1. SYSTEMS AND CHANGE Chapter 3 Environmental Science Part One Mr. Thompson Environmental Science Systems and Change 1

2. LEARNING OBJECTIVES Why solutions to many environmental problems involve the study of systems and rates of change. How positive and negative feedback operate in a system. Mr. Thompson Environmental Science Systems and Change 2 3. LEARNING OBJECTIVES CONTINUED What are the implications of exponential growth and doubling time. That natural disturbances and changes in systems such as forests, rivers, and coral reefs are important to their continued existence. Mr. Thompson Environmental Science Systems and Change 3 4. LEARNING OBJECTIVES CONTINUED What an ecosystem is and why sustained life on Earth is a characteristic of ecosystems. What the Gaia hypothesis is and how life on Earth has affected the Earth itself. What the principle of uniformitarianism is and how it can be used to anticipate future changes. Mr. Thompson Environmental Science Systems and Change 4 5. LEARNING OBJECTIVES CONTINUED Why the principle of environmental unity is important in studying environmental problems. How human activities amplify the effects of natural disasters. Mr. Thompson Environmental Science Systems and Change 5 6. UNDERSTANDING SYSTEMS How systems interact with each other. System a set of components or parts that function together to act as a whole. i.e. your body is a system, your bedroom is a system. The Earth is a system. Mr. Thompson Environmental Science Systems and Change 6 7. TYPES OF SYSTEMS Open systems is not generally contained within boundaries and some energy or material (solid, liquid or gas) moves into or out of the system. i.e. the Ocean is an open system. Closed systems no such movements take place. Earth is a closed system with regard to material. Systems respond to inputs and have outputs. Your body is a complex system. Mr. Thompson Environmental Science Systems and Change 7 8. FEEDBACK Feedback occurs when the output of the system also serves as an input and leads to further changes in the system. i.e. human temperature regulation. If you go out in the sun and get hot, the increase in temperature affects your sensory perceptions (input). If you stay in the sun, your body responds physiologically. You are cooled by evaporating water when you sweat. The cooling is output and also input to your sensory perceptions. Mr. Thompson Environmental Science Systems and Change 8 9. HOW EARTH WORKS AS A SET OF INTERCONNECTED SYSTEMS Mr. Thompson Environmental Science Systems and Change 9 10. HUMANS AFFECT THE EARTH SYSTEM Mr. Thompson Environmental Science Systems and Change 10 How we affect our environment is important. Human activities increase and decrease the magnitude and frequency of some natural Earth processes. As human population increases a parallel increase in the extinction of species has occurred. 11. HUMANS CHANGE THE EARTH Mr. Thompson Environmental Science Systems and Change 11 12. PART TWO Mr. Thompson Environmental Science Systems and Change 12 13. DIY BIOSPHERE Mr. Thompson Environmental Science Systems and Change 13 14. ECOSYSTEMS A community of organisms and its local nonliving environment in which matter (chemical elements) cycles and energy flows. Mr. Thompson Environmental Science Systems and Change 14 15. GAIA HYPOTHESIS Greek Goddess Mother Earth John Lovelock Life manipulates the environment for the maintenance of life. Mr. Thompson Environmental Science Systems and Change 15 16. THE GAIA HYPOTHESIS Mr. Thompson Environmental Science Systems and Change 16 17. STAGGERING AMOUNTS OF ENVIRONMENTAL CHANGE In 10 years since launch, Europe's Earth observation satellite data documents changes in ozone, pollution, effects of natural disasters and more. Mr. Thompson Environmental Science Systems and Change 17 18. HUMAN AMPLIFICATION OF ENVIRONMENTAL CHANGE Natural change can rearrange the landscape almost overnight by earthquake, flood, volcanic eruption or hurricane. Catastrophe an event which damages people, property and society. Mr. Thompson Environmental Science Systems and Change 18 19. HUMAN ACTIVITIES POTENTIALLY IMPACT NATURAL DISASTERS People had removed one-half of the forest of Honduras. In addition, an 11,000 km2 fire had damaged the the region prior to the hurricane. Hillsides stripped of vegetation washed away during the hurricane. Mr. Thompson Environmental Science Systems and Change 19 20. GLOBAL WARMING Most changes brought on by human activity involve rather slow processes with cumulative effects. Mr. Thompson Environmental Science Systems and Change 20 21. LESSONS LEARNED Land rehabilitation Sustainable development Maintenance healthy ecosystems Mr. Thompson Environmental Science Systems and Change 21