W&C cycles revision pack

Question 1

Outline how changes to the carbon cycle can affect the oceans. (4 marks)

Answer 1

• As humans release more Co2, 30-40% is absorbed by oceans
• The reaction between water and Co2 creates carbonic acid which breaks down marine calcification processes
• This causes coral bleaching, weaker plankton
• Deforestation reduces the carbon stored in the biosphere and results in global warming which melts ice sheets
• This results in a decrease salinity of oceans

Question 2

Outline the impact of long-term global temperature changes to the water cycle. (4 marks)

Answer 2

• Long-term global temperature increase is causing the water cycle to increase evaporation
• More evaporation leads to more precipitation
• Long-term global temperatures increase causes water stores to change
• Melting of ice and less snowfall
• This increases the amount of water in rivers