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1. Topic 1: Systems
• SYSTEM: an assemblage of parts and their relationship forming a
functioning entirety or whole.

2. Topic 1: Systems
• 1970’s James Lovelock proposes the GAIA
hypothesis
• The planet acts like a single biological
being made up of individual and
interconnected units
• A SYSTEM

3. Physical Climate System
Atmospheric Physics/Dynamics Climate
Sun Change
Terrestrial
Ocean Dynamics
Strotspheric Chemistry/ energy/moisture
External Forcing
Human Activities
Dynamics
Global
Moisture Soil CO2
Land
Marine Terrestrial
Use
Volcanoes
Biogeochemistry Ecosystems
Tropospheric chemistry CO2
Biogeochemical System Polluntants

4. Topic 1: Systems
• Systems involve: Inputs of Water, Carbon Dioxide
and Sunlight
Light energy is trapped
by the chlorophyll
inside the chloroplasts
• Inputs
• Outputs
• Processes
Oxygen is realesed Energy is released, splitting
to the atmosphere water into hydrogen and
oxygen
The hydrogen combines with
carbon dioxide to make glucose

5. Topic 1: Systems
• Individual systems can be sub-units of bigger systems

6. Topic 1: Systems
• Individual systems can be sub-units of bigger systems
Inputs of Water, Carbon Dioxide
Light energy is trapped
and Sunlight
by the chlorophyll
inside the chloroplasts
• A food chain includes photosynthesising plants
Oxygen is realesed Energy is released, splitting
to the atmosphere water into hydrogen and
oxygen
The hydrogen combines with
carbon dioxide to make glucose

7. Topic 1: Systems
• All systems include inputs, processes and outputs

8. Topic 1: Systems
• All systems include inputs, processes and outputs
Input Output
Process

9. Topic 1: Systems
• All systems include inputs, processes and outputs
Input Output Input Output Input Output
Process Process Process

10. Topic 1: Systems
1.1.2: Types of System

11. Topic 1: Systems
1.1.2: Types of System
• Open Systems

12. Topic 1: Systems
1.1.2: Types of System
• Open Systems
• Closed Systems

13. Topic 1: Systems
1.1.2: Types of System
• Open Systems
• Closed Systems
• Isolated Systems

14. Topic 1: Systems
1.1.2: Types of System
Open Systems
• exchange matter and energy with its surroundings.
Atmospheric Carbon dioxide
Combustion
Respiration
Photosynthesis
Higher Consumers
Fossil fuels and Wood
Primary
Consumers
Fossils and Detrivores Detritus
Sediments

15. Topic 1: Systems
1.1.2: Types of System
Closed Systems
• exchange energy but not matter.

16. Topic 1: Systems
1.1.2: Types of System
Light Energy
Closed Systems From the Sun
• exchange energy but not matter.

17. Topic 1: Systems
1.1.2: Types of System
Light Energy
Closed Systems From the Sun
• exchange energy but not matter.
Long wave energy
(heat) returned
to space

18. Topic 1: Systems
1.1.2: Types of System
Closed Systems
• Biosphere 2

19. Topic 1: Systems
1.1.2: Types of System
Isolated Systems
• An isolated system exchanges
neither matter nor energy.
• Isolated systems do not
exist naturally
• Possible to think of the
entire Universe as an
isolated system

20. Topic 1: Systems
1.1.3: Energy in Systems
Energy in all systems is
subject to the Laws of
Thermodynamics

21. Topic 1: Systems
1.1.3: Energy in Systems
The First Law:
• Energy is neither created
nor destroyed..
• Energy can only change
from one form to another
• Often called: The Law
of Conservation of
energy

22. Topic 1: Systems
1.1.3: Energy in Systems
The First Law:
• Energy is neither created Incoming solar radiation (light energy) is trapped by plants and
converted to sugars (stored chemical energy)
nor destroyed..
• Energy can only change
from one form to another
• Often called: The Law
of Conservation of
energy

23. Topic 1: Systems
1.1.3: Energy in Systems
The First Law:
• Energy is neither created Consumers (herbivores) eat the plants (producers) and the stored chemical
energy gets passed up the food chain
nor destroyed..
• Energy can only change
from one form to another
• Often called: The Law
of Conservation of
energy

