The carbon cycle and energy security (DONE) Flashcards
(317 cards)
1
Q
What forms can carbon exist as and how does it move between its forms?
A
- Carbon is a common element in the composition of the planet Earth.
- It exists in gas, liquid and solid forms, and in biotic (living) and abiotic (non-living) forms.
- carbon moves between these forms (the carbon pathway) through natural biogeochemical processes over a very long geological timescale.
2
Q
How does the balance of atmospheric gas change over time?
A
- The balance of atmospheric gases has changed over geological time because of changes in the Earth’s systems and processes.
3
Q
What happened to the balance of atmospheric gases during the Precambrian geological period?
A
- During the Precambrian geological period, volcanic activity added carbon dioxide (CO2), water (H2 0) and sulphur dioxide (S02) to the atmosphere at an exponential rate, forming the basic composition of the atmosphere today.
4
Q
What did primitive bacteria do to the atmosphere 3 billion years ago?
A
- When primitive bacteria such as cyanobacteria started photosynthesising 3 billion years ago, they added oxygen to the atmosphere and absorbed CO2 from it.
- The higher oxygen levels that resulted allowed more complex organisms to develop about 2 billion years ago
5
Q
How was CO2 in the early atmosphere stored?
A
- CO2 was dissolved in the
early oceans and then stored in sedimentary rocks. - This process accelerated when land-based (terrestrial) ecosystems developed about 400 million years ago (mya).
6
Q
When did the earth establish its present carbon cycle balance?
A
- The Earth established its present carbon cycle balance about 290 mya, at the time of the Carboniferous tropical rainforests.
7
Q
Why has the present carbon cycle been altered since the 1800s?
A
- The balance has been altered since about 1800 by human activities such as deforestation and the burning of fossil fuels, which release the stored carbon.
8
Q
How much carbon do crustal rocks contain in comparison with other elements?
A
- Overall, crustal rocks have a small amount of carbon (320 ppm) compared to other elements, especially oxygen (466,000 ppm) and silicon (277,000 ppm). I’m
9
Q
Which rocks have the highest concentrations of carbon?
A
- Sedimentary rocks, however, have much higher concentrations:
- limestone, for example, is about 42 per cent calcium carbonate by weight.
- while sandstone is 5 per cent
- shale (mudstone) is 3 per cent.
10
Q
What happened during the carboniferous period that reduced carbon concentrations in the atmosphere?
A
- During the Carboniferous period the formation of coal stored carbon underground and reduced concentrations in the atmosphere for 300 million years.
11
Q
What elements does the oceans mass consist of in %s?
A
- In oceans, carbon is only 0.003 per cent of the mass.
- while chlorine and sodium are 1.9 and 1.06 per cent respectively.
- with water making up 96.7 per cent.
12
Q
What types of carbon stores are there?
A
- There are small carbon stores, such as the organic part of marine ecosystems, and large carbon stores such as in the ocean.
13
Q
What are carbon stores also referred to as?
A
- The stores are sometimes referred to as ‘sinks’ or ‘reservoirs’.
14
Q
What are the exchanges of carbon between stores?
A
- There is an exchange of carbon between stores over a yearly timescale, called annual fluxes.
- but exchanges also take place over a longer timescale.
15
Q
What are the benefits of crude oil exploitation?
A
- Can be sold to bring wealth to a country and people - Can support industry, even in an economic recession • Easy to transport (e.g. pipeline or tanker)
- Large worldwide demand and thus a very tradable
commodity - Makes people’s lives easier, especially allowing fast air and land transport
- Has brought a culture based on freedom of movement
- Money from oil can be invested in nding the next flexible energy resource
16
Q
What are the problems of crude oil exploitation?
A
- Burning releases CO2, which contributes to global warming
- Burning releases NOx, which contributes to acid rain
- Wars have been fought over oil
- Cultures have become dependent on oil
- Fluctuations in the cost of the resource have caused recession and inflation.
- Oil spills may damage the natural environment (e.g. Exxon Valdez, Deepwater Horizon)
- Oil is a finite resource and will run out in the 21st century (estimated 2061)
17
Q
What is regarded as one of the main causes of anthropogenic greenhouse emissions and why?
A
- Population growth is regarded as one of the main causes of anthropogenic greenhouse emissions, because more people mean a higher demand for energy by households and businesses, and transport, deforestation and commercial farming all increase.
- The UN predicts that the world population will reach 9 billion by 2030 and 10 billion by 2050.
- Even though the growth rate is slowing, billions of people are being added, all of whom would like an improved quality of life which often leads to increased energy use.
18
Q
What are the 3 main objectives of energy players that The World Energy Council suggest?
A
- The World Energy Council has suggested that energy players have three objectives, but recognises that these may conflict and so will not be easy to achieve:
• Energy security: ensuring that energy supply meets current and future demand.
• Energy equity: ensuring accessible and a ordable energy for all countries.
• Environmental sustainability: ensuring efficient use of energy and use of renewable sources, so reducing pollution and moving towards lower greenhouse gas emissions.
19
Q
How has energy security been threatened during the ‘oil age’?
A
- During the ‘oil age’, energy security has been threatened by geopolitical tension, mainly in the Middle East since the 1973 Arab-Israeli war.
- More recent wars in Iraq, tensions between the USA and Iran, and the Arab uprising in North Africa and the Middle East have created political factions and terrorism.
- This attracted the involvement of the big energy players such as the USA and Russia, who wish to protect the energy pathways and supplies.
20
Q
Why do conflicts and tensions over energy security attract the involvement of the big energy players?
A
- TNCs that supply energy wish to keep trade flowing through the established pathways and to control prices.
- Governments gain the revenues from state-owned energy TNCs such as Gazprom (Russia), Petronas (Malaysia) and Saudi Aramco (Saudi Arabia), and in most countries governments impose high taxes on energy use, and use the revenues to help develop the country.
21
Q
Why is there conflict between environmental groups and large energy TNCs?
A
- There is a conflict with environmental groups concerned about damage to natural ecosystems and the slow progress that large energy TNCs are making towards ‘green energy’.
- While the number of major oil spills from tankers has decreased since double hulls were introduced in the 1990s, there are still risks of spills from pipelines in fragile environments and from extraction activities in deeper waters, including the Arctic Ocean.
- Governments are sometimes torn between ensuring a constant supply of energy and environmental considerations.
22
Q
Which countries in Europe have changed their energy mixes towards renewables?
A
- Many governments in Europe have been changing their energy mixes towards renewables, partly to meet ambitious CO2 reduction targets.
- The UK government has supported solar and wind energy, albeit inconsistently.
- Germany has invested greatly in renewables since a policy change in 1990
and then again since the Fukushima nuclear disaster of 2011.
23
Q
How has China’s energy mix influenced energy prices?
A
- When China decided
to develop its industries along more ‘western’ economic lines, China’s need for energy jumped
and the government sought resources in Africa. - This increased global energy prices, because they were competing to buy the available supplies.
- When China’s growth slowed significantly in 2015, energy prices fell, demonstrating their volatility.
24
Q
Who are a key group of energy players who can influence future energy mixes?
A
- A key group of energy players is the scientists and engineers, whose research and development into alternative energy resources and more efficient technologies can change future energy mixes and security.
25
How has production of oil, coal and natural gas varied from the mid 20th century?
- From the mid-20th century, countries with oil reserves beneffited from the wealth resulting from this valuable resource.
- During the last quarter of the 20th century and into the 21st century, production of oil, coal and natural gas steadily increased, with a dip in coal production in 2014.
- Emerging economies such as India and China have been responsible for increased global energy consumption since 2000, while in 2014 EU energy consumption fell to its lowest level since 1985.
26
How did oil consumption vary in 2014?
- Oil accounted for 32.6 per cent of global energy consumption, but was in slow decline (refining was at 80 per cent capacity), although production and refining remained high in the USA and the Middle East.
- The oil trade grew mainly because of China, which in 2013 had overtaken the USA as the world's largest importer of oil.
27
How did natural gas consumption vary in 2014?
- Natural gas accounted for 23.7 per cent of primary energy consumption, with the USA having the world's largest increase, but with declines in Russia, Netherlands and the EU as a whole.
- Trade fell in 2014, including pipeline shipments, which fell by 6. 2 per cent - the largest decline ever recorded.
28
How did coal consumption vary in 2014?
- Coal's share of global primary energy consumption declined to 30 per cent, mainly through slower Chinese economic growth.
- The Ukraine and the UK had significant decreases in consumption, while India posted the largest increase.
29
How are energy resources transported from source areas to areas of demand?
- Energy resources inevitably need to be transported from their source areas to areas of demand; this takes place by pipeline (oil and gas) over land, by bulk carrier ship (coal, uranium), tanker
ship (oil and LNG) by sea, or via underground electricity cables.
- All of these routes are called energy pathways.
30
What natural obstacles can cause energy pathways to become complex?
- Pathways between producers and consumers may be complex, because they must move through different natural and human environments.
- Natural obstacles include vast distances and difficult terrain such as the tundra in Alaska (Trans-Alaskan pipeline) and Siberia (Trans-Siberian pipeline).
- Extracting oil from the tar sands of Alberta in Canada or from deep water in the Gulf of Mexico - especially in hurricane season - also brings challenges.
31
How can technical problems cause energy pathways to become complex?
- Human obstacles, including technical problems such as pipeline leaks, could temporarily disrupt pathways.
- Supplies might run out, for example North Sea gas.
- Or supplies might be diverted for greater profit, such as to China.
32
What are choke points in energy pathways and how can they lead to pathways being blocked?
- Political tensions and disagreements may lead to pathways being blocked (at 'choke points').
- These choke points are subject to change, but many fossil fuel resources are in unstable locations such
as the Middle East and Russia, the South China Sea and the Red Sea.
- Examples include the Iraq wars (1990s), Somalian pirate activity, and Russian/Ukraine disputes (from 2004).
33
How can embargoes cause disruption in energy pathways?
- Embargoes and sanctions also disrupt production and supplies, such as from Iran and Russia.
