Systems

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Systems

  1. 1. Environmental Systems and Societies Interrelationships among climate, geology, soil, vegetation, and animals. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 1
  2. 2. INDEX • Type of System • Components of a system • Thermodynamics nutrient cycles • Laws of Thermodynamics • Transfer vs. transformation • Laws of Thermodynamics • Equilibria-Steady-State-Static • Feedback Mechnasim ESS/GURU/CHAPTER1 SYSTEMS & MODELS 2
  3. 3. What is ENERGY? • Energy is defined as the ability or the capacity to do work. • Energy causes things to happen around us • Energy lights our cities, powers our vehicles, and runs machinery in factories. It warms and cools our homes, cooks our food, plays our music, and gives us pictures on television. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 3
  4. 4. What is MATTER? • Matter is generally considered to be anything that has mass and volume • Example: • a car would be said to be made of matter, as it occupies space, and has mass. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 4
  5. 5. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 5
  6. 6. TYPES OF SYSTEM 1. OPEN SYSTEM 2. CLOSED SYSTEM 3. ISOLATED SYSTEM ESS/GURU/CHAPTER1 SYSTEMS & MODELS 6
  7. 7. Systems are defined by the source and ultimate destination of their matter and/or energy. 1. OPEN SYSTEM: a system in which both matter and energy are exchanged across boundaries of the system. Most natural living systems are OPEN systems. SYSTEMS & MODELS ESS/GURU/CHAPTER1 7
  8. 8. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 8
  9. 9. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 9
  10. 10. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 10
  11. 11. 2. CLOSED SYSTEM: a system in which energy is exchanged across boundaries of the system, but matter is not. Example-Aquarium & Terrarium ESS/GURU/CHAPTER1 SYSTEMS & MODELS 11
  12. 12. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 12
  13. 13. Terrarium A small enclosure or closed container in which selected living plants and sometimes small land animals, such as turtles and lizards, are kept and observed. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 13
  14. 14. 3. ISOLATED SYSTEM: a system in which neither energy nor matter is exchanged with its envioronemt.Do not exist naturally NO SUCH SYSTEM EXISTS!!! ESS/GURU/CHAPTER1 SYSTEMS & MODELS 14
  15. 15. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 15
  16. 16. CLOSED SYSTEM CLOSED SYSTEM OPEN SYSTEM OPEN SYSTEM CLOSED SYSTEM ESS/GURU/CHAPTER1 SYSTEMS & MODELS 16
  17. 17. Components of a system: 1. Inputs such as energy or matter. Calories Protein ESS/GURU/CHAPTER1 SYSTEMS & MODELS 17
  18. 18. 2. Flows of matter or energy within the systems at certain rates. Calories Protein ESS/GURU/CHAPTER1 Calories Protein SYSTEMS & MODELS 18
  19. 19. 3.Outputs of certain forms of matter or energy that flow out of the system into sinks in the environment. WasteHeat Calories Protein ESS/GURU/CHAPTER1 SYSTEMS & MODELS WasteMatt er 19
  20. 20. 4. Storage areas in which energy or matter can accumulate for various lengths of time before being released. Calories Protein ESS/GURU/CHAPTER1 SYSTEMS & MODELS 20
  21. 21. RECAP • • • • What is open system? Example What is closed system? Example What is Isolated system? Example Components of a system ESS/GURU/CHAPTER1 SYSTEMS & MODELS 21
  22. 22. Inputs and Outputs ESS/GURU/CHAPTER1 SYSTEMS & MODELS 22
  23. 23. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 23
  24. 24. energy input from sun PHOTOSYNTHESIS (plants, other producers) nutrient cycling RESPIRATION (hetero & autos, decomposers) energy ESS/GURU/CHAPTER1 output (mainly heat) SYSTEMS & MODELS 24
  25. 25. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 25
  26. 26. Thermodynamics nutrient cycles ESS/GURU/CHAPTER1 SYSTEMS & MODELS 26
  27. 27. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 27
  28. 28. Laws of Thermodynamics • The study of thermodynamics is about energy flow in natural systems • The Laws of Thermodynamics describe what is known about energy transformations in our universe ESS/GURU/CHAPTER1 SYSTEMS & MODELS 28
