Water, Carbon and Climate + The Amazon Case Study

Describe water vapour feedback

- Increase in CO2 increases atmosphere temp

- Warm air holds more water vapour

- Water vapour holds more heat energy from sun

- Warmer climate

Is the water vapour feedback positive or negative?

Positive

Describe albedo feedback

- Bright ice surface - reflects sunlight

- Rising sea temps melt ice

- Less sunlight/radiation reflected

- More warming of sea

is the albedo feedback loop positive or negative

positive

Describe the permafrost feedback loop

- Rising temps thaw permafrost, releasing CO2 and methane

- Causes warming on local and global scale

- Higher temps cause more permafrost to melt

Is the permafrost feedback loop positive or negative

Positive

Describe the decreasing vegetation cover feedback loop

- Higher temps and more CO2

- More carbon fertilisation in plants - so they absorb more CO2

- Reduces levels of CO2 and rates of warming - reduces carbon fertilisation

Is the decreasing vegetation cover feedback loop positive or negative?

negative

Describe the increased vegetation due to higher CO2 feedback loop

- More CO2 means increased photosynthesis and rising global temps

- Allows vegetation to grow in new areas e.g. where permafrost has melted

- New vegetation absorbs CO2 from the atmosphere, decreasing the warming effect

Is the increased vegetation due to higher CO2 feedback loop positive or negative?

negative

Describe feedback of methane hydrates

If temps rise, potential of methane hydrates locked in the deep ocean to become destabilised and release.

How can climate change affect the water cycle?

Can cause parts of the water cycle to speed up as warming global temps increase the rate of evaporation worldwide - more evaporation causes more precipitation on average

How much higher are sea levels now than a century ago due to climate change?

0.1-0.2m

How much are sea levels expected to rise across the 21st century (if greenhouse gas emissions continue at projected levels)?

as much as 1.1 meters

What is mitigation?

Action intended to reduce the release of greenhouse gases into the atmospheric store.

Give an example of mitigation

Afforestation

Give an example of adaptation

Building coastal defences

What does adaptation involve?

Society adjusting to a warming climate

What is climate smart agriculture?

an approach to address the interlinked challenges related to food security and climate change

How is water harvesting used in climate smart agriculture?

Water harvesting captures runoff for better crops, helping farmers adapt to erratic rainfall in dry areas.

How are on farm trees used in climate smart agriculture?

Protect crops from wind, provide nutrients through their roots and leaves, are a source of fodder for livestock and firewood for the kitchen.

How are terraces used in climate smart agriculture?

On sloping land terraces are used to hold soil water and nutrients in place, helping to stabilise production

Give an example of a city adapting to rising sea levels

Venice - MOSE Barrier project

- 78 gates that can rise to block tide when needed and minimise risk of flooding

What is the main concern of the MOSE barrier project?

Concern it could destroy saltmarsh ecosystem that relies on flood waters in the Venetian lagoon

Describe China's sponge cities

Integrating wetlands, vegetation and open areas into urban areas to absorb and dissipate water

Give disadvantages of sponge cities

- Only able to absorb water to a certain point

- National standards and codes difficult to enforce

- Expensive and require a lot of space

When did sponge city design fail?

2021 - historic rainfall drained Zhengzhou, causing sponge city designs to fail

- more than 300 died from flooding

Describe carbon capture and sequestration (CCS) technologies

Involve capturing, transporting and storing CO2

How many CCS projects are there currently worldwide?

22 - 13 operational, 9 under construction

- Once all operational, will be able to capture 40 million tonnes of CO2

What is a disadvantage of CCS projects?

Will only be able to reduce global emissions by 0.1%

Describe UK afforestation project

Budget of £12 million to plant 500 hectares of trees across public land in England

Describe a fail of UK's afforestation project

In A14 (Cambridge) - half a million trees died before they could actually capture carbon

How has coal usage reduced in UK from 1990 to 2023?

reduced from 31.3% to 2.7%

What % of electricity is generated geothermally in Iceland?

30%

What % of homes in Iceland are supplied with renewable energy?

100%

What % of energy is supplied from hydroelectricity or geothermal energy in Iceland?

82%

What is the type of rainfall in the Amazon?

Convectional

What is the annual precipitation in the amazon?

2300mm

What is the temperature range in the Amazon?

26-30C

How much carbon is stored in the Amazon biomass?

100Gt

How much carbon is taken up by photosynthesis in the Amazon?

2.4Gt/year

How much carbon is released by decomposition and respiration in the Amazon?

1.7Gt

What the net primary productivity (rate of photosynthesis) of the amazon?

2500g/m2/yr

How much of the earth's terrestrial biomass does the earth account for?

17%

What proportion of carbon in the amazon is stored in soils?

40%

What proportion of carbon in the amazon is stored above the ground in leaves and branches?

60%

What was the rate of deforestation in the Amazon in 2022?

11,568km2

What proportion of deforestation is due to cattle ranching?

80%

What was the increase in surface runoff due to deforestation in the amazon?

27x more

What was the increase in surface temperature due to loss of forest cover?

+5C

Which river was dammed by the Belo Monte hydroelectric dam?

Xingu

What was the area flooded by the Belo Monte hydroelectric dam?

47km2

What was the reduction in water flow on the big bend of the river from the creation of the dam?

85%

What were the number of seed varieties used in muvaca seed dispersal strategy?

293

How many springs were rejuvenated by Instutio Terro afforestation in Minas Gerais?

8