24. Topic 1: Systems
1.1.3: Energy in Systems
The First Law:
• Energy is neither created Consumers (carnivores) eat other consumers (herbivores) and the
stored chemical energy gets passed up the food chain again
nor destroyed..
• Energy can only change
from one form to another
• Often called: The Law
of Conservation of
energy

25. Topic 1: Systems
1.1.3: Energy in Systems
The First Law:
• Energy is neither created No energy has been created or destroyed in the food chain it has only
nor destroyed.. moved or changed form
• Energy can only change
from one form to another
• Often called: The Law
of Conservation of
energy

26. Topic 1: Systems
1.1.3: Energy in Systems
The First Law:
• Energy is neither created
nor destroyed..
• Energy can only change
from one form to another
• Often called: The Law
of Conservation of
energy

27. Topic 1: Systems
1.1.3: Energy in Systems
The First Law:
• Energy is neither created
nor destroyed..
• Of the sunlight falling on
Earth not all of it is used for
photosynthesis.

28. Topic 1: Systems
1.1.3: Energy in Systems
The Second Law:
• The entropy of an isolated
system not in equilibrium
will tend to increase over
time
• Energy conversions are
never efficient and the
more conversions in a
system the greater the
total inefficiency

29. Topic 1: Systems
1.1.3: Energy in Systems
The Second Law:
• The entropy of an isolated
system not in equilibrium
will tend to increase over
time
• Energy conversions are
never efficient and the
more conversions in a
system the greater the
total inefficiency

30. Topic 1: Systems
1.1.3: Energy in Systems
The Second Law:
• The entropy of an isolated
system not in equilibrium
will tend to increase over Heat generated
during work
time e.g. respiration
• Energy conversions are
never efficient and the
more conversions in a
system the greater the
total inefficiency

31. Topic 1: Systems
1.1.3: Energy in Systems
The Second Law:
• The entropy of an isolated
system not in equilibrium
will tend to increase over Heat generated
during work
time e.g. respiration
• Energy conversions are
never efficient and the
more conversions in a
system the greater the
total inefficiency

32. Topic 1: Systems
1.1.3: Energy in Systems
The Second Law:
• The entropy of an isolated
system not in equilibrium
will tend to increase over Heat generated Heat generated
during work during work
time e.g. respiration e.g. respiration
• Energy conversions are
never efficient and the
more conversions in a
system the greater the
total inefficiency

33. Topic 1: Systems
1.1.3: Energy in Systems
The Second Law:
• The entropy of an isolated
system not in equilibrium
will tend to increase over Heat generated Heat generated
during work during work
time e.g. respiration e.g. respiration
• Energy conversions are
never efficient and the
more conversions in a
system the greater the
total inefficiency

34. Topic 1: Systems
1.1.3: Energy in Systems
The Second Law:
• The entropy of an isolated
system not in equilibrium
will tend to increase over Heat generated Heat generated Heat generated
during work during work during work
time e.g. respiration e.g. respiration e.g. respiration
• Energy conversions are
never efficient and the
more conversions in a
system the greater the
total inefficiency

35. Topic 1: Systems
1.1.3: Energy in Systems
Heat
The Second Law:
• Can be thought of as a
Input Energy Useful Energy
simple word equation
Work
• Energy = Work + Heat (and
other waste products)
• Or the spreading out of Conversion
energy process

36. Topic 1: Systems
1.1.4: Equilibria
Open systems tend to exist in a state of balance

37. Topic 1: Systems
1.1.4: Equilibria
Two types of Equilibrium
•Static
•Dynamic

38. Topic 1: Systems
1.1.4: Equilibria
•Static:
Where components of the
system remain constant
over a long period of time

39. Topic 1: Systems
1.1.4: Equilibria 80
•“Dynamic”: Number of pelts (1000s) 60
Difficult concept
40
A system is in a steady state
because the inputs and
20
outputs that affect it
approximately balance
over a long period of time 0
1900 1905 1910 1915 1920
Year
Snowshoe Hare Lynx

40. Topic 1: Systems
1.1.5: Feedback
A system are continually
affected by and react to
information (stimuli)
The final outcome of the
process is governed by
feedback
•Negative
•Positive

41. Topic 1: Systems
1.1.5: Feedback
Negative feedback

42. Topic 1: Systems
1.1.5: Feedback
80
Negative feedback
Number of pelts (1000s)
• tends to damp down, 60
neutralize or counteract any
deviation from an equilibrium,
40
and promotes stability.
20
0
1900 1905 1910 1915 1920
Year
Snowshoe Hare Lynx