  29. 29. Two basic processes must occur in an ecosystem: 1. A cycling of chemical elements. 2. Flow of energy. Energy flows through systems while materials circulate around systems. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 29
  30. 30. TRANSFORMATTION OF ENERGY TRANSFERS OF ENERGY ESS/GURU/CHAPTER1 SYSTEMS & MODELS 30
  31. 31. Cycling of Chemical Elements TRANSFERS: normally flow through a system and involve a change in location. TRANSFORMATIONS: lead to an interaction within a system in the formation of a new end product, or involve a change of state. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 31
  32. 32. Transfer vs. transformation • Transfer involves a change in location – e.g. water falling as rain, running off the land into a river then to the sea • Transformation involves a change in state – e.g. evaporation of water from a lake into the atmosphere • Energy examplesSYSTEMS & MODELS ESS/GURU/CHAPTER1 32
  33. 33. TRANSFERS OF ENER ESS/GURU/CHAPTER1 SYSTEMS & MODELS 33
  34. 34. TRANSFERS OF ENERGY ESS/GURU/CHAPTER1 SYSTEMS & MODELS 34
  35. 35. ENERGY TRANSFORMATIONS ESS/GURU/CHAPTER1 SYSTEMS & MODELS 35
  36. 36. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 36
  37. 37. Describe Transfer and Transformation • Transfer - just a movement from one place to another ….water mountain to ocean.. • Transformation - actual change of state or material -- liquid water/evaporates… CO2 to sugars/starch in plant . ESS/GURU/CHAPTER1 SYSTEMS & MODELS 37
  38. 38. Distinguish flows and storage • Flows are input and output • exmple….input food -- output wastes energy • Storage -- usually a transformation into a form of matter/energy that can be used later…… ESS/GURU/CHAPTER1 SYSTEMS & MODELS 38
  39. 39. What is Thermodynamics? 1. Thermodynamics is the study of the energy transformations that occur in a system. 2. It is the study of the flow of energy through nature. 3. Within a system energy cannot be re-used. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 39
  40. 40. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 40
  41. 41. • Two laws • First Law of Thermodynamics • Second Law of Thermodynamics ESS/GURU/CHAPTER1 SYSTEMS & MODELS 41
  42. 42. 1st Law of Thermodynamics •States that energy can be transferred and transformed, but it CANNOT be created nor destroyed. •Law of Conservation of Energy. •Energy of the universe is constant. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 42
  43. 43. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 43
  44. 44. First Law of Thermodynamics ENERGY 2 ENERGY 1 PROCESS (WORK) ENERGY 3 ESS/GURU/CHAPTER1 SYSTEMS & MODELS 44
  45. 45. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 45
  46. 46. Photosynthesis: an example of the First Law of Thermodynamics: Energy Transformation ESS/GURU/CHAPTER1 SYSTEMS & MODELS 46
  47. 47. Photosynthesis and the First Law of Thermodynamics Heat Energy Light Energy Photosynthesis Chemical Energy ESS/GURU/CHAPTER1 SYSTEMS & MODELS 47
  48. 48. ESS/GURU/CHAPTER1 SYSTEMS MODELS Thermal equilibrium = inputs equal&outputs over a long period of 48 time.
  49. 49. Energy at one level must come from previous level Sun Producers (rooted plants) Producers (phytoplankton) Primary consumers (zooplankton) Secondary consumers (fish) Dissolved chemicals ESS/GURU/CHAPTER1 Tertiary consumers (turtles) Sediment SYSTEMS & MODELS Decomposers (bacteria and fungi) 49
  50. 50. Answer this……………….. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 50
  51. 51. Using the first law of thermodynamics explain why the energy pyramid is always pyramid shaped (bottom bigger than ESS/GURU/CHAPTER1 SYSTEMS & MODELS 51 top)
  52. 52. WORLDS TALLEST FLOWER ESS/GURU/CHAPTER1 SYSTEMS & MODELS 52
  53. 53. titan arum ESS/GURU/CHAPTER1 SYSTEMS & MODELS 53
  54. 54. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 54
  55. 55. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 55
  56. 56. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 56
