Water, carbon, climate and life on Earth

Question 1

What is the relationship between the water and carbon cycle?

Answer 1

The ability of water to absorb and transfer carbon dioxide.

1. Pure water has a pH of 7 (neutral), however natural unpolluted rainwater is mildly acidic
2. This acidity comes from the natural presence of three substances: CO2, nitric acid and sulphur dioxide - CO2 is the greatest concentration
3. The combustion of fossil fuels releases gasses reacting with water particles in the atmosphere, leading to acidic rain
4. This enters as runoff and sinks into the ground harming the biosphere

Question 2

What is an example of a water and carbon cycle negative feedback loop?

Answer 2

• Phytoplankton live in the water using energy from the Sun with CO2 dissolved in water to photosynthesize
• Marine phytoplankton release a chemical substance, DMS, that may promote the formation of clouds over the oceans
• Increase in phytoplankton populations increase temperatures, and more sunshine increases global cooling and cloudiness because clouds reduce the amount of solar radiation reaching the surface of the Earth

(negative feedback)

Question 3

What is an example of a water and carbon cycle positive feedback loop?

Answer 3

1. Warmer temperatures
2. Increased decomposition
3. Increased tree root growth
4. Increased weathering
5. Carbon sequestration
6. Lower temperatures

Question 4

What was the Kyoto Protocol? (mitigating impacts of climate change case study)

Answer 4

• Agreement signed in 1997
• Put the emphasis on 38 HICs to reduce their emissions
• Some countries that weren’t required to sign the protocol are significant GHG emitters, such as Brazil, China and India

Question 5

How is the water cycle active within the Amazon rainforest? (relationship between the water and carbon cycle case study)

Answer 5

• Up to half of the rainfall in some areas may never reach the ground, being intercepted by forest and re-evaporated into the atmosphere
• 50-80% of moisture remains in the ecosystem’s water cycle
• Global effects =, as moisture created by rainforests travels around the world - influencing rain patterns in southeastern Europe and China

Question 6

What was done to protect mangroves in Sri Lanka? (mitigating climate change case study)

Answer 6

• Mangroves absorb more CO2 than other forests and fix it into the soil, where it is stored for hundreds of years
• In 2017, over 700,000 mangrove seedlings were propogated

Question 7

How was deforestation reduced in Brazil? (mitigation strategies for climate change case study)

Answer 7

• 2005, an ambitious plan to reduce rates of deforestation
• Landowners were required to preserve 80% of virgin forest, with punishments such as large fines or imprisonment
• By 2009, rates of deforestation fell by 75% compared with 2004

Question 8

What are the physical characteristics of the tropic rainforest?

Answer 8

• 2,000mm of rainfall per year and 27C temperatures
• Emit 28% of the world’s oxygen
• Home to 200million people

Question 9

How can deforestation impact the TRF water cycle?

Answer 9

• The atmosphere becomes less humid as evapotranspiration is reduced
• Less interception = rainfall reaches the ground immediately, compacting the soil and encouraging overland flow.

Question 10

How did deforestation impact Indonesia? (deforestation impacts case study)

Answer 10

• In 1960 80% was rainforest but rapid development has decimated large areas since then due to a demand for pulp, plywood and palm oil
• Under half of Indonesia’s original forest cover remains
• 30% of Indonesia’s forests are located on peatlands, once exposed, the peatlands are easily eroded and release CO2

Question 11

Where is the River Exe and its characteristics?

Answer 11

• 82.7km long, its source is in the hills of Exmoor and its mouth into the English Channel at Exmouth
• 84% comprises of impermeable Devonian sandstone = lots of runoff
• 67% is used as agricultural grassland

Question 12

What is the Wimbleball Reservoir?

Answer 12

• In 1979, the River Haddeo, an upland tributary was dammed to create the Reservoir
• 150 hectares surface area
• Regulates water flow, supplying Exeter and parts of East Devon

Question 13

What is the Exmoor Mires project?

Answer 13

• Aims to restore 2000hectaraes of Exmoor to the previous boggy conditions
• Indicated increased water storage in the peat of 260,000 cubic metres
• More carbon storage

Question 14

How is data being collected for the Exmoor Mires project, what were the results?

Answer 14

1. Scientists establish 3 experimental stations (pools) involving the installation of dipwell transects (surveys along a line), across newly blocked ditches
2. An electric contact dipmeter records the depth of the water table
3. This is inserted into the dipwell, and when the electrodes make contact with water, a buzzer is activated and a depth measurement can be taken

Results = More moisture is being retained within the soil