- Pathway disruption can have socio-economic and political consequences, such as recession and job losses as well as energy shortages affecting lifestyles, and even armed conflicts to secure pathways and resource locations.
34
Why should energy pathways become less important in the future?
- These pathways should become less important as energy mixes change, because many renewable resources are ubiquitous.
35
Why will the search for other sources of energy intensify in the future?
- As fossil fuel reserves, notably oil, will soon be used up, especially as developed and emerging economies increase consumption, the search for other sources has intensified.
- This includes exploring deeper ocean areas such as the Gulf of Mexico, offshore Brazil and the Arctic Ocean, tar sands in Canada, and shale gas in the USA.
36
Where is deep water oil found?
- Deep-water oil is found in the Gulf of Mexico, where one of the largest and deepest oil elds is Atlantis (sea depth = 2,150 m).
37
How have the number of oil/gas platforms in the gulf of Mexico changed?
- Although the number of new oil/gas platforms in the Gulf of Mexico has decreased, they are getting larger and being located in deeper water.
- In 2010 only 14 rigs were in deep water, but by 2014 there were 63.
38
What was the USA's 2012-17 leasing plan for deep water oil?
- Drilling in deep water is not easy and there are hurricanes as well as long distances to shore for undersea pipelines.
- Despite this the USA's 2012-17 leasing plan extended the Gulf of Mexico area and also opened up the Alaskan Arctic, with the aim of reducing imports.
39
What does BP's Atlantis platform produce from deep-water oil?
- BP's Atlantis platform (2007-22) produces 200,000 barrels of oil and 5.1 million m3 of gas a day.
40
How has the deepwater horizon incident improved technology for deepwater oil extraction?
- Since the Deepwater Horizon incident (2010) highlighted the risks involved with deep-sea drilling, new regulations and technological improvements have been made.
- such as remotely operated underwater robots that can seal a leak within 45 seconds.
- However, environmental groups believe that cost cutting (due to recession and low oil prices), along with complacency and untested technologies, could lead to future large oil spills.
41
What are tar sands?
- Tar sands are a mixture of clay, sand, water and bitumen (very viscous oil).
42
How is oil from tar sands extracted?
- The oil is too thick to be pumped from the ground.
- Instead, it must be taken from an open pit, or strip-mined.
- To recover the oil it must be separated from the sands using very hot water diluted with lighter hydrocarbons.
43
Why may people start to extract oil from tar sands?
- When oil prices are high - at least US$120 a barrel - it becomes economical to extract oil from the sands.
44
What countries are the largest extractors of oil from tar sands?
- The largest reserves and production are in Alberta, Canada and in Venezuela (Orinoco Belt).
- Venezuela has more oil reserves than Saudi Arabia, which in 2012 raised its average GDP per capita (PPP) to US$12,772 and allowed the government to keep petrol prices very low
45
What are the issues with extraction of oil from tar sands?
- Issues with tar sands include the large amounts of energy needed (heating and pumping) even before the oil is used; this results in an estimated contribution to global warming three times higher than conventional oil.
- The mining process leaves scars on the landscape - which are refilled with the sands once the oil has been extracted.
- There are also impacts on local wildlife and people, leaks into water supplies from tailings ponds, and infringements of indigenous peoples' treaty rights over shing and hunting grounds.
46
How is oil shale formed?
- Oil shale contains solid bituminous material (kerogen) that formed when silt and organic matter were heated and pressurised under water, but not enough to turn it into oil.
47
How is oil shale extracted?
- Oil shale can be mined, but must be heated to a high temperature to release the oil; this is expensive and releases greenhouse gases.
48
Which countries have reserves of oil shale?
- The USA has large reserves in the Green River Formation of rocks in Colorado, Utah and Wyoming (perhaps 800 billion barrels).
- but currently there is little commercial development anywhere in the world.
- although in April 2016 it was reported that an Australian company would be expanding its oil shale exploration in Alaska.
49
What are the environmental impacts of the extraction of oil shale?
- Environmental impacts include:
- disturbance of land and vegetation cover.
- Disposal of the waste after processing (over 1 tonne of waste rock for every barrel of oil).
- Over-use of water resources (two barrels of water for every barrel of oil produced).
- Air and water pollution.
- However, the Royal Dutch Shell Company has developed a plan to heat shale underground while surrounded by a 'freeze wall', so that the kerogen seeps out into drilled holes for collection.
50
What is shale gas?
- Shale gas is natural gas (mostly methane) trapped inside impermeable shale rocks, so it cannot be extracted by normal drilling.
51
How is fracking used to extract shale gas?
- impermeable shale rocks cannot be drilled, instead the rock must be broken to free the gas, which is done
by hydraulic fracturing, more commonly called 'fracking'.
- This involves forcing water mixed with chemicals into the shale rock so that the rock splits apart and any gas flows into a prepared well where it is concentrated enough to recover.
52
What are the negative impacts of fracking for shale gas?
- Fracking can involve horizontal as well as vertical drilling, which reduces the impact on the ground surface, but many drill sites are needed because the gas is dispersed.
- Other negatives include:
- lowered local groundwater levels.
- possible chemical contamination of groundwater and surface water.
- methane gas leaks (not all the gas can be captured) adding to the greenhouse effect.
- risk of minor earth tremors and ground subsidence from altering the rock underground.
- Shale gas is still a fossil fuel, releasing carbon dioxide when combusted.
53
What are the positives of fracking for shale gas?
- Positives include:
- increasing the energy reserves of a country and reducing the need for imports.
- It is a flexible energy source; for example in 2015 in the USA natural gas overtook coal as the main generator of electricity.
- In addition, the carbon footprint of shale gas is about half that of coal and lower than liquefied natural gas (LNG), which is transported around the world.
54
What does the IPCC advise in order to drastically reduce climate change?
- In 2014 the IPCC concluded that, in order to drastically reduce enhanced climate change, the share of energy production that is accounted for by renewable energy sources needs to be trebled, and must dominate world energy supplies by 2050.
55
How much do renewables account for in global energy production?
- Renewables accounted for 3 per cent of global energy production in 2014, and continue to increase their share as action is taken to reduce dependence on fossil fuels and to mitigate climate change through reduced CO2 emissions.
56
How much do renewables account for in electricity production?
- Renewables represent 6 per cent of electricity production, especially in China, which accounted for all of the global increase in HEP production in 2014.
- Wind energy continues slowly to expand, but solar energy increased by 38.2 per cent in 2014.
57
How is the development of renewable and recyclable energy uncertain?
- The development of renewable and recyclable energy is uncertain:
- for example nuclear energy is an increasing source of energy in South Korea, China and France, but decreasing in Japan, Belgium, Germany and the UK.
- Hydroelectric energy is suffering from climate uncertainties; it had an increasing share of world energy production (6.8 per cent) in 2014, but drought conditions reduced outputs in Brazil and Turkey.
58
Where is there the greatest potential for solar energy?
- The greatest solar energy potential is in equatorial areas where sunlight and heat are most focused and intense.
- Also in desert areas where skies are clear, for example the Saharan and Great American deserts.
- Areas with potential include inland temperate regions that are not as affected by cloud cover, such as Germany.
- high-altitude areas where sunlight is more intense, such as the Tibetan plateau.
59
What can solar energy from the sun be used to do?
- Heat from the Sun can be used to heat water, or photoelectric cells can generate electricity directly.
60
Which country has invested most in solar energy?
- Germany has invested the most in solar energy, producing nearly 25,000 gigawatts of electricity.
- It can do this because it is a wealthy country able to invest in research and development and has a strong Green Party.
- It is aiming to cut CO2 emissions, and the 2011 Fukushima nuclear disaster in Japan (caused by a tsunami) encouraged them to develop alternatives.
61
What are the benefits of developing solar energy?
• Safe, clean and non-polluting once made
and installed.
• Renewable, so a sustainable source of energy.
• Can be used by poorer countries.
• Links well with other sources of energy.
• Flexible and modular, so can be used on
roofs of buildings or developed into a solar
power station.
62
What are the problems of developing solar energy?
• Not enough research and development, especially into storage methods.
• Electricity produced is initially more expensive than from conventional power
stations.
• Not very effective in cloudy climates or polar latitudes.
• Energy still needs to be stored for later use.
63
What did the IPCC identify as having a crucial role in mitigating climate change?
- In 2014 the IPCC identi ed bioenergy as having a crucial role in the mitigation of climate change through efficient biomass-to-bioenergy systems.
64
Why may bioenergy not be crucial in mitigating climate change?
- Biofuel is more suitable for small-scale rather than large scale operations and the resulting land use changes will have an impact on:
- carbon fluxes between soil, vegetation and atmosphere.
- food security where food crops are replaced by biomass crops.
- water resources (by changing the water cycle).
- conservation of the environment.
- the livelihoods of local people.
65
In which countries is the use of biofuels growing?
- The use of biofuels continues to grow slowly, mainly in the USA, Brazil, Indonesia and Argentina.
- In the UK, bioenergy accounted for 6.8 per cent of electricity production in 2014.
66
What are the challenges facing Africa when trying to increase the use of biofuels?
- Extensive areas in Africa are suitable for bio-ethanol (starch-based) or bio-diesel (oilseed) crops, but there are concerns about using land that is needed for food crops and water for people.
67
What are the negative impacts of the growing use of biofuels?
- Pressures from governments and companies could lead to changes in land ownership (tenure), reduce
the livelihoods of women, and take grasslands away from pastoralists or migrant farmers who need open access.
- Biofuel crops grown in marginal farming areas could also stress the natural environment and increase forest loss as people are forced to find new land.
- Deforestation would offset any carbon reduction benefits gained from switching to biofuels, so it would not be carbon-neutral.
68
Why is more research needed on biofuels?
- For example the Jatropha plant has been suggested as an oilseed crop for Africa, but oil yields are variable and unconfirmed, with little information on impacts.
- Also, in tropical South and Central America, palm oil is a significant biofuel crop, but is strongly linked to deforestation, especially in Colombia and Ecuador.
69
what are the negative impacts of using palm oil as a biofuels?
