Systems, Matter and Energy

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Systems, Matter and Energy

• APES
• September 2005

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Miller Chapter 3Science, Systems, Matter, and
Energy

• What is a system? What is a systems approach?
• What are the components/behaviors of complex
  systems?
• Basic forms of matter and energy
• Matter and energy as a resource
• Scientific laws governing matter and energy
• Application of the laws of matter and energy to a
  sustainable society

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A Brief Note About Science Terms

• Controlled Experiment
• Single-variable analysis
• Dependent vs. Independent variables
• Experimental (treatment) vs. Control Group
• Variables to be held constant
• Hypotheses if ___, then____ or null
• Limitations of Environmental Science
• A huge number of interacting variables in the
  field
• We do not often have enough data or sufficiently
  sophisticated mathematical models to aid in our
  understanding
• Multivariable analysis gets around this somewhat
• Meaningful controlled experiments in the lab are
  limited by their applicability to real world
  scenarios
• Frontier vs. Consensus Science
• Junk science

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What is a systems approach to science?
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A Systems Approach to the World

• Environment viewed and analyzed as a set of
  complex interacting systems involving living and
  non-living components
• SYSTEMS
• Consist of interconnected components that
  function and are linked together to form
  integrated wholes
• The whole is always greater than the sum of its
  parts
• Behavior is theoretically predictable
• Is a pile of auto parts in the corner a system?
• Emphasis in EnvSci on relationships and linkages
  between constituent parts of the whole
• CAUTION! This reductive method can often make us
  lose sight of the forest amongst the trees

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System Components

• Inputs
• Matter or energy or information
• Flows or throughputs
• Of matter or energy or information
• Stores (storage areas)
• Areas where matter, energy, or information can
  accumulate for various lengths of time before
  being released
• Outputs
• Of matter or energy or info that flow out of
  system into sinks in the environment
• Boundaries or edges

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Ecosystem as an example of a system

• Biotic and abiotic factors interacting in a given
  area
• What would this be in our ecocolumn?
• Energy flows through the system Matter recycles
  within it
• Photosynthesis fixes suns energy and passes it
  on to animals?eventually released as heat that is
  radiated off into space
• Energy flows
• Carbon (matter) is also fixed from carbon
  dioxide and carbohydrates?passes through several
  organisms before reaching the atmosphere from
  whence it will again be extracted by
  photosynthesizing plants
• Cycling of carbon from one sink to another

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Types of Systems

• Open
• Exchanges matter and energy across its boundaries
  with its surroundings
• Example almost all ecosystems are open (IB
  handout fig2)
• Organisms, organ systems, cells, etc
• Closed
• Energy (but not matter) is transferred between a
  system and its surroundings
• Do not occur naturally on earth but earth itself
  comes close
• Biosphere II project attempted to simulate it
• Energy enters as sunlight departs as IR radiation
  (HEAT!)
• Isolated
• Exchanges neither matter nor energy
• Can not exist naturally with exception of whole
  universe as a system

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Properties of Complex Systems

• Open-ness
• Nested (a person is made of cells)
• Homeostasis or equilibrium
• Feedback loops (positive negative)
• Time delays (lag effects)
• Discontinuities
• Synergismsnon linear dynamics

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System Equilibrium or homeostasis

• Static Equilibrium
• No change properties remain constant over time
  condition to which natural systems can be
  compared to
• Steady-State Equilibrium
• Common to most open systems in nature
• Although there is continual input and output of
  matter and energy, the state of the system
  remains constant
• Population may go up or down but remains
  relatively constant
• Example of homeostasis in mammals within a degree
  or two of normal is a great example
• Predator prey numbers is another good example
• Stability the tendency of the system to return
  to its original equilibrium following disturbance
• As opposed to adopting a new equilibrium

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What would be considered stability in our
ecocolumn?
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How is homeostasis achieved?

• Feedback Loops
• A portion of output signal is fed back as an
  input
• Can either reinforce or slows the original change
• ExampleAn output of energy or matter is fed
  back into the system as an input that changes the
  system

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Positive and Negative Feedback Loops

• Positive Feedback Loops (think of examples)
• A change in a certain direction causes the system
  to change further in the same direction
• Accelerate the transformation in the same
  direction as the preceding results
• Results are cumulativeresults in exponential
  growth or decline
• Increases the deviation from the normdeadly in
  living systems
• Destabilize system (runaway cycle)
• Negative Feedback Loops
• A change in a certain direction causes the system
  to lessen that changecounteracts deviation from
  the norm (stabilizes system)
• Often involve time lagsproblems may build to a
  threshold and cause a fundamental change in the
  behavior of the system (Discontinuity)

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Positive and Negative Feedback
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An Example of Various Feedback Loops
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Examples of Feedback LoopsSee Gore In Class
Handout

• Global Warming and ozone depletion
• GW accentuates ozone depletion b/c it increases
  ice clouds in the stratospherewith less ozone,
  phytoplankton are able to draw down less CO2
  causing more warming
• Overuse of pesticides (pesticide resistance)
• Global Warming
• As frozen tundra thaws, methane is released.
  More methane means more warming
• As frozen tundra thaws, less light is reflected
  back into spaceless reflected light means more
  is absorbed which means more warming.