  57. 57. • The titan arum or Amorphophallus titanum s a flowering plant with the largest unbranched inflorescence in the world. • The titan arum's inflorescence can reach over 3 metres (10 ft) in circumference. • The leaf structure can reach up to 6 metres (20 ft) tall and 5 metres (16 ft) across • The corm is the largest known, weighing around 50 kilograms (110 ESS/GURU/CHAPTER1 SYSTEMS & MODELS 57
  58. 58. 2nd Law of Thermodynamics 1. The Second Law is the Law of Entropy(disorder, randomness or chaos). 2. It is essential state that as energy is transformed from one from to another the conversion is never 100% efficient and therefore energy is always lost to that system 3. Every energy transformation or transfer results in an increase in the disorder of the universe ESS/GURU/CHAPTER1 SYSTEMS & MODELS 58
  59. 59. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 59
  60. 60. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 60
  61. 61. The Second Law of Thermodynamics can also be stated in the following way: • • • In any spontaneous process the energy transformation is not 100 % efficient, part of it is lost (dissipated) as heat which, can not be used to do work (within the system) to fight against entropy. In fact, for most ecosystems, processes are on average only 10% efficient (10% Principle), this means that for every energy passage (transformation) 90% is lost in the form of heat energy, only 10% passes to the next element in the system. Most biological processes are very inefficient in their transformation of energy which is lost as heat. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 61
  62. 62. What results from the second law of Thermodynamic s? ESS/GURU/CHAPTER1 SYSTEMS & MODELS 62
  63. 63. Second Law of Thermodynamics ESS/GURU/CHAPTER1 SYSTEMS & MODELS 63
  64. 64. •Any conversion is less than 100% efficient and therefore some energy is lost or wasted. •Usually this energy is lost in the form of HEAT (= random energy of molecular movement). We usually summarize it as respiration. (photosynthesis) Waste heat ESS/GURU/CHAPTER1 Mechanical energy Chemical energy (food) Chemical energy Solar energy Waste heat SYSTEMS & MODELS (moving, thinking, living) Waste heat Waste heat 64
  65. 65. Only 25% of chemical “E” stored in gasoline is transformed in to motion of the car and 75% is lost as heat!! ESS/GURU/CHAPTER1 SYSTEMS & MODELS 65
  66. 66. RECAP • • • • • • • • • • • What is a SYSTEM? Types of system What is open system Closed system Isolated system What is thermo dynamics? What is First law of thermodynamics? What is second law of thermodynamics? What is transfer of energy? What is transformation of energy? Tallest flower ESS/GURU/CHAPTER1 SYSTEMS & MODELS 66
  67. 67. The Second Law of Thermodynamics in numbers: The 10% Law For most ecological process, theamount of energy that is passed from one trophic level to the next is on average 10%. Heat 900 J Energy 1 Process 3 1000 J J Heat 90 J Heat 9J Process 1 Process 2 100 J 10 J J = Joule SI Unit of Energy & MODELS SYSTEMS ESS/GURU/CHAPTER1 1 67
  68. 68. Without adding energy to a system, the system will break down . ESS/GURU/CHAPTER1 SYSTEMS & MODELS 68
  69. 69. Primary Producers and the 2nd law of Thermodynamics (Output) (Output) (Output) ESS/GURU/CHAPTER1 SYSTEMS & MODELS 69
  70. 70. Consumers and the 2nd law of Thermodynamics How efficient is the cow in the use of the food it takes daily? Respiration 2000 kJ.day-1 10% for growth 565 kJ.day-1 Urine and Faeces 2850 kJ.day1 Food Intake ESS/GURU/CHAPTER1 SYSTEMS & MODELS 70
  71. 71. The Ecosystem and the 2nd law of Thermodynamics Heat Heat Heat Heat Heat ESS/GURU/CHAPTER1 SYSTEMS & MODELS 71
  72. 72. Why both the laws are important in ecosystem or environment? • Both the laws are important because when analyzing the energy transfers in an ecosystem and living organism is general ESS/GURU/CHAPTER1 SYSTEMS & MODELS 72
  73. 73. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 73
  74. 74. RECAP • What is First Law of Thermodynamics • What is Second Law of Thermodynamics? • What is EQUILIBRIUM? • Three types of equilibrium ESS/GURU/CHAPTER1 SYSTEMS & MODELS 74