- In Peru, 72 per cent of new palm oil plantations were in forested areas, accounting for 1.3 per cent of the country's deforestation between 2000 and 2010.
70
How are biofuels able to impact Africa's carbon emissions?
- Biofuels can help Africa decrease carbon emissions:
- 24 per cent of non-electrical energy in 2012 was from biofuels and waste, compared with 16 per cent for the world as a whole.
- But biodiversity may be lost, food prices may increase and water resources may be stretched.
- Biofuels are climate-dependent, and future temperature and rainfall changes are not yet known with any certainty.
71
What could hydrogen fuel cells be used for?
- This alternative energy source could replace petrol for transport or natural gas for heating.
72
What does the term 'hydrogen economy' mean?
The term 'hydrogen economy' describes the possible widespread use of hydrogen as an energy source.
73
Why does hydrogen have an instant appeal as a fuel for radical technology?
- Hydrogen has an instant appeal because, whether it is combusted to produce heat or used in a fuel cell to produce electricity, the only waste product is water.
- One of its best potential uses is in electric cars or public vehicles that use fuel cells converting hydrogen as it can be obtained from a variety of sources.
- Fuel cells are also more efficient than a petrol or diesel engine.
74
What is an example of where a hydrogen fuel cell has been used commercially?
- Toyota developed a car
| with a fuel cell stack (the Mirai) and a range of 270 miles, which went on sale in California in 2015.
75
What are the disadvantages of using hydrogen as a fuel for radical technologies?
- Hydrogen is not found in a pure form and has to be separated from other compounds such as water, biomass, ethanol or natural gas (methane).
- Processes to separate it require large amounts of energy and may emit large quantities of greenhouse gases.
- Hydrogen is an energy carrier or a way of storing energy, rather than a primary energy source, and hydrogen tanks need to be strong enough to withstand impacts.
76
Why is further development needed for electric vehicles?
- The distances a purely electric vehicle can travel are relatively short before lengthy recharging
is needed, so further technological development is required.
- Range varies from 62 to 340 miles, depending on battery capacity and linked technologies.
77
How are charging points for electric vehicles distributed across urban and rural areas?
- Some communities, such as BedZED in the London borough of Sutton, have public charging points, but these are often scattered.
- According to Zap-Map (April 2016) there were 3,919 public charging locations in the U K to serve over 60,000 registered electric vehicles.
- London had 19.7 per cent of the charging points, and other cities have large concentrations.
- the fewest charging points are in rural regions of Wales (3 per cent) and the east of England (3.5 per cent).
- Therefore electric vehicles may be best suited to urban environments, helping cities reduce air pollution levels.
78
How do hybrid vehicles reduce carbon emissions?
- Hybrid vehicles, using a petrol or diesel engine in conjunction with an electric engine, have engine management systems that decide which is the most economical to use during a journey.
79
Which company uses radical technology and creates electric vehicles
- Tesla has manufactured electric vehicles since 2008.
- in 2016 it announced its third model and within three days had received 276,000 orders, with first deliveries planned for the end of 2017.
- However, it is not known if the small company can meet expectations.
80
What are the benefits of electric vehicles?
- The benefits of electric vehicles include zero carbon emissions and virtually no noise pollution, as well as being cheap to run.
81
What are the negatives of electric vehicles?
- They can be more expensive to buy than normal cars.
- They are so quiet that some people are concerned about collisions with pedestrians.
- Their biggest disadvantage is how the electricity is created for charging the batteries, because the carbon emissions of an electric vehicle depend on the energy profile of the country in which it is being used, so electric cars are more eco-friendly in Paraguay (hydroelectric) and Iceland (geothermal) than in India or Australia
(both coal).
82
What does a carbon capture and storage system do?
- A complete carbon capture and storage system (CCS) collects CO2 emissions from fixed points such as industrial and power plants, then transports the gas and injects it (in compressed form) into a suitable geological structure (over 800 m below ground).
- The storage is then monitored to ensure safety and no releases into the atmosphere.
83
Which country was the first to utilise CCS and what impact will it have on emissions?
- In 2014 Canada opened the first coal - fired power plant with CCS at Boundary Dam, at a cost of US$1.3 billion.
- It will reduce emissions by 90 per cent by pumping CO2 underground and selling it to an oil company (Cenovus) for 'priming' nearby oil fields; this helped make the scheme economical.
84
How can CCS be combined with bioenergy to remove co2 from the atmosphere?
- CCS can be combined with bioenergy (BECCS) to capture CO2 produced during bioenergy production such as ethanol.
- This ensures that there is a net removal of CO2 from the atmosphere, as all CO2 produced during farming is stored as well.
85
How did the IPCC rate CCS in mitigating climate change and how do they expect it to develop in the future?
- The 2014 IPCC report recognised the uncertain availability and deployment of this geo-engineering technology - in 2013 there were only 2 small BECCS operations.
- But the IPCC regarded it as an essential mitigation action to limit temperature increase to under 2°c by the end of the century.
- The IPCC believes that power generation without CCS must be phased out by 2100, and expects great progress after 2050.
86
What are the benefits of CCS?
- Lower pollution and climate benefits.
| - CCS could also extend the use of fossil fuels and encourage greater efficiency.
87
What are the negative impacts of CCS?
- Concerns include CO2 leakage affecting human health.
- Underground pressure causing small earthquakes.
- Increased water usage affecting natural environments.
88
What is nuclear fusion?
- Another radical technology is nuclear fusion, where two or more atomic nuclei join together
to make a new larger nucleus, releasing energy in the process.
89
What are the advantages of using nuclear fusion?
- The advantages of this energy source are that:
- it is clean, with no greenhouse gas emissions or radioactivity.
- and it requires common elements
90
How are countries working together to make nuclear fusion a reality?
- Nuclear fusion is still a long way from becoming a reality.
- But 35 countries are working together at the 500 MW International Thermonuclear Experimental Reactor (ITER) being constructed at Aix-en-Provence in France.
91
How did the Chinese take a step forward in research for nuclear fusion?
- In February 2016 a Chinese research team reported that it had managed to sustain a superheated plasma gas for over one-and-a-half minutes in a ring-shaped reactor using high-powered magnets.
- While this did not create usable energy, many regard it as a critical technical step forward.
92
How have the German government tried to encourage development of nuclear fusion?
- The German government has allocated over US$1.46 billion for research.
93
How can nanotechnologies make solar fuels?
- Another avanced approach uses nanotechnology to make solar fuels, which could replace fossil fuels.
- Solar fuels could be made using the action of sunlight on simple substances.
- This creates a photochemical reaction or artificial photosynthesis
- for example splitting water to make hydrogen.
- or using microorganisms or enzymes to 'harvest' light energy.
94
What did the annual report of the global footprint network show of the demand for resources?
- The 2015 annual report of the Global Footprint Network showed that it is beyond the capacity of the planet to satisfy current human demand for ecosystem services.
95
What did the global footprint networks ecological footprint show on carbon sequestration?
- Collecting accurate data on all variables is almost impossible, but the Network's Ecological Footprint showed that the average forest carbon sequestration per year is 0.73 tonnes of carbon per hectare.
96
What calculation is used to calculate impact of growing demand for resources?
I = P x A x C x T
- Where I is impact.
- P is population size.
- A is affluence of the population.
- C is consumer behaviour (C1 = food supply in calories and C2 = crop production volume)
- T is technology.
97
What does the equation for impacts of growing demand for resources show when applied to a situation?
- When applied to food production, it shows that population and affluence increase impacts as more food is grown.
- technology lowers impacts as it makes farming more efficient.
- Consumer behaviour may increase or decrease impacts through more or less consumption or through changing the ratio of food to non-food crops.
98
How has the population increase impacted the world energy use and is this the reason for increased demand?
- Between 1990 and 2015 world energy use increased by 54 per cent, while the population increased by 36 per cent.
- This shows that while population growth may increase energy use, it is economic development and prosperity that account for most of the increased demand.
99
Which countries use the most and least amount of energy?
- Developed countries use half of the world's energy.
- North America has the highest use per capita - more than ten times that of sub-Saharan Africa or South Asia.
- Many developing countries rely on wood or other biomass (such as charcoal or animal dung), which creates pressures on forests and impacts on human health.
100
How is the world population expected to grow by 2050?
- the world's population is expected to increase to 9.2 billion by 2050 (UN estimate), especially in South, East and South-East Asia.
- more food and resources will be required and more energy will be used.
101
Why is there a need to increase food production in some world regions?
- In 2015 an estimated 1.4 billion people su ered from hunger or malnutrition even though absolute poverty fell, so there is a need to increase food production in some world regions.
102
Why is there a need to cater for the tastes of a wealthier global population?
- There is also a need to cater for the tastes of a wealthier population:
- the Food and Agricultural Organisation (FAO) expects world meat consumption (37.4 kg/person in 2000) to increase to 52 kg/person per year by 2050.
103
How does the rising consumption of meat put strain on resources?
- Meat production is land and water intensive and requires more land for fodder crops, diverting farmland from staple crop production and degrading water and soil.
104
How has global food consumption increased over time and how will it increase in the future?
- World per capita food consumption (kcal/person/day) increased by 8.9 per cent between 1990 and 2015.
- But the FAO predicts that it will increase by only 3.5 per cent between 2015 and 2030.
105
How have increases in food consumption varied across the world?
- There are contrasting trends around the world with the largest increases in food consumption between 1990 and 2015 in East Asia (+20.1 per cent), sub-Saharan Africa (+14.1 per cent) and Latin America and the Caribbean (+11.9 per cent).
- But the FAO predicts a slowing of food consumption in all world regions except sub-Saharan Africa (+7.2 per cent) and South Asia (+7.0 per cent).
106
Which regions have had the greatest increase/decrease in CO2 emissions between 1996 - 2011?
- East Asia and pacific with 175.6% increase.
| - North America with 21.1% decrease.
107
Which regions have the greatest/lowest freshwater withdrawals as a % of internal water resources?
- The Middle East and North Africa with 133.6% in 2014.
| - Sub saharan Africa with 3.0% in 2014.
