Case Studies Flashcards
The Amazon Rainforest
Tropical rainforest:
- Covering 5.3 million sq km
- Sequesters 17% of all terrestrial carbon
- Some species, such as Brazil nut trees, dominate this process.
- 1% of the Amazon’s 16,000 tree species store 50% of its carbon, removing CO2 from the atmosphere for centuries.
Energy consumption: USA vs France
- top 10 energy consuming countries: USA 2nd, France 10th
- difference is explained by population; USA with 318.9mil, France with 64.6mil
- high USA consumption due to large inputs of energy required for heating/lighting in some areas, and air conditioning in others.
- USA: fossil fuels produce 82% of energy, 10% renewable energy, 8% nuclear energy (2014)
- France: fossil fuels produce 50% of energy, 9% renewable energy, 41% nuclear energy (2014)
- USA imported energy = 15%, France imported energy = 46%
- Overall the USA is more energy secure
Russian gas to Europe
- Russia is the world’s 2nd largest producer of gas
- Most of its gas exports go to Europe via a network of pipelines
- Geopolitically significant: 3/4 of the pipelines cross Ukraine, from which Russia recently annexed the Crimea in 2014.
- Ukraine has strength here, they could threaten to increase charges for Russian gas to pass through, or they could stop gas flows altogether
- Russia could either export most gas through the two northern pipelines in Finland and Poland, or they could annexe the Ukraine.
- Given the strained political relations between Russia and Western Europe, it would be strategically unwise for EU countries to become heavily reliant on Russian gas.
Canadian tar sands
- Exploiting the Canadian deposits on a commercial scale started in 1967 and has focused on the province of Alberta, most notably the Athabasca area.
- Tar sands produce about 40% of Canada’s oil output.
- The 2015 fall in the global price of oil had a depressing impact on the tar sands industry, as extracting bitumen is expensive due to the large energy output
US shale gas
- In 2000, shale gas provided 1% of the USA’s gas supply. In 2015 it was nearly 25%.
- Most of that increased production is due to the growing use of hydraulic fracturing (fracking) to release oil and gas from underground formations that are otherwise too difficult to drill.
- Most important shale gas fields are found in New York, Pennsylvania, Texas & West Virginia.
- Fracking is now a key determinant is US oil security and has an increasing influence on global oil price.
- Environmental concerns: possible contamination of groundwater by chemicals in the pumping fluid. Fracking is known to produce airborne pollutants such as methane, benzene and sulphur dioxide.
Brazilian deepwater oil
- Oil deposits far off the Brazilian coast discovered in 2006.
- By 2020, Petrobras (the state oil company) aims to raise production to 500,000 barrels of oil a day.
- There are concerns due to the serious pollution of coastal waters, and the risky nature of drilling so far offshore; the rigs are beyond the range of most helicopters and access by ship is made dangerous by the prevailing rough seas.
- Oil and gas reservoirs contain huge amounts of toxic, flammable gases. Observers wonder what will happen if there is an accident, such as occurred at the Deepwater Horizon rig in the Gulf of Mexico in 2010.
UK energy mix
- UK government is mindful of the need to become energy secure and to reduce global carbon emissions.
- 80% UK’s primary’s energy relies on oil (for transport) and natural gas (to generate electricity).
- This is unlikely to change much in the near future.
- However the UK is now more efficient both in producing energy and using it.
- Today we consume less energy than we did in 1970, despite a population increase of 6.5 million.
- Households now use 12% less energy while industry uses 60% less
- It now looks as if the UK will be using the same amount of energy in 2030 as it does today.
Biofuels in Brazil
- 1970s, Brazil took action to diversify its energy sources to combat its energy security
- It has since invested in alternative energy sources, hydroelectricity and recently, biofuels m.
- Today 4% of its energy comes from renewable sources.
- 90% new passenger vehicles sold in Brazil contain flex-fuel engines that work using any combination of petrol and sugar cane ethanol. This has led to significant reductions in the country’s CO2 emissions.
