3.1.1.1: Water and carbon cycle as natural systems Flashcards
Define system
A set of interrelated components working together towards a process
Define input
When matter or energy is added to a system
Define output
When matter or energy leaves a system
Define store/component
Where matter or energy builds up
Define flows/transfers
When matter or energy moves from one store to another
Define boundaries
Limits of a system
Define matter
Any physical substance involved in a system e.g. water/carbon
Define and give an example of an open system
Both energy and matter can enter and leave a system
e.g. Drainage basin: energy from sun enters and leaves system. Water is input as precipitation and output as river discharge
Define closed system and give an example
- Matter can’t enter or leave, it can only be recycled between stores. Energy can enter and leave a system as an input or output
e.g. Carbon cycle: energy is input by photosynthesis and output as respiration but amount of carbon matter on Earth stays the same
Define isolated system
Systems with no interactions with anything outside the system boundary. There is no input or output of energy or matter.Rare in nature
Define equillibrium within a system
When inputs and outputs are balanced so there are no overall changes to the system
Define dynamic equillibrium
Where the balance of inputs and outputs within a system change over time to establish a new balance
Define positive feedback
When a mechanism amplifies the effect of a change in inputs or outputs to move system further away from previous state
Define negative feedback
When a mechanism counteracts a change in inputs or outputs by keeping the system closer to its previous state
Give an example of positive feedback within the carbon cycle
- Temperature rises
- Ice cover melts
- Less ice cover means less of sun’s energy is reflected
- Less sun reflection means more sun absorption
- Increased CO2 release
- Temperature rises further
ALBEDO EFFECT
Give an example of negative feedback within the carbon cycle
- Large amounts of CO2 emitted
- CO2 conc increase in atmosphere
- Higher photosynthesis rates
- Increased plant growth
- Plants remove and store more CO2
- Amount of CO2 in atmosphere decreases
Give an example of negative feedback within the water cycle
- Increased temperature
- Increase in cloud formation as increased evaporation
- Cooling effect as increased cloud cover reflects incoming solar radiation so it isn’t absorbed by Earth’s surface
- Decreased temperature
Give an example of positive feedback within the water cycle
- Increased temperature
- More water vapour as increased rates of evaporation
- Water vapour is a greenhouse gas which traps heat in the atmosphere
- Temperature increase further
Give an input into the water cycle
Precipitation
Give an output of the water cycle
Surface run off
Give a form of energy within the water cycle
Latent heat associated with water changing state
Give examples of stores/components within the water cycle
Soil and trees
Give examples of flows/transfers within the water cycle
- Infiltration, groundwater flow and evaporation
Give an example of an input into the carbon cycle
Precipitation with dissolved CO2
