Lesson 11- How is climate change influencing the carbon cycle and can we mitigate it? Flashcards
1
Q
Types of greenhouse gas effect?
A
- The greenhouse gas effect
- The ENHANCED greenhouse gas effect
2
Q
Types of greenhouse gas effect-The greenhouse gas effect
A
- Electromagnetic radiation passes through the Earth’s atmosphere.
- The Earth absorbs most of the radiation and warms up.
- The Earth radiates energy as infrared radiation.
- Some of the infrared radiation goes into space.
- Some of the infrared radiation is absorbed by greenhouse gases in the atmosphere.
- The lower atmosphere warms up.
3
Q
Types of greenhouse gas effect-The ENHANCED greenhouse gas effect
A
- The Enhanced Greenhouse Effect is causing global warming as high levels of greenhouse gasesfrom humans, trapping radiation from the sun, causing global warming.
- The key point with this is that more incoming solar radiation is absorbed than let out into space this is known as radiative forcing
- 65% of radiative forcing is caused by CO2
4
Q
How does the enhanced greenhouse effect create positive feedback?
A
1)Humans increase CO2 in atmosphere by burning fossil fuels
2)This causes increased temperatures as the greenhouse effect is enhanced
3)This causes higher evaporation as temperatures are higher more of the year
4)This means there is more water vapor in the atmosphere acting as a greenhouse gas (50% of the greenhouse effect is water vapour) causing further warming
5
Q
How significant is the impact of water vapour on global warming?
A
- Although Co2 contributes less to the overall greenhouse effect than water vapour, scientists have found that it is the Co2 that controls the temperature.
- This rise in temperature is not all the warming that we will see based on current Co2 concentrations. There is a lag time between increased Co2 and increased warming.
- The temperature will increase by a further 0.6ºC because of the Co2 already in the atmosphere.
6
Q
What are all the causes of the enhanced greenhouse gas effect?
A
- Land Use Changes
- Fertilisers
- Deforestation
- Urbanisation
7
Q
Causes of enhanced greenhouse effect-Land Use Changes
A
- 10% of carbon released into the atmosphere by humans comes from agriculture impacting the soil and the biosphere.
For example - Farming Practices:
- In the Amazon, 70% of deforestation is for cattle ranching.
- Cattle produce methane, further contributing to global warming.
- Methane is more powerful than CO2 as a greenhouse gas so increases the enhanced greenhouse effect more rapidly.
8
Q
Causes of enhanced greenhouse gas effect- Fertilisers
A
- 5% of global human CO2 emissions
- Farming using fertiliser causes microbes in the soil to break down the nutrients in the crops, transferring carbon from the biosphere to the atmosphere, because it produces nitrous oxide which has a warming effect 265 times greater than CO2.
- Intensive farming uses lots of fertilisers, this causes the soil to get more acidic, this means that the amount of living/organic stuff in the soil is reduced. It is the living stuff that has the carbon in it so it decreases the amount of carbon stored in the soil.
9
Q
Causes of enhanced greenhouse gas effect- Deforestation
A
- In total, deforestation is 20% of all global greenhouse emissions.
- This is due to carbon being lost from the biosphere and transferred into the atmosphere as trees are cut down.
- The main impact of deforestation is when the land is used for other purposes such as farming, which then reduces carbon sequestration and land becomes a carbon source rather than a carbon sink.
10
Q
Causes of enhanced greenhouse gas effect- Urbanisation
A
- Replacing countryside with buildings and other similar infrastructure.
- Affects carbon byreplacing vegetation and covering soils.
- Urban areas are 2% of the world’s land mass, but account for 97% of all human caused global CO₂ emissions.
- Cement is an important building material, but releases carbon dioxide during production, contributing 7% to global carbon dioxide emissions each year, so sustainable options for recycling concrete are being developed.
11
Q
How can we mitigate the impacts of climate change?
A
- Global- International agreements
-National intervention-Climate change Act 2008 UK
-Regional intervention-EU 20-20-20 targets
-Local scale intervention- Providing home insulation
12
Q
How can we mitigate the impacts of climate change-Global Intervention
A
- Paris 2015 agreement meant 195 countries agreed to reduce global CO2 emissions to below 60% of 2010 levels by 2050
-Limit average global temp rise to 1.5 above pre-industrial levels
-HIC’s agreed to share technology and send funds to NEE’s and LIC’s to help them achieve their goals
13
Q
How can we mitigate the impacts of climate change- Weaknesses of global intervention
A
- Countries were allowed to set their own targets with no detailed timetable to follow
- LICs and NEEs argued that their current levels of development meant using cheaper fossil fuels to increase their people’s living standard to match HICs and why should they be made to reduce their emissions
- They argued that HICs had gained their current standards through industrialisation and the use of fossil fuels over the past 200 years, which made them responsible for the increase in current greenhouse gases
14
Q
How can we mitigate the impacts of climate change- Strengths of global intervention
A
- For the first time, countries agreed on the need to “transition away from fossil fuels in energy systems”.
- HICs expected to move away from coal, oil and gas more quickly
- Agreed to triple the capacity of renewable energy (wind and solar), and to double the rate of energy efficiency improvements by 2030.
- Increase the use of low- and zero-emission technologies like carbon capture and storage.
15
Q
How can we mitigate the impacts of climate change- Regional intervention
A
- 20% reduction in GHG emissions from 1990 levels and commitment to 20% of energy coming from renewable sources and 20% increase in energy efficiency by 2020.
16
Q
How can we mitigate the impacts of climate change- Has the regional intervention worked?
A
- EU achieved 20-20-20 climate targets, 55 % emissions cut by 2030 reachable with more efforts and policies
- EU greenhouse gas emissions decreased by 10 % from 2019 to 2020.
- The EU achieved a 21.3 % share of renewables in its energy consumption in 2020.
- The EU set a new 2030 target of a 55 % reduction in net greenhouse gas emissions
- However, only 21 Member States reached their national target in 2020 - Bulgaria, - Cyprus, Finland, Germany, Ireland and Malta did not meet the target.
17
Q
How can we mitigate the impacts of climate change- National intervention
-Climate change act 2008
A
- Legally binding target for the UK to reduce GHG emissions by 80% of 1990 levels by 2050 with a target of 26% by 2020 which has recently increased to 34%.
18
Q
How can we mitigate the impacts of climate change- National intervention
-Current government targets
A
- Greenhouse gas emissions to net zero by 2050
- UK’s electricity to come from low carbon sources (renewables and nuclear) by 2035
- Increase offshore wind capacity X5 by 2030
- Increase solar power capacity X5 by 2035
- The government has committed to installing 600,000 electric heat pumps a year by 2028 to replace gas boilers.
19
Q
How can we mitigate the impacts of climate change- National intervention
-Will the gov meet their targets
A
- The government is granting 100 oil and gas production licences for the North Sea.
- Delayed the ban on the sale of new petrol and diesel cars from 2030 to 2035
20
Q
How can we mitigate the impacts of climate change- Local intervention
A
- Improving home insulation
-Heat pumps - Smart pumps
- Electric cars
21
Q
How can we mitigate the impacts of climate change- Local intervention
-Improving home insulation
A
- New £1 billion UK GOV 2022 ECO+ scheme will see 100,000s of homes across the country receive new home insulation, saving consumers around £310 a year
22
Q
How can we mitigate the impacts of climate change- Local intervention
-Heat pumps
A
- In 2022, around 70,000 heat pumps were installed in the UK, leaving the government’s 600,000 target “significantly off track“
- A fifth of homes would never by required to switch from a fossil fuel boiler
- Grants to £7,500 to help homeowners in England and Wales install a heat pump
23
Q
How can we mitigate the impacts of climate change- Local intervention
-Smart Meters
A
- Using energy more wisely and use of smart meters and using public transport or car sharing schemes and calculating personal carbon footprints.
24
Q
How can we mitigate the impacts of climate change- Local intervention
-Electric cars
A
- To aid electric car take-up, the government wants 300,000 publicly-accessible charging points for electric cars by 2030.
25
How can we mitigate the impacts of climate change - Cap and Trade agreements
- Carbon offsets are credits for schemes that promote carbon sequestration (i.e. afforestation) or reduce emissions (i.e. use of renewable energy)
26
How can we mitigate the impacts of climate change- Cap and Trade agreements
-The Kyoto Protocol
- If a country cut its emissions below its 'cap', then another country could buy these 'credits' to offset their emissions above their agreed levels to meet their emission target or cap
- It was the idea that polluters have to pay while clean countries are rewarded
- In reality, very few countries achieved their cap and carbon credit trading wasn't successful
- New Zealand joined the Protocol in the belief they would make money selling their spare credits
- In reality, New Zealand exceeded their emissions cap and had to pay a fine
27
How can we mitigate the impacts of climate change- Cap and trade agreements
Eu 'carbon credit system'
- The EU introduced a similar carbon credit system in 2005
- If individual and energy-intensive businesses, such as refining and cement industries, achieved emissions below their set level, which they could then sell
28
How can we mitigate impacts of climate change- Carbon capture and Storage
- Carbon capture and storage facilities aim to prevent CO2 produced from industrial processes from being released into the atmosphere to limit global warming.
- Carbon is transferred from the atmosphere into the biosphere or lithosphere in solid or liquid form.
29
How can we mitigate impacts of climate change- Carbon capture and storage
-Natural CCS
- Natural CCS: Humans can try to increase the CO2 taken up by the natural world. For example, one global initiative aims to conserve, restore and plant one trillion trees worldwide by 2030
- Another natural example is developing peat bogs which stop vegetation decaying. This stores carbon naturally on land.
- In 2017 Brazil pledged to transform 70,000 acres of deforested rainforest by planting 73 million trees
30
How can we mitigate the impacts of climate change- Carbon capture and storage
-Artificial CCS
- Artificial CCS: involves the capture of CO2 from coal fired power plants. The captured carbon is then transported and piped underground and stored in rock strata porous enough to hold CO2
- Using rock with an impermeable cap (a layer on top that is impermeable) means that when carbon is stored within a porous rock it cannot escape back to the surface
- The UK government says the North Sea is an ideal place to store captured carbon, with plenty of old empty oil and gas reservoirs
- Under oceans is a more popular option as it is out of the way of people and is put in a place that is not being used for anything else.
31
How can we mitigate the impacts of climate change- Carbon capture and storage
- On land
- Easier to access and cheaper to build as sites are more accessible, however lots of people don’t want it near them as they don’t trust it not to leak.
32
How can we mitigate the impacts of climate change- Carbon capture and storage
-Under oceans
- More expensive as it is more difficult to get to.
- However it is much more away from people and therefore people think it is safer and not in the way.
33
How can we mitigate the impacts of climate change- Carbon capture and storage
- How effective will carbon capture be?
- Scientists estimate that this could cut global carbon emissions by up to 19%.
- However at the moment (2024) it only takes in 45 million tonnes of carbon out of 40 billion tonnes emitted each year
- It is also very expensive
- The government is aiming to capture and store between 20 and 30 million tonnes of CO2 a year by 2030.
- In March 2023, the Chancellor pledged £20bn in investment in carbon capture over the next 20 years
34
How can we mitigate the impacts of climate change- Changing agricultural and land use
1) Avoiding overgrazing- by livestock
2) Adding manures- and organic material rather than artificial fertilisers
3) Stock and crop rotation- to allow grassland and soil to recover
4) Carbon farming - one type of crop is replaced by another that absorbs more CO2 from the atmosphere – EG legumes and grasses
5) Irrigation and water management -improves plant productivity and prevents soil leaching
6) Reduced ploughing of fields- avoids decline of soil quality and carbon release
7) Polyculture - growing annual crops in between trees helps protect soils from erosion and boost stores of carbon
35
How can we mitigate the impacts of climate change- Changing agriculture and land use
-Example case study of it
Example: River Don
- 46 acres of land above the A616 Stocksbridge Bypass is used for grazing sheep which currently compact the soil and overgraze the land
-The soil here is being aerated (air put into it) to reduce compaction and increase carbon content
- 5000-6000 new trees are being planted here
- The livestock is being moved to different areas to avoid overgrazing
36
How can we mitigate the impacts of climate change- Changing agriculture and land use
-Peatlands
- Peatlands are thick organic soils that are low in oxygen and high in water (this is what we looked at on Saddleworth Moor when we did wildfires!)
- Decomposition doesn’t happen as there is a lack of oxygen and it causes carbon to be stored in the peat
- UK peatlands take 7000 years to form and are often 2-4m deep
- The Government is investing over £50 million in peat restoration to restore approximately 35,000 hectares of peatland
- The organic matter found within peat is 50% carbon peatlands are a major soil carbon sink
- Restoration of peatlands will increase carbon storage and removal from the atmosphere
37
How can we mitigate the impacts of climate change- Modifying deforestation
Methods of changing deforestation:
1) Protect existing forests to preserve current soil carbon stores
2) Reforesting degraded lands along with increasing tree density will improve biomass density and carbon storage
3) Planting Trees in croplands (agroforestry) and orchards can store carbon above and below ground
4) If we need to deforest still, grow as a renewable source: CO2 emissions can be reduced certification by the Forestry Stewardship Council (FSC) shows that timber has grown sustainably
5) Carbon payments can be made by countries or businesses to offset carbon emissions
6) Debt for nature swap:
- In 2010 the USA converted US$13.5 million of debt from Brazil into a fund to support the protection of the rainforest
7) The International Tropical Timber Agreement (ITTA) promotes sustainable forest management and restricts the trade in rainforest hardwood timber (hardwood timber is a slow-developing wood and therefore, holds more carbon within the wood)
8) Selective Management System in Malaysia allows for small-scale selective logging and replanting of trees
38
How can we mitigate the impacts of climate change- Modifying Photosynthesis
1) Having higher atmospheric carbon = more photosynthesis (carbon fertilization and negative feedback)
2) Using agroforestry (combining agriculture and planting trees) is better at absorbing CO2 as compared to natural forests
3) Doing afforestation
- Part of the northern forest (50 million trees to be planted) is in the river Don catchment
- Yorkshire water are planting 1 million trees by 2030, lots of these near Stocksbridge
4) Restoring peatlands where carbon has been removed from the atmosphere by peatland plants through photosynthesis
- UK Government is investing £50 million into peat restoration
5) Creating genetically engineered crops that will more efficiently remove and store carbon dioxide from the atmosphere