- Brazil is now the world’s largest producer of sugar cane, and also the leading exporter of sugar and ethanol.
- However due to large areas of central southern Brazil being set aside for the cultivation of sugar cane and production of ethanol, there has been displacement of other types of agriculture, particularly cattle rearing.
- The need to find replacement pastures has had a serious knock-on effect and resulted in large scale clearance of tropical rainforest in the Amazon Basin.
Amazon droughts
- Everyday the forest pumps 20 billion tonnes of water into the atmosphere.
- This is 3 billion tonnes more than the River Amazon discharges into the Atlantic Ocean.
- The forest’s uniform humidity lowers atmospheric pressure, allowing moisture from the Atlantic to reach almost across the continent.
- However, since 1990, a cycle of extreme drought and flooding has been observed. Droughts in 2005 and 2010 greatly degraded much of the forest already stressed by prolonged and large-scale deforestation.
- The diminishing health of the tropical rainforest means that it is declining as a carbon store, as well as sequestering less CO2 from the atmosphere, exacerbating the greenhouse effect.
Tropical forests (deforestation)
Tropical forests have lost half their area since the 1960s, especially in Africa and South America.
However, remote sensing shows that Indonesia has recently overtaken Brazil in the rate of deforestation, mainly for palm oil production and logging. Around 25% of the rainforest has been clear-felled or burnt in 25 years, with Borneo (Kalimantan) most affected.
UK forests (afforestation)
- Following centuries of exploitation, forest cover in the UK dropped from 80% to under 10% by the end of the 19th century.
- The Forestry Commission was set up in 1919 to remedy the country’s shortage of timber.
- It started to plant fast-growing exotic confers, such as Sitka Spruce, on the moors of Wales, the Scottish Highlands and the Lake District.
- By 2016, 13% of the UK’s land surface was forested, with increasing numbers of indigenous species planted.
Water conservation and management
ADAPTATION STRATEGY
+ Less resources used, less groundwater abstraction.
+ Attitudinal change operates on a long-term basis: use more grey water (recycled water)
- Efficiency and conservation cannot match increased demands for water.
- Changing cultural habits of a large water footprint needs promotion and enforcement by governments e.g smart meters
Resilient agricultural systems
ADAPTATION STRATEGY
+ Higher-tech, drought-tolerant species help resistance to climate change and increased diseases.
+ Low-tech measures and better practices generate healthier souls and may help CO2 sequestration and water storage: selective irrigation, mulching, cover crops, crop rotation, reduced ploughing, agroforestry.
+ More ‘indoor’ intensive farming.
- More expensive technology, seeds and breeds unavailable to poor subsistence farmers without aid.
- High energy costs from indoor and intensive farming.
- Genetic modification is still debated but increasingly used to create resistant strains e.g. rice and soya.
- Growing food insecurity in many places adds pressure to find ‘quick fixes’.
Land-use planning
ADAPTATION STRATEGY
+ Soft management: land-use zoning, building restrictions in vulnerable flood plains and low-lying coasts.
+ Enforcing strict runoff controls and soakaways.
- Public antipathy.
- Abandoning high-risk areas and land-use resettling is often unfeasible, as in megacities such as Dhaka, Bangladesh or Tokyo-Yokohama, Japan.
- A political ‘hot potato’.
- Needs strong governance, enforcement and compensation
Flood-risk management
ADAPTATION STRATEGY
+ Hard management traditionally used: localised flood defences, river dredging.
+ Simple changes can reduce flood risk, e.g. permeable tarmac.
+ Reduced deforestation and more afforestation upstream to absorb water and reduce downstream flood risk.
- Debate over funding sources, especially in times of economic austerity.
- Land owners may demand compensation for afforestation or ‘sacrificial land’ kept for flooding.
- Constant maintenance is needed in hard management e.g. dredging; lapses of management can increase risk.
- Ingrained culture of ‘techno-centric fixes’: a disbelief that technology cannot overcome natural processes.
