Booklet one - the water cycle

• Systems in geography

  Compromise any set of inter-related components that are connected to form a working unit
• elements of a system

  inputs

  Outputs

  Energy

  Stores / components

  Flows / transfers

  Positive feedback

  Negative feedback

  Dynamic equilibrium
• inputs

  material / energy moving into a system from outside
• outputs

  material / energy moving from the system to outside
• energy

  power / driving force
• stores / components

  individual elements / parts of a system
• flows / transfers

  links / relationships between components
• positive feedback

  cyclical sequence of events that amplifies / increases change

  • exacerbate outputs, driving it in one direction + promoting environmental instability
• Negative feedback

  cyclical sequence of events that damps down / neutralises effects of a system

  • Promotes environmental stability
• dynamic equilibrium

  state of balance within a constantly changing system
• whats an open system?

  Where matter and energy can enter and leave

  • Eg river drainage basin
• whats a closed system?

  transfer of energy in +out of the system, but no transfer of matter

  • eg the Earth, water cant/leave
• why do geographers use a systems approach?

  • way of simplifying a complex world and enables us to see the whole picture
  • Can apply it to physical systems (eg drainage basins) and human systems (eg farm operations)
  • Helps us understand how energy's transferred between components and how components change