43. Topic 1: Systems
1.1.5: Feedback
80
Negative feedback
Number of pelts (1000s)
• tends to damp down, 60
neutralize or counteract any
deviation from an equilibrium,
40
and promotes stability.
20
0
1900 1905 1910 1915 1920
Year
Snowshoe Hare Lynx

44. Topic 1: Systems
1.1.5: Feedback
80
Negative feedback
Number of pelts (1000s)
• tends to damp down, 60
neutralize or counteract any
deviation from an equilibrium,
40
and promotes stability.
20
0
1900 1905 1910 1915 1920
Year
Snowshoe Hare Lynx

45. Topic 1: Systems
1.1.5: Feedback
80
Negative feedback
Number of pelts (1000s)
• tends to damp down, 60
neutralize or counteract any
deviation from an equilibrium,
40
and promotes stability.
Prey population
20
Prey population falls
grows
More food Less food 0
1900 1905 1910 1915 1920
Less hunting More hunting
Year
Snowshoe Hare Lynx
Predator population Predator population
falls grows

46. Topic 1: Systems
1.1.5: Feedback
Positive feedback

47. Topic 1: Systems
1.1.5: Feedback
Positive feedback
• Amplifies or increases
change; it leads to
exponential deviation away
from an equilibrium.

48. Topic 1: Systems
1.1.5: Feedback Higher temperatures
Positive feedback
• Amplifies or increases
change; it leads to
exponential deviation away
from an equilibrium.

49. Topic 1: Systems
1.1.5: Feedback Higher temperatures
Positive feedback Land and sea
• Amplifies or increases temperatures
rise
change; it leads to
exponential deviation away
from an equilibrium.

50. Topic 1: Systems
1.1.5: Feedback Higher temperatures
Positive feedback Land and sea
• Amplifies or increases temperatures
rise
change; it leads to
exponential deviation away
from an equilibrium. Increased evaporation

51. Topic 1: Systems
1.1.5: Feedback Higher temperatures
Positive feedback Land and sea
• Amplifies or increases temperatures
rise
change; it leads to
exponential deviation away
from an equilibrium. Increased evaporation
More water vapour

52. Topic 1: Systems
1.1.5: Feedback Higher temperatures
Positive feedback Land and sea
• Amplifies or increases temperatures
rise
change; it leads to
exponential deviation away
from an equilibrium. Wetter Atmosphere Increased evaporation
More water vapour

53. Topic 1: Systems
1.1.5: Feedback Higher temperatures
Positive feedback More heat trapped Land and sea
• Amplifies or increases by atmosphere temperatures
rise
change; it leads to
exponential deviation away
from an equilibrium. Wetter Atmosphere Increased evaporation
More water vapour

54. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems

55. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems
• A transfer is when the flow does not involve a change of
form

56. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems
• A transfer is when the flow does not involve a change of
form
• A transformation is a flow involving a change of form

57. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems
• A transfer is when the flow does not involve a change of
form
• A transformation is a flow involving a change of form
• Both types of flow use energy - transfers being simpler use
less

58. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems

59. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems

60. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems

61. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems

62. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems
Transfers can involve:

63. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems
Transfers can involve:
• The movement of material through living organisms (carnivores eating other animals)

64. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems
Transfers can involve:
• The movement of material through living organisms (carnivores eating other animals)
• The movement of material in a non-living process (water being carried by a stream)

65. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems
Transfers can involve:
• The movement of material through living organisms (carnivores eating other animals)
• The movement of material in a non-living process (water being carried by a stream)
• The movement of energy (ocean currents transferring heat)

66. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems

67. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems
Transformations can involve:

68. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems
Transformations can involve:
• Matter (glucose converted to starch in plants)

69. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems
Transformations can involve:
• Matter (glucose converted to starch in plants)
• Energy (Light converted to heat by radiating surfaces)

70. Topic 1: Systems
1.1.6: Transfers and Transformations
Both Material and Energy move or flow through ecosystems
Transformations can involve:
• Matter (glucose converted to starch in plants)
• Energy (Light converted to heat by radiating surfaces)
• Matter to energy (burning fossil fuels)

71. Topic 1: Systems
1.1.7: Flows and Storages
Both energy and matter flows (inputs and outputs) through
ecosystems but at times is also stored (stock) within the ecosystem: