Carbon - 3.1-3.4

Question 1

3.1 overall

Answer 1

Increased human use for resources is putting strain and imbalance on biosphere, carbon and water cycles

Question 2

How has the biosphere changed? 1

Answer 2

• Mainly for commodity prod
• Also land conversion
• 30% of global forest cover cleared, 20% degraded, and rest fragmented
• Energy use has increased (54%), population has increased 36%

Question 3

How has the biosphere changed? 2

Answer 3

• Developed countries use 50% of world’s energy, with N America being highest per capita – 10x Sub-Saharan Africa
• UK / USA temperate forests have the highest amount of clearance – 90% destroyed by 19th century
• Boreal changed later: since 1950s – oil/tar sands in Russia and Canada
• Tropical – mainly Indonesia for palm oil production and logging.

Question 4

Water cycle impact on this changing biosphere

Answer 4

• Transpiration from vegetation to the air
• Vegetation slows surface runoff and through flow.
• Interception of rainfall, increasing evaporation rates.
• Root systems increase rates of percolation.

Question 5

Soil health impact on biosphere

Answer 5

• need decomposing veg and roots, to release methane into atmosphere, add nutrients into soil
- Other vegetation: Provide humus for soil formation, Protects against soil erosion
• Fixes (draws down) nitrogen from the atmosphere

Question 6

Carbon cycle impact:

Answer 6

• Photosynthesis – take in CO2, emit O2, by low lying plants, leaves & shallow roots
• veg acts as a carbon sink
- Forest fires release trapped carbon + Also remove litter which could’ve decomposed
• Lack of water makes decomposition harder
• Dry soils emit CO2 – whilst wet soils store 3x the amount of carbon than vegetation

Question 7

Management of this changing biosphere

Answer 7

• IPCC thinks low-emission food crops, reducing food water, changing diets will help reduce food consumption
• Don’t get rid of any more undisturbed waterlogged peat soils (25% global storage)
• Restore degraded soils + afforestation
• fallow periods – retains soil moisture + organic matter.
• BUT: dangers of monoculture – e.g. commercial trees store less carbon, use more water and disease prone, e.g. China Green Wall

Question 8

Why are some countries involved in afforestation, while others in deforestation

Answer 8

Idea of development level, as countries who have developed over the last 20 years will have had to go through the short term environmental loss, but countries like the UK experienced this same loss many decades before, so now can the economic growth from this original revolution sparks neoliberal thinking, which urges them to protect their environment with the money generated from economic growth. (Kuznets concept)

Question 9

West Africa forest management project

Answer 9

• IGO project, between 11 countries and 15km wide, requires political unity
• building a great green wall
• Senegal has planted 11 million trees
• dry wells are filling up again, new economy sector developing and school attendance increased
• £8 billion cost
• more protected soil because more roots fro, trees - less soil degradation from wind

Question 10

China great green wall project

Answer 10

• to stop the advancements of the Gobi desert, the desertification and the degradation of arid/ semi arid ecosystems
  Desertification caused by deforestation and unsustainable agricultural practices has led to expansion of gobi desert
• tree planting project, wall of veg lining edges of gobi desert.
• Planned to finish by 2050 and plant 100 billion trees through aerial seeding and incentivising land owners to plant seeds

Question 11

Pros of China project

Answer 11

• has evidenced some mitigated desertification
• huge carbon sink
• reduced dust storm intensity

Question 12

Cons of China project

Answer 12

• some studies have shown further degradation of soil
• reduction in groundwater availability due to trees
• no consideration if different tree types for different regions in China.

Question 13

3.2 overall

Answer 13

Fossil fuels acidify the ocean, ruining this carbon sink

Question 14

Polyps

Answer 14

• tiny, soft bodied - feed on phytoplankton
• Protected by limestone, skeleton
• Attached to rocks on the sea floor
• Divide into thousands of clones

Question 15

Key point. Regarding carbon and ocean

Answer 15

Photosynthesis draws down and uses CO2

Question 16

What is ocean acidification?

Answer 16

• Sea is a carbon sink: absorbing CO2 (sea has 50x storage than land)
- so it could absorb 30% of GHG
• This creates a weak carbonic acid –i.e. the ocean becomes less alkaline
• Fossil fuels make this more intense

Question 17

How does it cause bleaching?

Answer 17

• Carbonic acid reacts with carbon ions – leaving more bicarbonate ions
• so corals need more energy to build shells become thinner / fragile
• More acidic water dissolves protective carbon shells

Question 18

Can it be natural?

Answer 18

• In the deep oceans , there is less photosynthesis - CO2 builds up.
• CO2 is also produced near volcanic vents

Question 19

Can ocean acidification be made worse?

Answer 19

• Combined with warmer temperatures, destructive cyclones, and pollution
• BUT: phytoplankton growth is good for coral

Question 20

When will ocean acidification cross the threshold?

Answer 20

• when the stress is so high that resilience is lost
• E.g. SST being too high
• E.g. pH < 7.8

Question 21

Positive feedback:

Answer 21

• Ocean acidification
• Decreased in dimethyl sulphide (produced by phytoplankton)
• Less sulphur compounds in atmosphere
• Less cloud condensation nuclei
• Less cloud cover
• Less sunlight reflection

Question 22

3.3 overall

Answer 22

Ecosystems are stressed, leading to drought and forest loss but not always

Question 23

Thermohaline shut down

Answer 23

• hypothesised effect of CC on major ocean circulation
• higher co2 emissions from anthrop = higher temps = higher glacial melt = higher freshwater input - less saline conditions
• as THC depends on water density differences, and for the colder water to absorb more, become denser and sink, higher temp - reduce the density differences
  = thermohaline shutdown
• huge impact on marine life as no utrients, higher occurrence of anorexic events, and drastic temp fall could lead to ice age

Question 24

Impacts of deforestation

Answer 24

• Palm Oil – Indonesia
• Loss of habitats
• Leaching
• Soil erosion into rivers

Question 25

Impacts on atmosphere and hydrosphere processes

Answer 25

• Hydrological cycle changes: inputs and outputs, i.e. trends in precipitation and evaporation.
• Soil moisture levels change, as well as rates of runoff and stream flow.
• Increased uncertainty over the security of water supplies.
• Increased frequency of drought due to shifting climate belts

Question 26

Impacts on biosphere processes

Answer 26

• Ocean and terrestrial photosynthesis regulates the composition of the atmosphere.
• Stored carbon influences soil health and ecosystem productivity.
• Forest health will deteriorate because of water stress

Question 27

Implications for wellbeing of ecosystems

Answer 27

• The health of wetland ecosystems are also likely to deteriorate and could suffer irreversible damage.
• Communities reliant on wetland ecosystems are threatened by increased food insecurity.
• Communities particularly in LHD are reliant on forests for fuel, medicines etc will lose vital ecosystem services

Question 28

What changes attitude?

Answer 28

• Increased wealth of countries
• Rising knowledge of the importance of the environment in human well-being
• Political systems – when environmental laws are enforced.
• Locals participation in designing (and managing) management systems
• Power and influence of TNCs

Question 29

What does Kuznetsk curve show the timeline of

Answer 29

the relationship between an economies growth and its environmental degradation levels

Question 30

Kuznets curve aligns with modern sociological theory

Answer 30

which allude to the idea that as an economy develops, they tend to pay more attention to the human rights and environment of their country, and invest in it to fix it

Question 31

The argument can then be made that if countries will follow Kuznets __

Answer 31

why not let all countries follow the trend and reach the turning point, just like the western countries have done in the 20th century?

Question 32

Why are people motivated to protect forests?

Answer 32

1. Drought frequency increase - 1 per 10 years in 1911, to yearly mega drought in 2011
2. Visible dieback of forest - 30% damaged, 5% visibly
3. 10% drop in photosynthesis as less co2 absorbed
4. Wildfire co2 emission increase

Question 33

Why are people motivated to protect forests 2

Answer 33

6. Aerosols and wind blown soil cause poor air quality, leading to respiratory Illnesses
7. 180% increase of hospitalisation, particularly under 5s
8. loss of ancestral land for the ayoreo in Paraguay

Question 34

3.4 overall

Answer 34

The arctic is degraded, with alterations water flow creating unusual geomorphological landscapes

Question 35

Batakgiata Crater

Answer 35

• Growing wider 33ft/year
• Melting began in 1960s, helped by deforestation, sun warming soil, ice melts, trees sink, don’t shade
• Damages pipelines, cracks pavement, swallows houses
• Potential release of 50% of methane

Question 36

Changes at the artic

Answer 36

• Arctic ponds dry up
• Humidity increases
• Increased melting of ice/snow/permafrost, particularly in spring
• More runoff
• More local river-ice flood

Question 37

Changes in carbon cycle

Answer 37

• CH4 from wetlands / sea floors / permafrost
• CO2 from forest fires
• Removal of sink and fires become a source of CO2
• High latitudes have warmed more than twice as fast as the global average.
• Thawing and degradation of permafrost, and hydrologic shifts that include earlier snowmelt and higher river discharge

Question 38

Kuparuk River, Alaska

Answer 38

• Mean annual flow has increased by 35% since the 1970s
• Snowmelt floods now arrive earlier.
• Floodwater is warmer, and the heat is transferred into the permafrost (which thaws)
• Old carbon is released from the Arctic floodplains into the atmosphere
- base is melting, which destabilises the infrastructure for community

Question 39

Positive feedback loop from permafrost melting

Answer 39

Melt - more carbon - higher temp - more temp

Question 40

Green wall of China facts.

Answer 40

• Over-exploitation of land (deforestation for agriculture) led to increasing desertification in NW China.
• 3,600km2 of grassland overtaken by Gobi Desert every year!
• Three-North Shelterbelt program: human-planted wind breaking forests –“afforestation”
• Begun in 1978
• Designed to hold back expansion of Gobi Desert
• 4,500 km long and due for completion in 2050

Question 41

Ocean acidification and coral reefs

Answer 41

Slows the rate at which coral reefs generate calcium carbonate, thus showing the growth of coral skeletons, thus making them more vulnerable to any damage

Also coral reefs are threatened by the rise in surface water temperatures, as seen with the widespread bleaching of the Great Barrier Reef

Question 42

Ph and ocean acidification

Answer 42

• Ocean acidification involves a decrease in the ph of oceans, caused by the uptake of carbon dioxide from the atmosphere, released by burning fossil fuels.
• Average ocean ph has fallen from 8.2 in early 1800s, to 8.1 in 2015, coral reefs stop growing when pH is less than 7.8 - a big risk

Question 43

Growing resource demands

Answer 43

• Deforestation levels: +500k hectares in china from 90-15, 250-500k in India, but Brazil + Indonesia had -500k hectares
• Grassland conversion: Temperate and tropical grasslands have also become heavily exploited by agriculture, both grassland types have suffered due to overexploitation.
• Urbanisation: removing space to urbanise means many ecosystems completely destroyed by the insatiable demand for space, not only are carbon sinks lost, but urban tends to mean an area of concentrated GHG emission as well as intense water demand

Question 44

Impacts of forest loss:

Answer 44

• Sequestering co2 from atmosphere
• Storing carbon
• Transferring moisture from the soil back into atmosphere by evapotranspiration

Question 45

Link this cc to kuznet

Answer 45

Theory seems to correct in suggesting that as countries reach higher levels of development and wealth, societies approach a tipping point when the costs of resource exploitation become fully realised.

Question 46

China and kuznet

Answer 46

China in 20th century = increase in income + environmental degradation, rising income worsened these impacts, china beginning to slow down rate of environmental degradation, and are gradually bringing in climate related schemes

Question 47

In reality fix to CC

Answer 47

In reality, saving climate depends on the fact that different players have different attitudes towards sustainability and environmental issues. Attitudes are largely determined by motives, so it could be argued that if these are economic, then their attitudes towards the environment may not be sympathetic

Question 48

UK kuznet

Answer 48

Uk went from 80% forest centuries ago, to <10% at the end of 1800s, to now 13% as uk developed and implemented forestry commission

Question 49

The arctic:
Plays an important role, as its sea ice regulates evaporation and precipitation.

Answer 49

• Temps here have risen twice as fast as global average
• There has been a considerable loss of sea ice, e.g. north west passage is now open to summer navigation
• Much melting of permafrost
• Carbon uptake by terrestrial plants is increasing due to a lengthening growing session
• Loss of albedo as ice that once covered land surface gives way to tundra, which gives way to taiga. Sunlight that was previously reflected back into space by white surface is now being increasingly absorbed by the ever darkening land surface, encouraging climate warming.