  75. 75. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 75
  76. 76. What is Equilibrium • Equilibrium is the tendency of the system to return to an original state following disturbance, a state of balance exists among the components of that system. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 76
  77. 77. 3 TYPES 1. STEADY –STATE EQUILIBRIUM 2. STATIC EQUILIBRIUM 3. STABLE & UNSTABLE EQUILIBRIUM ESS/GURU/CHAPTER1 SYSTEMS & MODELS 77
  78. 78. STEADY –STATE EQUILIBRIUM EXAMPLE death birth If these birth & death rates are equal there is no net change In population size ESS/GURU/CHAPTER1 SYSTEMS & MODELS 78
  79. 79. QUESTION WHERE YOU CAN SEE STEADY –STATE EQUILIBRIUM IN ECOSYSTEM ESS/GURU/CHAPTER1 SYSTEMS & MODELS 79
  80. 80. Food chain & Food web are the example of Steady –State Equilibrium ESS/GURU/CHAPTER1 SYSTEMS & MODELS 80
  81. 81. Steady –State Equilibrium • A Steady –state equilibrium is a characteristic of open system where there are continuous inputs and outputs of energy and matter, but the system as a whole remains in a more or less constant state ESS/GURU/CHAPTER1 SYSTEMS & MODELS 81
  82. 82. Rate of water entering = Rate of water leaving Hence the level of water is constant ESS/GURU/CHAPTER1 SYSTEMS & MODELS 82
  83. 83. STATIC EQUILIBRIUM • Static Equilibrium in which there is no change over time • The force within the system are in balance, and the components remain unchanged in their relationship ESS/GURU/CHAPTER1 SYSTEMS & MODELS 83
  84. 84. let us consider two children sitting on a seesaw. At balance point (i.e., the equilibrium position) no movement of children on the seesaw occurs. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 84
  85. 85. QUESTION WHERE YOU CAN SEE STATIC EQUILIBRIUM IN ECOSYSTEM ESS/GURU/CHAPTER1 SYSTEMS & MODELS 85
  86. 86. • Most non living system are in Static Equilibrium ESS/GURU/CHAPTER1 SYSTEMS & MODELS 86
  87. 87. STABLE & UNSTABLE EQUILIBRIUM • In a stable equilibrium the system tends to return to the same equilibrium after a disturbance • In an unstable equilibrium the system returns to a new equilibrium after disturbance ESS/GURU/CHAPTER1 SYSTEMS & MODELS 87
  88. 88. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 88
  89. 89. FOREST FIRE -DISTURBANCE AFTER DISTURBANCE ESS/GURU/CHAPTER1 SYSTEMS & MODELS 89
  90. 90. RECAP • What is First Law of Thermodynamics • What is Second Law of Thermodynamics? • What is EQUILIBRIUM? • Three types of equilibrium ESS/GURU/CHAPTER1 SYSTEMS & MODELS 90
  91. 91. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 91
  92. 92. Rafflesia Found in the Indonesian rain forest ESS/GURU/CHAPTER1 SYSTEMS & MODELS 92
  93. 93. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 93
  94. 94. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 94
  95. 95. RECAP 1. What is Equilibrium 2. STEADY –STATE EQUILIBRIUM 3. STATIC EQUILIBRIUM 4. STABLE & UNSTABLE EQUILIBRIUM ESS/GURU/CHAPTER1 SYSTEMS & MODELS 95
  96. 96. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 96
  97. 97. What is FEEDBACK? • Systems are continually affected by information from outside & inside the system is called as FEEDBACK • Feedbacks can be positive or negative ESS/GURU/CHAPTER1 SYSTEMS & MODELS 97
  98. 98. The sense of cold is the information, putting on clothes or heating up is the reaction cold clothes heating up ESS/GURU/CHAPTER1 SYSTEMS & MODELS 98
  99. 99. POSTIVE FEEDBACK Respond Positively in the class Teacher is successful Showing interest ESS/GURU/CHAPTER1 SYSTEMS & MODELS 99
  100. 100. NEGATIVE FEEDBACK Respond negatively in the class Methodology is not appropriate Showing distraction ESS/GURU/CHAPTER1 SYSTEMS & MODELS 100
  101. 101. What is feedback loop? • Natural system act in exactly the same way. • The information starts a reaction which in turn input more information which may starts another reaction. • This is feedback loop ESS/GURU/CHAPTER1 SYSTEMS & MODELS 101
  102. 102. Positive and Negative Feedback ESS/GURU/CHAPTER1 SYSTEMS & MODELS 102
  103. 103. What is FEEDBACK SYSTEM? • The way that living systems and non living systems self-regulate or maintain homeostasis (the maintenance of a steady state in an organism, ecosystem or biosphere) is through feedback systems is called as FEEDBACK SYSTEM ESS/GURU/CHAPTER1 SYSTEMS & MODELS 103
  104. 104. Negative feedback systems Walking in hot sun, temperature rises ONE ACTION IS INCREASING Body will lose heat ONE ACTION IS DECREASING ESS/GURU/CHAPTER1 SYSTEMS & MODELS 104
  105. 105. Negative feedback systems • Negative feedback systems include a sequence of events that will cause an effect that is in the opposite direction to the original stimulus and thereby brings the system back to its equilibrium position. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 105
  106. 106. Example of Negative Feedback • Predator/prey relationships ESS/GURU/CHAPTER1 SYSTEMS & MODELS 106
  107. 107. • Predator/prey relationships are usually controlled by negative feedback where: The increase in prey  increase in predator decrease in prey decrease in predator increase in prey---and so on in a cyclical manner. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 107
  108. 108. The classic study in Northern Canada between the Wild Cat and the hare populations is famous for its regular 11 year cycle of rising and falling populations. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 108
  109. 109. Negative feedback • Predator Prey is a classic Example – Snowshoe hare population increases – More food for Lynx  Lynx population increases – Increased predation on hares  hare population declines – Less food for Lynx  Lynx population declines – Less predation  Increase in hare population ESS/GURU/CHAPTER1 SYSTEMS & MODELS 109
  110. 110. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 110
  111. 111. ANSWER THIS • IDENTIFY THIS BIRD ESS/GURU/CHAPTER1 SYSTEMS & MODELS 111
  112. 112. SARUS CRANE at a height of up to 1.8 m (5.9 ft) ESS/GURU/CHAPTER1 SYSTEMS & MODELS 112
  113. 113. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 113
  114. 114. SEPTEMBER FORMATIVE & SUMMATIVE • Formative- Worksheet • Marks-30 • • • • Summative –Test Date-19.09.2012 Marks-45 Times:1 hour ESS/GURU/CHAPTER1 SYSTEMS & MODELS 114
  115. 115. POSTIVE FEEDBACK ESS/GURU/CHAPTER1 SYSTEMS & MODELS 115
  116. 116. poverty Positive feedback Poor standards of education Absence of family planning ESS/GURU/CHAPTER1 SYSTEMS & MODELS 116
  117. 117. Positive feedback • • • A runaway cycle – often called vicious cycles A change in a certain direction provides output that further increases that change Change leads to increasing change – it accelerates deviation Example: Global warming 1. Temperature increases  Ice caps melt 2. Less Ice cap surface area  Less sunlight is reflected away from earth (albedo) 3. More light hits dark ocean and heat is trapped 4. Further temperature increase  Further melting of the ice ESS/GURU/CHAPTER1 SYSTEMS & MODELS 117
  118. 118. Positive feedback • Positive feedback includes a sequence of events that will cause a change in the same direction as the stimulus and thereby augments the change, moving the state of the system even further from the equilibrium point. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 118
  119. 119. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 119
  120. 120. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 120
  121. 121. Solar radiation Energy in = Energy out Reflected by atmosphere (34%) Radiated by atmosphere as heat (66%) UV radiation Absorbed by ozone Lower stratosphere (ozone layer) Visible Greenhouse light Troposphere effect Heat Absorbed by the earth Heat radiated by the earth Earth ESS/GURU/CHAPTER1 SYSTEMS & MODELS 121
  122. 122. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 122
  123. 123. Most systems change by a combination of positive and negative feedback processes ESS/GURU/CHAPTER1 SYSTEMS & MODELS 123
  124. 124. I-POSTIVE FEEDBACK II-NEGATIVE III-NEGATIVE IV-POSTIVE Which of the populations show positive feedback? ESS/GURU/CHAPTER1 SYSTEMS show 124 Which of the populations & MODELS negative feedback?
  125. 125. WHICH IS POSTIVE & NEGATIVE • If a pond ecosystem became polluted with nitrates, washed off agricultural land by surface runoff, algae would rapidly grow in the pond. • The amount of dissolved oxygen in the water would decrease, killing the fish. • The decomposers that would increase due to the dead fish would further decrease the amount of dissolved oxygen and so on... ESS/GURU/CHAPTER1 • A good supply of grass for rabbits to eat will attract more rabbits to the area, which puts pressure on the grass, so it dies back, so the decreased food supply leads to a decrease in population because of death or out migration, which takes away the pressure on the grass, which leads to more growth and a good supply of food which leads to a more rabbits attracted to the area which puts pressure on the grass and so on and on.... SYSTEMS & MODELS 125
  126. 126. End result? Equilibrium…Recap • A sort of equalization or end point • Steady state equilibrium  constant changes in all directions maintain a constant state (no net change) – common to most open systems in nature • Static equilibrium  No change at all – condition to which most natural systems can be compared but this does not exist • Long term changes in equilibrium point do occur (evolution, succession) • Equilibrium is stable (systems tend to return to the original equilibrium after disturbances) ESS/GURU/CHAPTER1 SYSTEMS & MODELS 126
  127. 127. Equilibrium generally maintained by negative feedback – inputs should equal outputs ESS/GURU/CHAPTER1 SYSTEMS & MODELS 127
  128. 128. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 128
  129. 129. You should be able to create a system model. Observe the next two society examples and create a model including input, flows, stores and output ESS/GURU/CHAPTER1 SYSTEMS & MODELS 129
  130. 130. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 130
  131. 131. High Throughput System Model ESS/GURU/CHAPTER1 SYSTEMS & MODELS 131
  132. 132. Inputs (from environment) System Throughputs Output (intro environment) Low-quality heat energy High-quality energy Unsustainable high-waste economy Waste matter and pollution Matter ESS/GURU/CHAPTER1 SYSTEMS & MODELS 132
  133. 133. Low Throughput System Model ESS/GURU/CHAPTER1 SYSTEMS & MODELS 133
  134. 134. Inputs (from environment) High-quality energy Matter System Throughputs Outputs (from environment) Low-quality energy (heat) Sustainable low-waste economy Pollution prevention by reducing matter throughput Pollution control by cleaning up some pollutants Recycle and reuse Matter output Waste matter and pollution Matter Feedback Energy Feedback ESS/GURU/CHAPTER1 SYSTEMS & MODELS 134
  135. 135. Easter Island What are the statues and where are the trees? A c ESS/GURU/CHAPTER1 SYSTEMS & MODELS 135 Study in unsustainable growth practices.
  136. 136. Evaluating Models • Used when we can’t accurately measure the real event • Models are hard with the environment because there are so many interacting variables – but nothing else could do better • Allows us to predict likelihood of events • But… • They are approximations • They may yield very different results from each other or actual events • There are always unanticipated possibilities… ESS/GURU/CHAPTER1 SYSTEMS & MODELS 136
  137. 137. Anticipating Environmental Surprises • Remember any action we take has multiple unforseen consequences • Discontinuities = Abrupt shifts occur in previously stable systems once a threshold is crossed • Synergistic interactions = 2 factors combine to produce greater effects than they do alone • Unpredictable or chaotic events = hurricanes, earthquakes, climate shifts • http://www.nhc.noaa.gov/archive/2008/FAY_gra phics.shtml ESS/GURU/CHAPTER1 SYSTEMS & MODELS 137
  138. 138. What can we do? • Develop more complex models for systems • Increase research on environmental thresholds for better predictive power • Formulate possible scenarios and solutions ahead of time ESS/GURU/CHAPTER1 SYSTEMS & MODELS 138
  139. 139. Define objectives Systems Measurement Data Analysis Identify and inventory variables Obtain baseline data on variables Make statistical analysis of relationships among variables Determine significant interactions © 2004 Brooks/Cole – Thomson Learning System Modeling Construct mathematical model describing interactions among variables System Simulation Run the model on a computer, with values entered for different variables System ESS/GURU/CHAPTER1 Optimization Evaluate best ways to achieve objectives SYSTEMS & MODELS 139
  140. 140. Other systems examples ESS/GURU/CHAPTER1 SYSTEMS & MODELS 140
  141. 141. Uranium mining (95%) Uranium 100% Uranium processing and transportation (57%) 95% Power Transmission plant of electricity (85%) (31%) Waste heat Waste heat 14% 17% 54% Waste heat Resistance heating (100%) 14% Waste heat Electricity from Nuclear Power Plant Sunlight 100% 90% Waste heat ESS/GURU/CHAPTER1 Passive Solar SYSTEMS & MODELS Energy Production 141
  142. 142. sun EARTH Economic Systems Natural Capital Air; water, land, soil, biodiversity, minerals, raw materials, energy resources, and dilution, degradation, and recycling services Production Heat Depletion of nonrenewable resources Degradation and depletion of renewable resources used faster than replenished Consumption Pollution and waste from overloading nature’s waste disposal and recycling systems ESS/GURU/CHAPTER1 Recycling and reuse SYSTEMS & MODELS Economics & Earth 142
  143. 143. Energy Inputs System Outputs 9% 7% 41% 84% U.S. economy and lifestyles 43% 8% 4% 4% Nonrenewable fossil fuels Nonrenewable nuclear Useful energy Petrochemicals Unavoidable energy Hydropower, geothermal, waste wind, solar ESS/GURU/CHAPTER1 SYSTEMS & MODELS Unnecessary energy Biomass waste 143

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