feedback mechanisms

• photosynthesis .

  A) increased

  B) rate

  C) CO2

  D) IR

  E) reduced

  
• cloud .

  A) increased

  B) evaporation

  C) albedo

  D) radiation

  E) reduced

  
• ice .

  A) ice

  B) reduction

  C) albedo

  D) decrease

  
• permafrost .

  A) melting

  B) bacteria

  C) anaerobically

  D) CO2

  
• methane .

  A) melt

  B) methane

  C) IR

  
• fire .

  A) droughts

  B) dry

  C) combustion

  D) IR

  
• cloud .

  A) increases

  B) water

  C) increased

  
• decomp .

  A) decomposition

  B) anaerobic

  C) CO2

  D) methane

  E) increased

  
• A positive feedback mechanism takes place when an environmental change causes other changes which increase the rate of the initial change. They do not return a system to equilibrium. 
• A negative feedback mechanism takes place when an environmental change, causes other changes which decrease the rate of the initial change.  They return a system back to equilibrium.