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Complex System Behaviors

• Time delays (lag effects)
• Complex systems often show time delays between
  the input of a stimulus and the response to it
• Smoker gets cancer 30 years later (Corrective
  actions may come too late!)
• Discontinuities
• Time lags allow a problem to build up slowly
  until it reaches a threshold level and causes a
  fundamental change in the behavior of the system
• Synergistic Interactions
• Deviations from additive or linear behavior

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Discontinuities

• Non linear systems can maintain dynamic
  equilibrium in the face of disruptionsbut only
  to a certain tipping point
• Then, even small shifts in their balance can
  cause critical changes that throw the system into
  disequilibrium from which it may never return to
  its original pattern
• Example
• Global warming may trigger a localized ice age
• Introduction of an exotic species totally changes
  an ecosystem

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Synergisms

• Two or more environmental processes interact in
  such a way that the outcome is not additive but
  multiplicative
• A plant with reduced sunlight is more susceptible
  to the effects of cold weather
• The toxic effect of two drugs is greater than the
  toxic effects of each individual drug

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Relationship between Complexity and Stability

• Many argue these ideas are closely coupled
• The more complex a system is, the more energy
  paths, feedback loops, and synergistic links
  there are
• A system with a multitude of links can withstand
  stress or change better than one with only a few
  components
• Railway example (single derailmentchaos)
• Biodiversity thus becomes a component of
  ecosystem stability
• Old growth forest vs Tree Plantation
• House of cards analogy

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Models of Systems

• Mathematical Models
• Describe behavior of complex systems (weather)
• Predict future behavior of complex system
• Find out how systems work
• Simulations/approximate representations of real
  system such as microcosms/macrocosms
• Can gain insight into the interactions of
  multiple variables
• Despite its usefulness, a model is no more than a
  set of hypotheses or assumptions about how we
  think a certain system works
• No better than the assumptions or the data that
  they are based upon

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Limitations of System Models

• Models are weak if
• Too many interacting variables (SYNERGISMS)
• Extrapolate from too small a sample size
• Consequences of actions have delays
• Consequences chain react (one leads to another to
  another)
• Responses vary temporally/spatially
• Not enough proper controlled experiments to get
  reliable data to model

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Matter and Energy Form and Structure

• Review of basic physics/chemistry
• Building Blocks
• Atoms (protons neutrons electrons) atomic
  pH scale, mass number elements isotopes ions
  compounds
• Covalent vs ionic bonds
• Organic vs Inorganic compounds
• Hydrocarbons chlorinated hydrocarbons (DDT)
  chlorofluorocarbons (CFC) carbohydrates
  proteins nucleic acids genes chromosomes
• Inorganic no carbon-carbon or carbon-hydrogen
  bonds
• NaCl, water, CO, CO2, SO2, NH3 etc

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Matter Quality

• High Quality
• Concentrated usually found near earths surface
• Great for use as a resource
• Aluminum can is more concentrated than aluminum
  orethats why it takes less energy to recycle!
• A cube of sugarvs. sugar dissolved in water
• Low Quality
• Dilute Deep underground or dispersed in the
  ocean or atmosphere
• Little potential for use
• E.g. gold in seawater
• Material Efficiency or Resource Productivity
• 2-6 of matter ends up providing useful goods and
  services (we need to shoot for 75-90)

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Forms of Matter (Fig 3-7)
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Energy Forms

• Capacity to do work and transfer heat
• Kinetic or potential
• Kinetic is energy that matter has because of its
  mass and speed
• Wind, streams, electricity, heat flowing from
  high to low temperature
• Potential is stored energy available for use
• Unlit stick of dynamite, water behind a dam,
  chemical energy stored in gasoline molecules, a
  bike on the top of a hill, energy stored in the
  nuclei of atoms
• Potential energy can become kinetic energy
• Potential energy is bonds of gasoline molecules
  get turned into heat, light, and mechanical
  (kinetic) energy that propels the car

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Energy Quality

• High-Quality (low entropy)
• Organized and concentrated and can perform much
  useful work
• Electricity, chemical energy of coal or gasoline,
  concentrated sunlight, uranium-235, high velocity
  wind, very high temperature heat food
• Low-Quality (high entropy)
• Disorganized and dispersed with little ability to
  do useful work
• Heat dispersed in moving molecules of matter
• Total amount of heat in Atlantic Ocean gt High
  quality energy of the oil of Saudi Arabia, yet
  too dispersed to do much with

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Energy Quality (Fig 3-9)
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Physical and Chemical Changes

• Physical Change
• No change in chemistry
• States of water
• Chemical Change
• Composition of elements or compounds altered
• Exothermic vs Endothermic
• Nuclear Changes
• Natural radioactive decay
• Unstable isotopes emit matter or radiation at a
  fixed rate
• Gamma rays (high energy electromagnetic
  radiation)
• Alpha and beta ionizing particles
• Fission (split apart nuclei?chain reaction)

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Physical Chemical Changes
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Law of Conservation of Matter There is no away

• Matter is neither created nor destroyed
• In chemical reactions, bonds are broken, atoms
  rearranged, and bonds reformed but in no way is
  matter either created nor destroyed
• Implications
• You can not make something from nothing
• We do not consume matterinstead we only use
  resources for a whilematter goes from high to
  low quality.
• Natural resources are transformed though the
  production process into something of use for
  humans?however, this product will eventually
  disintegrate, decay, fall apart, or dissipate
  into something useless
• Everything we have thrown away is still with us
  in one form or another
• We can make the environment cleaner and convert
  some potentially harmful chemicals into less
  harmful forms but we will always have to face the
  issue of where our wastes go

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Ecosystem Implications of the First Law

• The biotic and abiotic components of an ecosystem
  are linked together by matter recycling. 
• There is very little matter wasted in natural
  ecosystems.

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Laws of Energy First Law of Thermodynamics

• Basically the Law of Matter applied to energy
• 1 Energy is neither created nor destroyed but
  may be converted from one form to another
• i.e., It takes energy to get energy!
• There is no free lunch!
• Cant get something for nothing
• The quantity of energy does not change but the
  quality does
• high quality to low quality
• aka low entropy to high entropy

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Entropywhat is it?

• From the Greek word for transformation
• Entropy is a one way street of irreversible
  change
• An irreversible movement towards less ordered
  states of matter and energy
• A continual increase in the disorder of the
  universe
• Sugar cube vs. dissolved sugar
• DictionaryA measure of the unavailable energy
  in a system
• Unavailable means unavailable to do work

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Laws of Energy Second Law of Thermodynamics

• In an isolated system, the level of entropy
  (think of this as used-up-ness) or disorder
  increases in an isolated system
• In every energy transfer, some of the high
  quality energy is used and degraded to a lower
  quality form
• Energy (and matter) always go from a more useful
  to a less useful form (move towards higher
  entropy (more disorder)
• Implications of the Second Law
• We always end up with less usable energy than we
  started with (can never get out more than you put
  in!)
• In fact, you cant even break even!
• No energy exchange is perfectly efficient
• There is no perpetual motion machine
• This is why food-chains rarely have more than 5
  links
• Energy flow through an ecosystem is characterized
  by an ecological efficiency that varies from 5
  to 20.

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Putting it all together

• Although matter and energy are constant in
  quantity (1st law), they change in quality
• The measure of matter/energy quality is
  entropyThe amount of entropy is always
  increasing in an isolated system (2nd law)
• Thus, there is a flow of matter and energy from
  highly useful (low entropy) sources to less
  useful (high entropy) sinks.
• We can therefore recycle matterbut never 100
• We can not recycle energy b/c it always takes
  more energy to do the recycling than the amount
  that can be recycled
• Therefore, energy flows through, matter cycles
  within!!!
• SUMMARY OF THE SUMMARYLow entropy (high
  quality) raw materials and energy are used to
  create high entropy (low quality) waste and
  unavailable energy

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The Hourglass Metaphor
Who can explain this one?
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Energy Efficiency

• A measure of how much useful work is accomplished
  per unit input of energy
• 16 of energy in US ends up performing useful
  work
• 84 is unavoidably wasted
• 41 is unavoidably lost due to the second law of
  thermodynamics
• 43 is unnecessarily wasted by inefficiencies in
  business and society
• Remember 2nd Law Energy always goes from high
  to low quality
• Car (10 of chemical energy is converted to
  mechanical)
• Regular light bulb (5 light 95 heat)
• This applied to ecosystems is ecological
  efficiency (see ch. 4)

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Connection to EconomySee thermodynamic reading

• High-throughput economy
• High waste economy that attempts to sustain
  ever-increasing economic growth by increasing the
  flow of matter and energy resources through their
  economic system
• Exceed capacity of environment to deal with waste
  and absorb wasted heat
• In 1990, the average American's economic and
  personal activities mobilized a flow of roughly
  123 dry weight pounds of material per day...this
  includes 47lbs of fuel, 46lbs of construction
  material, 15lbs of farmland, 6lbs of forest
  products, 6lbs of industrial minerals, and 3lbs
  of metals...In sum, Americans "use" nearly 1
  million pounds of materials per person per
  year...
• Matter-recycling Economy
• Allow economic growth to continue without
  depleting natural resources or producing
  excessive pollution or environmental
  deterioration
• Buy us some time but rememberit does not allow
  for more and more people to use more and more
  resources indefinitely, even if all of them were
  perfectly recycled

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High Throughput Economy
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Lessons From Nature Low Throughput Economy