at some entrepreneurs whose mission is to address climate change through their businesses. 8. HOMEWORK If you have done the first part of this activity in the Practical activity session, leave the second part of it as homework for the students. Tell the students that in order to follow up on the interview questions they just came up with, for homework they would have to review and explore all the resources on com/. They need to work in the same groups. Could they find an answer to their group s question there? Did the information on the website provoke them for new questions? Let each group post a final version of their questions list to the online platform you are using for communication with the class in between the classes (could be a Facebook group, Google Hangouts, or a special system your school uses). All members of groups need to comment on the questions and all groups need to come up with one single final list of questions. You need to moderate that process, so be sure to check online how the discussion is going. Encourage the students to actually send their questions to Martin (martin@entrepreneurialearth. com) and see if they are going to receive a response. They could describe they are taking a course on Green Entrepreneurship and that his business is one of the case studies of sustainable businesses in the lesson about Gaia Theory. 9. ADDITIONAL LINKS These are additional resources that you as a teacher can use in order to prepare for the lesson broadening your knowledge. You can also use these resources by assigning them to the students as out-of-class reading/viewing. Feedback mechanisms of the Earth : (07:59 min.). This video gives more information about how the Earth s feedback mechanisms work. In the case of climate change, the Earth responds to increasing greenhouse gas emissions by increasing the overall temperature so that more heat can be radiated back into space until the original balance is restored. Four feedback mechanisms of the Earth are discussed the ice albedo feedback (which helps keep our planet cooler, but in the case of a warming planet it amplifies this effect causing the planet to warm up even more), the water vapor-cloud feedback, atmosphere-ocean interactions and atmosphere-biota interactions. You can watch the video only until the 3:30 min. without a registration. OPTIONAL 51

8 Worksheet Self-regulating mechanism of Earth Lesson 06 In your opinion, how does the Gaia theory relate to the systems thinking approach from Lesson 1? What is the most important thing you learned during this lesson? How could you apply the understanding from the Gaia theory in your everyday life?