The Role Of Feedback Within Cycles And Their Link To Climate Change And Inplications For Life On Earth

Question 1

Negative feedback in carbon cycle

Answer 1

CO2 in atmosphere increases- extra CO2 causes plants in land and ocean to inc growth - plants remove and store more CO2 in atmosphere - amount of CO2 in atmosphere is reduced

Question 2

Dynamic equilibrium in carbon cycle

Answer 2

Ocean acidification results from diffusion into oceans

Carbonate ions used by marine organisms to make shells are reduced

This is because carbonic acid reacts with carbonate ions to make bicarbonate

BUT

More acidic oceans lead to weathering of sedimentary rocks like limestone and chill

Release carbon ions in oceans

Balance stored

Question 3

Positive feedback in carbon cycle

Answer 3

Atmosphere temp inc EGE

Icebergs and sheets melt

Reflective light surfaces replaced by darker oceans which absorb heat

Ocean temp increase further

Question 4

Negative feedback in carbon and water cycle

Answer 4

More CO2 in atmosphere inc temp

Freshwater stored as ice is released in polar oceans

Salinity levels in ocean falls which disrupts ocean circulation

Gulf Stream is slowed and temps fall but not Galbally (NW Europe cooler)
Disrupts agriculture and trade
(For life on Earth and climate)

Question 5

Positive feedback in carbon and water cycle

Answer 5

Ocean heating up due to inc CO2 levels

EGE warms atmosphere and melts sea ice glaciers

Warmer oceans not able to absorbs as much CO2

So carbon stores in ocean are reduced and more in atmosphere

EGE

Warmer atmosphere (for life on Earth and climate change, more ice melting, sea life rise, and flooding)
(For climate change - climate becomes more extreme and less predictable)

Question 6

Dynamic equilibrium in carbon and water cycle

Answer 6

Ocean acidification

Carbonate ions used my marine animals to make shells

More acidic oceans lead to more weathering of sedimentary rocks

Release carbonate ions in oceans

Balance restored