108
What % of greenhouse gas emissions did the IPCC estimate to be from agriculture?
- In 2013 the IPCC estimated that 24 per cent of greenhouse gas emissions came from agriculture and land-use change.
- such as biomass burning.
- deforestation
- methane emissions from livestock farming and wet rice cultivation.
109
How have global forest areas and arable areas varied between 1995 and 2005?
- Between 1995 and 2005 the global forest area decreased by 80 million ha, while arable land area increased by 24 million ha.
110
What does the UNEP expect to happen to natural grounds between 2005 and 2050?
- At current rates the United Nations Environment Programme (UNEP) expects that between 320 and 850 million ha of natural grasslands, savannah or forest could be lost to crops between 2005 and 2050.
- In order to prevent this it
needs to be stopped by 2020.
111
How is the amount of farmland changing across developed and emerging countries?
- Emissions are decreasing in developed countries as the amount of farmland decreases; farming area is stable in the poorest and emerging countries, but is increasing in developing countries.
112
What do the FAO think will happen as a result of changes to agriculture and increasing meat production?
- The FAO believe that changes to agriculture in sub-Saharan Africa could increase deforestation and carbon emissions, even with efficient changes.
- Increasing meat production could increase methane emissions in India and China.
113
What do the IPCC recommend to reduce greenhouse gas emissions?
- The IPCC recommends a switch to low-emission food crops.
- Changing croplands to forests or bioenergy crops.
- reducing food waste (30 to 40 per cent is lost from 'farm to fork').
- Changing diets (plants not meat) and reducing food consumption.
114
Why are degraded soils unable to store much carbon?
- Degraded soils, particularly organic soils that have lost organic matter and moisture, are not capable of storing much carbon.
- When soils dry out through lack of vegetation cover, drainage or evaporation from increased temperatures, they emit rather than store greenhouse gases.
115
How does soil as a carbon store compare to vegetation?
- It is estimated that soils can store three times more carbon than vegetation
116
What impacts the amount of carbon which soil can store?
- The amount of carbon in soil is decided by inputs of dead plant material and outputs from decomposition and mineralisation.
117
Why is land management important for the carbon in soil?
- Land management is important, especially in areas of moist, peat - rich soil:
- undisturbed waterlogged peat soils, which cover 3 per cent of the world's land area, store up to 25 per cent of the global soil carbon store.
- However, drainage has increased decomposition, respiration, fire risk and emissions of CO2 and N2O, especially in Asia and Europe.
118
How can degraded soils be restored?
- Degraded soils can be restored through managing fertility and water conservation.
- along with afforestation and longer fallow periods (conservation tillage).
- all of which help retain soil moisture and organic matter.
119
How is ocean acidification changing over time?
- Acidification of the oceans is increasing as the sea absorbs more CO2 from the atmosphere.
120
How has ocean acidity changed since the industrial revolution?
- Since the Industrial Revolution, pH has fallen by 0.1 (to 8.1), which on the log scale is a 26 per cent increase in acidity.
121
Why are oceans an important store of carbon?
- Oceans are able to store 50 times more inorganic carbon than the atmosphere.
- The carbon and the ocean create a weak H2CO3 acid by releasing hydrogen ions.
- The ocean is an important carbon sink for anthropogenic CO2 emissions.
122
How much of anthropogenic CO2 emissions do the oceans absorb but why does this vary?
- In 2014 the IPCC reported that the oceans had absorbed about 30 per cent of anthropogenic CO2 emissions.
- Absorption rates vary because of ocean oscillations, such as El Nino, and sea temperatures.
123
Where has the largest and smallest pH reduction in oceans been?
- The largest pH reduction has been in the North Atlantic.
| - The smallest in the subtropical waters of the southern Pacific.
124
Why can it be difficult to determine the effects of ocean acidification?
- It is not easy to separate the effects of acidification from those of sea-level rise and seawater temperature increase.
125
How much have sea levels risen since the 1900's?
- Sea levels have risen at an accelerating rate:
- by 1.7 mm/yr between 1901 and 2010.
- by 3.2 mm/yr between 1993 and 2010.
126
What are the main reasons for the sea level rises?
- This increase is due to thermal expansion.
- glacier mass loss.
- ice sheet loss
- increased water storage on land.
127
Why are there often regional differences in sea level rise?
- Regional differences in sea-level rise are due to ocean currents and planetary winds pushing water towards certain coasts, such as the western Pacific.
128
How much heat energy do oceans store and how is the distribution of heat changing?
- Oceans stored 90 per cent of heat energy between 1971 and 2010.
- The upper 75 m has been warming by 0.11°c per decade during this period.
- Deeper layers are now also warming.
129
How are salinity patterns changing in oceans?
- Salinity patterns are changing as salty areas are getting saltier and fresher areas are becoming less salty.
- one reason for this is the changing evaporation and precipitation patterns over oceans which impact salinity.
- changing evaporation and precipitation are also affecting the movements of ocean currents and the thermohaline circulation.
130
When may the physiology and behaviour patterns of marine organisms change?
- The physiology and behaviour patterns of marine organisms are expected to change, perhaps at a tipping point.
131
How will ocean acidification impact marine organisms?
- Marine plants, phytoplankton and microalgae may benefit from increased photosynthesis.
- crustaceans and some fish may be less sensitive.
- But higher acidity may affect the ability of marine organisms to build shells and skeletons, causing thinner or smaller shells in molluscs and therefore reducing coral reef building ability.
132
How may ocean acidification impact the minerals and fishes intake?
- Acidity may also reduce the availability of minerals, and there may be a build-up of CO2 concentrations in fish, squid and mussels.
133
How is ocean acidification changing causing the death of certain species in some oceans?
- Larval oyster fatalities have already been noted in the north-eastern Pacific.
- Fleshy algae and barnacles are replacing mussels.
134
How is ocean acidification creating a cascade effect from the impact on coral reefs?
- It is feared that the impact on cold and warm water corals will be negative.
- This reducing habitats for other marine life in the ecosystem.
- Leading to a decline in biodiversity and ecosystem productivity (the cascade effect).
135
What do climate change models suggest about shifting climates?
- Climate change models suggest that global weather patterns may be shifting, resulting in permanent changes that make some world regions wetter and others drier.
136
What do scientists consider a key element in offsetting carbon emissions?
- Some scientists
| regard the tropical rainforest in Amazonia as a key element in offsetting anthropogenic carbon emissions.
137
Why do scientists feel that tropical rainforests are now unable to offset carbon emissions?
- Scientists are worried that a climate tipping point may be reached.
- This is where the temperature and precipitation levels become unfavourable for tree growth.
- This will cause the biome to change to savannah grassland instead.
138
When may climates shift due to thermohaline circulation?
- Climates may shift if the thermohaline circulation changes.
- This could happen if a large input of freshwater occurs due to greater precipitation.
- Or melting glaciers and ice sheets (such as in Greenland) or melting sea ice (such as in the Arctic Ocean).
139
How would changes in thermohaline circulation impact salinity levels and what impacts would this have on the ocean?
- Salinity levels would be reduced.
- This would alter seawater density.
- for example in the North Atlantic; this would prevent the Gulf Stream current reaching as far north, and would reduce the warming influence of the sea on north western Europe.
140
Why is the climate change in NW Europe difficult to predict?
- Climate change in NW Europe is difficult to predict because atmospheric temperatures will be increasing due to global warming, possibly at a greater rate than any decrease from a cooler sea.
141
What did Landsat satellite data for 2000 - 2012 show about the worlds forests?
- Landsat satellite data for 2000 to 2012 showed the loss of 2.3 million km2 of the world's forests, and 0.8 million km2 gained.
142
Where have their been decreases in tropical forests shown by Landsat satellite data between 2000 - 2012?
- Tropical forests had a trend of losses every year, for example in Bolivia, Indonesia and Angola.
143
What are the main causes of changes in tropical and boreal forests?
- Intensive forestry in tropical climates caused the highest rates of change.
- While boreal forests had losses from both fire and forestry.
144
What processes do tropical rainforests have a major influence over?
- Tropical rainforests have a major influence on regional and global climates and the carbon cycle (carbon storage) as well as on the water cycle through interception, absorption and evapotranspiration, a ecting water supplies for people
145
What % of forest loss is from tropical rainforests?
- Tropical rainforests account for 32 percent of the global loss of forests, half of this is in South America.
146
What human activities contribute to forest loss?
- Forest loss from human activities has been a key concern since about 1970 and, while deforestation rates have slowed in some areas such as Brazil, it is still taking place.
147
Why is it hard to predict future forest loss?
- Predicting future forest loss (or gain) is problematic:
- Past surges of deforestation have made way for soya farms, palm oil plantations and hydroelectric power dams.
- Policy changes may have an effect: Brazil's policies show how a country can create a 'turning point', as shown in the Kuznets Curve.
148
Where does fire cause forest loss and what impact can it have on humans?
- Fire is one of the main causes of forest loss, especially along drier forest edges.
- As a drier forest decays and is destroyed by fire, emissions of solid particles (aerosols) and wind-blown soil result in impaired air quality.
- This causes human respiratory problems to increase.
149
How did the 2005 and 2010 Amazonia droughts cause problems for humans?
- During the 2005 Amazonia drought, Capixaba in Acre State, Brazil, experienced a 181 per cent increase in hospitalisations.
- and in 2010, Fatima in Tocantins State had a 267 per cent increase (especially of under-fives).
150
How can drier soils caused by droughts have negative impacts?
- Drier soils and the lack of protection from vegetation cover increase soil erosion, which again may affect food supplies in the longer term.
151
What is the environmental Kuznets curve based on and what does it suggest?
- The environmental Kuznets Curve is based on economic principles.
- It suggests that as a country develops, damage to the natural environment will at first increase as resources are exploited and technologies cause pollution and degradation.
- But over time, as technology becomes more efficient, fewer resources are used, new resources are created and pollution levels fall.
152
In which countries are forests being removed for fuel, to create farmland or to create living space?
- All countries have removed natural forests to create farmland or living space or for fuel.
- This is occurring now in emerging countries such as Indonesia.
- Indonesia has had the largest increase in forest loss from 2000 to 2012 with a loss of over 20,000 km2 per year in 2011/12.
- Other developing countries will also face this problem.
153
Why is afforestation now happening in developed countries?
In many developed countries, afforestation is now taking place, for a mixture of resource reasons and environmental reasons such as improving carbon balance and the hydrological cycle.
154
Why did Eurasian boreal forests have the greatest expansion from 2000 - 2012?
- Eurasian boreal forests had the greatest expansion from 2000 to 2012 as a result of forestry management, reduced farmland and recovery after wild fires.
155
Which country had the largest global forest loss between 2000 - 2012?
- Russia had the largest global forest loss between 2000 and 2012 - 365,015 km2
156
Why is more research needed to tell whether climate change has impacted precipitation patterns?
- Changes to precipitation patterns due to climate change are complex.
- More research is needed to separate natural variability from long-term change.
157
What is one way which climate change may limit precipitation?
- One possibility is that the warming of the oceans and the lower atmosphere will result in a smaller temperature gradient within
the troposphere.
- This would create stability, weaken planetary winds and limit increases in precipitation.
158
What is a way which climate change may increase precipitation?
- Higher temperatures will increase evaporation.
| - This will lead to increased precipitation at the lntertropical Convergence Zone (ITCZ) and at polar latitudes.
159
How have oceans supplied resources for people?
- Oceans have always supplied resources for people.
- Increasingly in recent decades food supplies for many developing countries with growing populations have been based on marine resources.
160
How is ocean health being affected?
- Ocean health is being affected by increasing temperature, acidity, salinity and possible changes to currents.
161
What impact do changes to coral reefs have on ecosystem services?
- Changes to coral reefs which are the most biodiverse marine ecosystem, have an impact on ecosystem services.
- Changes cause a loss of cultural and leisure opportunities and reduce the protection from storms that reefs offer coasts.
162
How may the ability of countries to harvest marine resources through fishing change?
- The ability of countries to harvest marine resources through fishing could change.
- especially if there is a poleward shift of fish species, suggested to be occurring at a rate of around 26 km per decade.
163
How may conflicts between players occur over the shift of fish species?
- Conflict between players may occur if Marine Protection Areas (MPA) end up in the wrong places.
- Territorial disputes over the new locations of fish stocks may also arise.
164
What are natural variations in climate caused by?
- Natural variations in climate are caused by:
- Milankovitch cycles.
- Sun cycles.
- long-term ocean and atmospheric oscillations such as El Nino and jet streams.
- All of these create uncertainty when trying to predict future climate change.
165
How can physical and human factors make it hard to predict future climate change?
- physical factors such as sun cycles, ocean and atmospheric oscillations create uncertainty for future climate change.
- Similarly, human factors such as population growth, economic growth, land-use change and energy profiles may change in the future and alter anthropogenic greenhouse gas emissions.
166
What would happen if carbon emissions were suddenly stopped?
- If emissions were stopped, some effects of greenhouse gases would immediately be reduced, but others could take centuries to be rebalanced by Earth's systems.
167
Why wouldn't a sudden stop of carbon emissions enable the carbon cycle to return to a balance easily?
- Even an immediate drastic reduction would not enable the carbon cycle to return to a balance easily.
- This is because oceans would be saturated and vegetation unable to absorb more.
168
IF CH4 and HCFCs emissions were reduced to zero how long would it take for the atmosphere to return to normal?
- If CH4 and HCFCs emissions were reduced to zero, the atmosphere would return to normal concentrations within 100 years.
- A 30% reduction would stabilise the warming effect.
169
If emissions were suddenly stopped how much carbon would stay in the atmosphere for how long?
- Around 20 per cent of CO2 could remain in the atmosphere for several hundred years.
170
What reduction of nitrous oxide would allow the atmosphere to return to normal?
- Nitrous oxide has a lifetime in the atmosphere of 110 years.
- It would require a 50 per cent reduction to stabilise.
- zero emissions would return a natural balance in about 200 years.
- Any continuing emissions will lengthen the time period of anthropogenic warming.
171
What do the IPCC define a tipping point as?
- In 2014 the IPCC defined a 'tipping point' as an abrupt, possibly irreversible, large scale change over a few decades or less.
- The IPCC identified seven possible tipping points.
172
What seven tipping points did the IPCC identify?
- Atlantic thermohaline circulation collapse.
- Seabed methane release.
- Dieback of tropical rainforests.
- Dieback of boreal forests.
- Arctic Ocean free of sea ice in summer.
- Long term droughts.
- Collapse of monsoon climate circulation.
173
How could an Atlantic thermohaline circulation collapse be a tipping point?
- increased volumes of freshwater and density changes may alter currents in the Atlantic (but climate models do not agree).
174
How could seabed methane release be a tipping point?
- Methane hydrates in seabed sediments (clathrates) could be destabilised by warming.
- releasing methane gas from a solid form (this is considered very unlikely).
175
How could dieback of tropical rainforests be a tipping point?
- Moist, complex forests, such as in Amazonia, could change to a less carbon-dense, drought - and fire -adapted ecosystem because of longer dry seasons (but a collapse over large areas is unpredictable).
176
How could the Arctic Ocean free of sea ice in summer be a tipping point?
- Higher air temperatures and a warmer ocean melt sea ice(considered likely).
- However, some research suggests that thinner ice and snow cover may increase albedo and cooling (but this negative feedback is not fully understood).
177
How could long term droughts be a tipping point?
- The subtropical dry zone moves poleward as large-scale atmospheric circulation modifies the Hadley cell over a long timescale (however the frequency and duration of mega-droughts in the world is not predictable).
178
How could collapse of monsoon climate circulation be a tipping point?
- More intense precipitation occurs during the monsoon wet season because of the transport of more evaporated moisture in warmer air (however a sudden collapse is not predictable).
179
What 2 the tipping points may occur other than the 7 decided by the IPCC?
Two other possibilities ma occu slowly: collapse of the Greenland or Antarctic ice sheets, and methane release from melting permafrost.
180
Why may species extinction be abrupt in flat and high altitude landscapes?
- Around the world, species extinction may be abrupt in flat and high altitude landscapes when a critical threshold is reached because flora and fauna have nowhere else to go.
181
What ecosystems are often unable to survive in oceans due to the temperature and sea level?
- In oceans, warm water coral reefs are unable to survive in cooler deeper water.
- Low-lying ecosystems flooded by sea-level rise could disappear completely.
- Any of these changes would have a cascade effect through food webs, affecting food sources.
182
What do Earth system models suggest about how much CO2 oceans will absorb?
- Earth system models (ESMs) suggest that oceans will absorb more CO2 from the atmosphere, but
a concern is what happens when the ocean reaches saturation point.
183
Why is there uncertainty about terrestrial ecosystem carbon uptake?
- There is uncertainty about terrestrial ecosystem carbon uptake because of vulnerability to human activities, fire and respiration changes, which would return carbon to the atmosphere (positive feedback).
184
What positive feedback occurs and releases greenhouse gases into the atmosphere?
- Other positive feedbacks include reduced reflection (albedo) of solar radiation by the Earth's surface.
- Snow and ice melt, and darker surfaces absorb more heat energy, and methane releases.
185
What are possible negative feedbacks around carbon emissions in the atmosphere and climate change?
- Increased plant growth as a result of higher CO2 concentrations.
- Reduced CO2 concentrations in the atmosphere slowing the rate of warming.
- An increase in cloud cover due to higher evaporation rates which would reflect solar energy.
- - Dust from drier climates entering the atmosphere and reducing the amount of incoming solar radiation.
186
What feedbacks are not yet known about carbon emissions and climate change?
- Most feedbacks are not yet known.
- For example links between soil moisture and precipitation or between atmospheric chemistry and the biosphere.
- But overall it is expected that feedback between climate change and the carbon cycle will amplify global warming.
187
What are geo-engineering adaptation strategies to manage solar radiation?
- Spray seawater into atmosphere: would provide hygroscopic nuclei for condensation to take place, creating bright white
clouds that reflect Sun's energy into space.
- Add sulphur particles to stratosphere: the aerosol particles formed would reflect the Sun's energy back into space.
- Trillions of wafer-thin discs in stationary orbit between the Earth and Sun: these would reduce the amount of the Sun's energy reaching the planet.
188
What are potential problems with the geo-engineering adaptation strategies to manage solar radiation?
- Seawater spray: May cause unpredictable weather changes, such as reduced precipitation and changes to regional temperatures. The albedo effect is not fully understood.
- Sulphur particles in stratosphere: May cause unpredictable weather changes such as reduced evaporation. May affect stability of ozone layer and increase acid rain over large areas.
- Discs in orbit between earth and sun: Very expensive, at least US$5 trillion. Unpredictable effect on whole atmosphere as heat budget would be changed. All countries would have to agree.
189
How will countries need to take action to adapt to climate change?
- Some populations may become environmental refugees and move away from uninhabitable areas if they are flooded because of sea-level rise or prone to increased mega-droughts.
190
Who is the lower Mekong River basin home to and what does it provide?
- The Lower Mekong River basin, which includes parts of Thailand, Laos, Cambodia and Vietnam.
- It is home to 60 million people who are dependent on agriculture (rice) and fisheries.
191
What adaptation plans were there to manage the river water in the lower Mekong in the face of climate change?
- It is important to manage the river water in the face of climate change, but by 2016 there were no transboundary plans.
- Only 11 per cent of national plans were linked to projects in the Lower Mekong.
192
What water conservation adaptation plans have been introduced in China?
- In northern China, water-saving irrigation has been introduced in areas of huge demand in a drying climate, in order to adapt to water scarcity and food security issues.
- Between 2007 and 2009 the country saved up to 11.8 per cent of its previous water consumption.
193
What resilient agricultural system adaptation strategies have been used in northern China?
- In northern China strategies of early or late planting can match climate change, using crops designed to withstand higher temperatures.
- For example, maize yields by 2050 could increase by 15.2 per cent.
194
What resilient agricultural system adaptation strategies have been used in northern Tibet?
- In northern Tibet, where alpine pastures are being degraded by higher temperatures and precipitation, a three-year demonstration plan made use of higher lake levels for irrigation during dry periods.
- This doubled grassland productivity and increased the number of plant species from 19 to 29.
195
How is land use planning used to adapt to the impacts of climate change?
- Areas of increased risk, such as from coastal or river flooding, can be zoned through urban planning and laws so that people and valuable property are not within them.
- Planning would also include the location and design of infrastructure to ensure its resilience to climate change factors such as stronger storms and higher water levels.
196
How is flood risk management used as an adaptation strategy to climate change in Australia?
- Australia is adapting to increased flood risk by making all housing on floodplains more flood resistant, with raised floors, stronger pile foundations and water resistant materials.
- Those living on floodplains are relocated.
- An ecosystem approach is used to retain floodplains in urban areas and use wetlands as overspill areas.
- Reservoir levels are closely monitored to anticipate inundations and release water at safe levels.
197
What are the problems with the flood risk management adaptation strategy in Australia?
- Issues include the high cost of relocating people.
- reduced property values in rezoned areas.
- locals contesting the changes.
198
What are some energy targets and policies for rebalancing the carbon cycle?
- Energy targets and policies include the development of:
- renewable energy sources.
- nuclear.
- carbon capture and storage (CCS).
- bio-energy with carbon capture and storage (BECCS).
- and switching from fossil fuels to renewables.
199
How can carbon emissions be reduced from the production to the end usage of fossil fuels?
- Reduced emissions can also be achieved through increasing energy efficiency in supply, transmission and distribution pathways.
- As well as developing combined heat and power (cogeneration) and controlling methane emissions.
200
How can transport of fossil fuels be more efficient in order to rebalance the carbon cycle?
- In transport there could be a switch to low-carbon fuels and biofuels, more efficient technologies (for example, lighter materials), smaller vehicles, journey avoidance, car sharing and eco-driving practices.
- In addition, businesses and governments can make infrastructure improvements to improve journey efficiency and move freight from road to rail.
201
How can industry be made more efficient in order to rebalance the carbon cycle?
- In industry, emissions can be captured (CCS) or processed.
- A switch made away from fossil fuel electricity to the use of BECCS or waste products would increase efficiency.
- Consumers also have their part to play, by moving away from a 'throwaway' society, sharing journeys, reducing demand, using goods more intensively (as in 'reduce, reuse, recycle, recover/repair').
202
What did the 2016 Climate Change Performance Index show about the performance of countries in trying to reduce emissions?
- The 2016 Climate Change Performance Index, based on 58 countries which together emit over 90 per cent of world CO2 emissions, showed that no country is performing well enough to reduce the impact of their emissions overall.
203
According to the 2016 Climate Change Performance Index which countries performed good/bad in trying to reduce emissions?
- Good performers included Denmark, the UK and Sweden, with European countries also doing well.
- The poorest-performing country was Saudi Arabia, with Japan, Australia and South Korea also performing poorly.
204
What does the 2016 Climate Change Performance Index consider when ranking countries?
- This index considers emissions, use of renewable energy, energy efficiency and government policies on climate change.
205
How successful have mitigation methods been across countries?
- Mitigation methods are progressing better in some countries than others, although the 2015 Paris Agreement may lead to greater urgency and action in the near future.
206
What are common mitigation measures to rebalance the carbon cycle?
- carbon taxation
- renewable switching
- energy efficiency
- afforestation
- carbon capture and storage (CCS)
207
How can government taxes cause people and businesses to reduce carbon emissions?
- Government taxes can encourage people and businesses to reduce carbon emissions by using less fuel or electricity.
- Specific taxes include congestion and emissions charges, road tolls and taxes on vehicles and vehicle fuels.
208
How can government taxes cause construction and industry to reduce carbon emissions?
- Construction and industry can be charged carbon taxes to encourage them to use environmentally friendly materials and minimise waste and emissions.
- Farming can have taxes on fertilisers, especially nitrogen (a greenhouse gas).
209
How is carbon taxation used in the UK as a mitigation strategy to rebalance the carbon cycle?
- In the UK, vehicle fuels are highly taxed.
- in 2016 taxes accounted for over half the cost of petrol and diesel.
- London has congestion and emissions charging zones, but at present no tax is payable on a car in the UK emitting less than 100 g/km of CO2
210
What is the UK's policy on renewable switching as a mitigation method?
- UK policy is based on switching away from fossil fuels to low-carbon energy sources.
- The UK established a target of 15 per cent of energy consumption by 2020 to be from renewables, including onshore and offshore wind, biomass electricity, biomass heat, air and ground heat pumps, and renewable transport.
211
What are the projected savings from renewable switchings in the UK in 2020?
- Projected savings in greenhouse emissions in 2020 could be 134 MtCO2.
- With over 65 per cent of these savings from renewable switching.
212
How is energy efficiency as a mitigation method used to rebalance the carbon cycle?
- Technological improvements mean that vehicle engines are more efficient.
- For example, between 1970 and 2008 the fuel efficiency of the average passenger car in the
USA improved by 57 per cent.
213
How are the UK improving energy efficiency as a mitigation strategy?
- Hybrid vehicles such as the 1,200 Routemaster buses in London are extending efficiency and reducing emissions.
- The UK government estimate that by 2020 its energy-efficiency policy should save the energy use of 9 million households, or the output of 19 power stations.
214
How is energy efficiency in the EU being improved to mitigate climate change and rebalance the carbon cycle?
- In the EU, household electrical items now
| use less electricity, being rated on an A-to-G scale with A+++ being the most efficient.
215
What afforestation schemes are being used to mitigate climate change?
- In addition to schemes such as REDD (Reduced Emissions from Deforestation and Forest Degradation), which pay forest owners not to cut down forests, afforestation is converting land that has not been forested for at least 50 years into a forest absorbing and storing large amounts of carbon.
216
How is afforestation being used to mitigate climate change in the Mapanda district in Tanzania?
- In Mapanda district
in Tanzania, over 3,500 ha of eucalyptus, pine and fruit trees have been planted on degraded grassland and on maturity will be used by local people.
217
How successful are afforestation mitigation methods expected to be in the future?
- It is estimated that between 2000 and 2020 this afforestation will have removed an average of over 166,000 tonnes of CO2 per year from the atmosphere.
218
How will carbon capture and storage (CCS) be used as a mitigation strategy to rebalance the carbon cycle?
- Large producers of CO2 could be forced to capture the gas before it is emitted into the atmosphere, compressing and storing it underground in disused oil and gas fields.
219
What was the first CCS mitigation scheme and what did it do to rebalance the carbon cycle?
- In 1996 the Sleipner project in the North Sea was the world's first CCS scheme.
- taking unwanted CO2 from natural gas and injecting it 3 km underground into a porous and permeable rock layer.
- Monitoring shows that it is securely confined.
220
What are future CCS mitigation plans to rebalance the carbon cycle?
- There are plans to transfer captured CO2 from mainland UK to the Auk and Goldeneye fields under the North Sea.
221
Why are agreements on mitigation strategies for climate change difficult to implement?
- Global-scale agreements and actions to rebalance the carbon cycle have proved slow to implement because countries put their own economic and political interests first.
222
What 3 spheres do the IPCC suggest are needed to rebalance the carbon cycle?
- Practical actions: that are observable and measurable, including implementation, monitoring and evaluation.
- Political actions: to set up systems and structure, such as legal and economic, so that practical action can be effective.
• Personal actions: to influence the political sphere by changing behaviours and responses, including systems to create capacity for change.
223
In the timeline of global action of climate change, what occurred in 1988?
- IPCC formed by UNEP and WMO to provide independent scientific advice on climate change.
224
In the timeline of global action of climate change, what occurred in 1992?
- Earth summit meeting, Rio de Janeiro, Brazil:
- Agenda 21 - everyone has individual and collective responsibility for looking after the planet, change consumption patterns to reduce CO2 emissions, and do more to protect the natural systems.
225
In the timeline of global action of climate change, what occurred in 1997?
```
- Kyoto Protocol - an international agreement that set targets for developed countries to cut and stabilise greenhouse
gas emissions (based on 1990 levels).
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226
What did the Kyoto Protocol agreement oblige countries to do?
- 38 countries, producing an estimated 55% of world emissions, agreed to reduce their CO2 emissions by between 5 and 8% by 2012 legally binding in 2005, but USA (20% of total emissions) did not sign.
- Developing countries not included and carbon trading was allowed.
- By 2007 172 countries had agreed to the protocol.
227
In the timeline of global action of climate change, what occurred in 2007?
- Comprehensive reports published by IPCC.
| - Nobel Peace Prize awarded jointly to the IPCC and Al Gore for informing the world about climate change.
228
In the timeline of global action of climate change, what occurred in 2014?
- Comprehensive
reports published by IPCC.
- Led to calls for all countries to reduce their CO2 emissions.
229
In the timeline of global action of climate change, what occurred in 2015?
- Paris COP meeting.
| - Target set to keep temperature increase below 2 degrees c, all countries to pledge to reduce their emissions.
230
How does calcium carbonate form in the ocean?
- Limestone rocks contain a high concentration of calcium carbonate.
- It is formed partly from the shells and skeletons of marine creatures, such as corals, that extracted the mineral from the seawater.
- It also forms from marine phytoplankton that absorb carbon through photosynthesis.
- The remains of these organisms accumulate on the seabed where over long periods of time they are cemented and compacted into organic limestone rock.
231
What 2 types of limestone rock can be formed?
- Chemical limestone can form from direct precipitation of calcium carbonate from salt or freshwater.
- Evaporite limestones can form from the evaporation of seawater, which leaves behind calcium carbonate deposits.
232
Why are limestone rocks vulnerable to chemical weathering?
- Rain becomes a weak carbonic acid when it falls through the air.
- It dissolves the calcium carbonate (a weathering process), allowing erosion processes to transfer dissolved carbon for deposition on the seabed.
233
What do geological concentrations of hydrocarbons represent?
- Geological concentrations of carbon compounds (carbon-hydrogen chains, or hydrocarbons) represent the remains of living organisms deposited during the formation of sedimentary rocks.
234
What will remains of land based plants eventually form?
- The remains of land-based plants may form peat and then coal;
- such conditions existed 300 mya in tropical coastal swamps that eventually formed major coal fields.
235
How long does the formation of coal take?
- The formation of coal takes tens to hundreds of millions of years, depending on temperatures and pressures.
236
What can high temperatures and pressures cause carbon in coal fields to produce?
- The highest temperatures and pressures concentrate carbon to produce anthracite, which has a high energy potential.
237
What % of carbon is needed in a material to create crude oil in a coal field?
- In order to produce crude oil the source material must contain about 2 per cent organic carbon.
238
How is organic carbon converted to crude oil in coal fields?
- Anaerobic reactions convert over 90 per cent of the organic carbon into a liquid - crude oil.
239
What happens to crude oil once it has formed in a coalfield?
- The crude oil moves or migrates, due to its lower density, into permeable or porous rock layers where it may be trapped within anticlines (upfolds) of impermeable rock.
240
What elements do crude oil contain?
- Crude oil contains about 85 per cent carbon and 13 per cent hydrogen.
241
What are the by-products of the formation of coal and crude oil?
- Natural gas, such as methane (CH4), is created as a by-product during coal and oil formation.
- It may be trapped within the same sedimentary rock layers as the crude oil.
242
What sedimentary rock can form shale oil and natural gas?
- Black shales contain organic material that may become shale oil and natural gas.
243
How does chemical weathering of carbon rich rocks cause transportation of minerals to the sea?
- Rainwater is a carbonic acid, absorbing CO2 from the air and then dissolving rock minerals to form new minerals such as calcium carbonate.
- Rivers carry these minerals to the sea, where they are deposited and buried, eventually forming new rock.
244
How can carbon rich sedimentary rocks release CO2 back into the atmosphere after the process of chemical weathering?
- Tectonic forces may bring carbon rich sedimentary rocks into contact with extreme heat, which causes chemical changes and the release of CO2 back into the atmosphere.
245
How do volcanoes release CO2 into the atmosphere?
- Volcanic activity at subduction zones, constructive plate boundaries or intra plate locations causes gases, including CO2, to be released into the atmosphere.
246
Where is outgassing of volcanoes common?
- Outgassing is common in geothermal areas, such as the CO2 - rich hot springs in Yellowstone, Iceland and New Zealand.
247
How much carbon dioxide is released by volcanoes every year?
- It is estimated that volcanic activity releases about 300 million tonnes of carbon dioxide every year.
- along with a tiny amount of carbon monoxide.
248
Which is the most common volcanic gas?
- The most common volcanic gas is water vapour.
- CO2 is the second most abundant.
- This is because CO2 is the least soluble of the volcanic gases and so is degassed earlier in eruption process.
249
How does outgassing or degassing take place in a volcano?
- Outgassing and degassing takes place through the main vent of a volcano, at hot spots or constructive plate boundaries.
- It often occurs with gases direct from the mantle, through porous flanks of volcanoes, or diffusion in geothermal areas including from lakes oversaturated with CO2.
250
How is carbon recycled at subduction zones of volcanoes?
- Carbon is recycled at subduction zones with carbonate rocks dragged into the mantle.
- Creating an upper mantle carbon concentration of between 50 and 250 ppm.
251
Where is carbon released in the subduction zones of volcanoes?
- CO2 is released at a shallow crustal depth at subduction zones.
- this release may have increased over the last 180 mil years as a result of biological evolution and the consequent deposition of more organic sediments.
252
Which volcano is the most actively degassing volcano in Europe?
- Mt. Etna in Italy is the most actively degassing volcano in Europe.
- probably because of the limestone and dolomite rocks from the Tethys Ocean underneath.
253
Which volcano is the most actively degassing volcano in the world?
- Popocatepetl in Mexico is the worlds most active degassing volcano.
- However, volcanic activity is intermittent and so the degassing has only short term effects of the atmosphere.
254
How does the timescale of the biological carbon cycle compare to the geological carbon cycle?
- The biological carbon cycle has a shorter timescale than the geological carbon cycle, measured from
days to thousands of years.
255
What is one of the main stores in the biological carbon cycle?
- One of the main stores (sinks) is the ocean, and there are significant fluxes due to photosynthesis and respiration.
256
What occurs during the process which is often called the carbon pump?
- Phytoplankton in surface waters use sunlight to turn carbon into organic matter through photosynthesis.
- Carbon enters the food web via other organisms that use carbon to make their shells and skeletons (calcium carbonate).
- such as corals, oysters, crabs and zooplankton.
257
How can using carbon from seawater be efficient?
- By using carbon from the seawater, more carbon dioxide can then enter the sea from the atmosphere, although some is returned through respiration.
- In this way, organisms move carbon from the atmosphere to the shallow ocean, and then to the deep ocean when they die and sink.
- This carbonate material accumulates on the seabed and eventually turns into sedimentary rocks (the marine carbonate pump).
258
Which areas of oceans have natural sources of methane gas?
- Oceans are a small natural source of methane gas (CH4).
- Especially shallow coastal offshore areas, where gas seeps from a nutrient rich seabed through the ocean to the atmosphere.
259
Why is the southern ocean around Antarctica an important carbon sink?
- Since colder water, and also deep water under pressure, can hold more gas than warm or shallow water, the Southern Ocean around Antarctica is an important carbon sink.
260
What % of diffusion of CO2 from the atmosphere to the ocean is the souther ocean responsible for?
- It has been estimated that the Southern Ocean accounts for 25 per cent of the diffusion of CO2 from the atmosphere to the oceans:
- the deep cold water rises very gradually to the surface, where it absorbs CO2 from the atmosphere.
261
Why may the southern ocean not be as much of an important carbon sink in the future?
- Some research suggests that the process of deep cold water rising to the surface may be slowing, which would mean that the Southern Ocean may not be such an effective carbon sink in the future.
262
How does the southern ocean show a physical carbon pump involving upwelling an downwelling currents?
- Cold, denser seawater sinks into the deep ocean, where slow-moving deep ocean currents hold the CO2.
- These deep currents eventually return to the surface, where the seawater is warmed and CO2 is diffused back into the atmosphere.
263
What is thermohaline circulation?
- The process of carbon compounds being transported between the world's oceans along the deep ocean conveyor.
264
How do ocean currents transfer heat energy?
- Ocean currents transfer heat energy with large gyres moving warm tropical water towards the poles, and colder water towards the equator.
265
What is the world scale thermohaline circulation driven by?
- The world-scale thermohaline circulation, which starts in deep ocean areas is driven by differences in density, with cold dense salty water sinking, and warmer water upwelling from intermediate depths to replace it.
266
How is the world scale thermohaline circulation beneficial?
- The world scale thermohaline circulation is beneficial as not only are nutrients, oxygen and heat brought to the surface, but also fresh CO2 to diffuse into the atmosphere.
267
Where is thermohaline circulation clearest?
- The thermohaline circulation is clearest in the Atlantic Ocean.
268
How do scientists estimate how long it takes deep ocean water to return to the surface?
- Radioactive carbon-isotope dating of deep ocean water shows that it takes hundreds, even thousands, of years, for deep ocean water to return to the surface.
269
Why does it take so long for deep ocean water to return to the surface?
- It takes so long because the flow rate is very slow, between 1 and 3 km per day due to its high density.
- However, the volume of water moving in the deep ocean is huge - about 400,000 km3
270
What do primary producers do?
- Primary producers (plants) absorb carbon dioxide from the atmosphere during the process of photosynthesis, and then release the gas back into the atmosphere through respiration.
271
How do plants use solar energy to allow growth?
- Plants use solar energy to change carbon dioxide and water into carbohydrates, which then allow the plants to grow.
- this process is greatest during the growing season and during daylight.
272
How do plants release CO2 into the atmosphere?
- As plants convert carbohydrates into energy during photosynthesis, respiration takes place and they release some of that energy, along with water and carbon dioxide, 24 hours a day.
273
Why are winter CO2 concentrations often higher?
- The exchange between plants and the atmosphere has a seasonal pattern, so that winter CO2 concentrations are higher.
274
How much CO2 is released into the atmosphere by plants compared to what is absorbed?
- Although CO2 moves in both directions, about 1,000 times more CO2 is taken out of the atmosphere than is released back into it.
275
How can deposition of litter impact CO2 concentrations in the atmosphere?
- CO2 is released during the decomposition of litter (dead leaves and twigs or humus) by soil biota, including microorganisms.
- Carbon structures are broken down and stored in the biomass of the biota or released.
276
How does organic matter content in soil impact its ability to store carbon?
- High organic matter content in a soil increases its ability to store carbon, but then soil biota may release more CO2 into the atmosphere.
277
How do wetland environments produce methane?
- Methane (CH4) is produced in wetland environments by anaerobic decomposition of organic matter and by termite digestive processes.
278
How does the amount of methane released into the atmosphere through terrestrial processes compare to carbon?
- The quantities are extremely small compared with carbon dioxide and vary spatially and over time.
- although methane is a more potent greenhouse gas.
279
Why is the earth often described as being in the 'goldilocks position' in the solar system?
- This is because in terms of temperature it is just right.
- The heat energy from the Sun has warmed the planet to a point that can support life.
- This is a natural process modified by the orbit and tilt of the Earth as it moves around the Sun over long timescales (Milankovitch cycles).
280
How does the earths atmosphere reflect solar energy from the sun?
- As the Sun's energy enters the atmosphere, clouds refiect some of it back, so that only about half of it reaches the Earth's surface and lower atmosphere.
281
Why does some of the suns solar energy pass through the lower atmosphere?
- This energy is able to pass through the denser gases of the lower atmosphere because of its short wavelength.
282
How is solar energy from the sun reflected from the earths surface?
- Heat energy is reflected back towards space from the Earth's surface, but at a longer wavelength.
- This means that it has difficulty travelling through the denser gases such as carbon dioxide and methane, and so the atmosphere absorbs the heat.
- This warms the lower atmosphere, the land and the sea, albeit with a range of temperatures from tropical to polar.
283
Without greenhouse gases what temperature would the earth be?
- Without the greenhouse gases such as water vapour, carbon dioxide and methane, the average temperature of the Earth would be -6°C rather than +15°C.
284
What is the present geological period called?
- The present period is the Holocene geological period.
| - It has had a relatively stable climate compared with the Earth's more distant past.
285
How have scientists been able to calculate temperatures of the earth during certain past time periods?
- Scientists in Antarctica and Greenland have analysed ice cores that extend back as far as 800,000 years.
- They worked out the temperature at particular times from the concentrations of gases and oxygen isotopes trapped within them.
286
What did scientists find when analysing ice cores to find previous global temperatures?
- They have found a strong positive correlation between the concentration of carbon dioxide and methane and temperature, which corresponds to ice ages and inter glacial periods in the Earth's geological history.
287
Since when have anthropogenic emissions altered levels of greenhouse gases?
- Up until about 1750, natural geological and biological processes controlled the levels of greenhouse gases in the atmosphere, but after this date anthropogenic emissions have altered natural stores and fluxes.
288
How are carbohydrates created in the cells of autotrophs via photosynthesis?
- Carbohydrates are created in the cells of autotrophs by combining carbon dioxide, water and light energy from the Sun.
- Carbon dioxide is consumed during this process and oxygen is produced.
289
How does respiration of autotrophs balance photosynthesis?
- The process of respiration balances photosynthesis by producing energy when combining oxygen with the carbohydrate and releasing carbon dioxide and water.
- Photosynthesis and respiration both cycle CO2 and 02 between oceans, the atmosphere and the biological world.
290
How stable was the carbon cycle before the industrial revolution?
- Before the Industrial Revolution, the fast fluxes or exchanges of carbon were fairly constant and the carbon cycle was balanced.
291
How have humans impacted the speed of fluxes and exchanges in the carbon cycle?
- Human activity has transferred considerable amounts of carbon from fossil stores, where exchanges are very slow, into the fast category, significantly disturbing the climate cycle.
292
How is the warming rate of our climate now, different to the warming rate after the ice age?
- Whereas after an ice age it usually took the planet about 5,000 years to warm up again (by 4 to 7°C), the present warming rate is estimated to be eight times faster than previous changes.
293
What evidence has the IPCC collected on natural forcing of heat and what does it show about the current warming rate?
- The IPCC has been collecting evidence of natural forcing of heat, such as Milankovitch cycles, Sun cycles, El Nino, ocean oscillations and volcanic activity.
- none of these account for the recent rapid warming of the Earth.
294
How do CO2 levels in our atmosphere now, rank against previous levels?
- The concentration of
CO2 in the atmosphere is increasing with levels now higher than ever before (when compared to bubbles of air trapped in Antarctic ice going back 800,000 years).
295
How are fossil fuels contributing to the rising CO2 levels?
- CO2 enters the atmosphere when fossil fuels, extracted from the geological store are combusted to provide energy for human activities such as transport and electricity production.
- This process has continued since the Industrial Revolution and accelerated through the oil age, changing the chemistry ofthe atmosphere.
296
How does the range of values for CO2 concentration across time in the atmosphere vary to now?
- Before the Industrial Revolution, the CO2 concentration in the atmosphere had varied between 180 ppm and 290 ppm over the previous 2 million years, the highest level being after the last ice age.
- However, in 2016 the concentration passed 400ppm.
297
By how much has the IPCC estimated CO2 concentration to have increased between 1750 and 2011?
- The IPCC estimates that between 1750 and 2011 the concentration of CO2 in the atmosphere increased by 40 per cent.
298
How much carbon have fossil fuels and deforestation added to the atmosphere?
- The combustion of fossil fuels has added 375 PgC to the atmosphere and deforestation has added 180 PgC.
299
How has the carbon cycle absorbed the increase in carbon from fossil fuels and deforestation?
- The carbon cycle has absorbed this quickly in different ways, with 240 PgC going into the atmosphere, 155 PgC into the oceans and 160 PgC into terrestrial ecosystems.
300
How long will CO2 emissions stay in the atmosphere for?
- Between 15 and 40 per cent of the CO2 remains in the atmosphere for up to 2,000 years, so climate change will continue for some time to come.
301
How much have CO2 emissions from fossil fuels increased since 2000?
- CO2 emissions from fossil fuels have increased by over 3 per cent a year since 2000.
- This is with a temporary reduction which resulted from the world financial crisis of 2008.
- Emissions related to land use change have been slowly decreasing over recent decades.
302
8 possible implications for the climate of a 2 degrees celsius temperature increase?
• Atlantic and Southern Ocean thermohaline circulation may weaken, altering the transfer of heat by oceans.
• Antarctic ice shelves will melt, adding more freshwater to the Southern Ocean, changing density and convection.
• Extratropical low-pressure-system (depressions) tracks will move northwards with climate pattern shift.
• Temperate and tropical zones may experience stronger storm activity as a result of more heat energy and moisture in the atmosphere, including more intense tropical cyclones and stronger mid-latitude westerly winds.
• Precipitation will increase in higher latitudes and decrease in lower latitudes. Worldwide patterns will change, with wetter eastern parts of North and South America, northern
Europe and northern and central Asia.
• The Sahel, the Mediterranean, South Africa and South Asia will become drier, with drought more common in the tropics and subtropics - but some uncertainties remain, as there are multiple factors (such as El Nino).
• The hottest year on record was 2015, with the average world temperature 1°C above that of the pre-industrial era; 2011 to 2015 were the hottest five years on record. The number of cold days and nights will decrease, and warm ones will increase. There have been fewer extreme cold events over the last 50 years, but more extreme heat events.
• The average Arctic temperature has already increased at twice the global average over the last 200 years. Snow and ice cover will contract with the ablation of glaciers.
303
5 possible implications for ecosystems of a 2 degrees celsius temperature increase?
• Habitat changes will mean 10 per cent
of land species with limited adaptability
will face extinction as the climate gets warmer and either wetter or drier. Rates of extinction could rise to 15 and 40 per cent of all species, especially in high - risk polar regions. Arctic and Antarctic fauna will be affected (e.g. polar bears, caribou, emperor penguins, gyrfalcons, lemmings, snowy owls, rainbow trout).
• Biodiversity will be affected as habitats shift poleward or into deeper ocean waters or higher altitudes. In north Brazil and central-southern Africa, lower rainfall and soil moisture, which cause changes to soil and oxygen, will reduce biodiversity. Tundra biome will be affected by thawing permafrost.
• By 2080 shifting temperatures may reduce bird habitats in North America, affecting 314 species, with ocean and coastal habitats a ected the m ost (e.g. Pacific golden plover), also partly because of coastal flooding and salt encroachment.
• Butterflies are a good example of the shift northwards of climate zones (6.1 km per decade). Marine diversity may be lost as sh move away from warming sea temperatures and about 80 per cent of coral reefs could be bleached (e.g. the Great Barrier Reef). Acidi cation of seawater (carbonic acid) will threaten corals and the shells of marine creatures will get smaller and thinner.
• Plant changes will lag behind animal changes, as they cannot move, and they will face pests and diseases where there is less cold weather to kill them.
304
7 possible implications for ecosystems of a 2 degrees celsius temperature increase?
• Rivers will dry up in regions where precipitation is reduced or less effective
because of higher evaporation rates.
• A shift of subtropical high pressure areas northwards will cause a 20 to 30 per cent decrease in water availability in Mediterranean climate zones.
• Small glaciers will disappear (e.g. in the Andes and Himalayas), decreasing river discharges once they have gone.
• Humidity levels in the atmosphere will increase, consistent with what warmer air can hold.
• Extreme heavy precipitation events will become common, with precipitation increases over northern-hemisphere land areas.
• Uncertainty remains over increased river flooding, since multiple factors are involved, but more ash flooding is likely as a result of more intense precipitation.
• Permafrost areas will thaw and add more water to Arctic rivers.
305
What % of anthropogenic greenhouse gas emissions are emitted as carbon dioxide (fossil fuels and industry) in 1970, 1990 and 2010?
1970 - 55%
1990 - 59%
2010 - 65%
306
What is the energy mix of a country?
- The energy mix of a country is the proportion of each primary energy resource it uses in a year. These resources may be both produced within the country (domestic) and imported.
307
What has the global energy mix been dominated by for a long time?
- The global energy mix has been dominated for a long time by non-renewable fossil fuels, especially crude oil and coal.
308
How is the global energy mix expected to change in the future?
- In the future it is expected that coal and oil use will decline, and that renewable energy resources will increase.
- This move away from dependence on non-renewable energy resources, such as carbon-rich fossil fuels, to less polluting and more sustainable energy resources, has the common aim of achieving a lower carbon energy mix.
309
Why will the energy transition towards a more sustainable energy mix be slow?
- The energy transition may be relatively slow, as new technologies need to be developed and current energy pathways, with trade based on established geopolitical links, are not easy to break.
310
What is primary energy?
- Primary energy refers to natural energy resources that have not been converted into another form of energy.
- It includes non-renewable resources such as fossil fuels (crude oil, coal, natural gas) and nuclear (uranium).
- and renewables such as hydro, biomass/biofuels, solar and wind.
311
What is secondary energy?
- Secondary energy refers to what the primary source has been converted into, usually electricity.
- The term 'power generation mix' refers to the combination of energy resources used to create electricity.
- In May 2016 the UK, for the first time, managed to provide all its electricity needs without using coal.
312
What 7 factors does the energy mix of a country depend on?
1. The availability of primary energy resources within the country, including levels of technology to extract and use them.
2. The accessibility of primary energy resources from outside the country.
3. The real or perceived energy needs of the country, based on lifestyles, economic development
and climate.
4. Changing energy consumption patterns, perhaps linked to population or economic growth.
5. National and regional policies that a ect energy production and consumption, such as
legislation related to the natural environment (climate change targets) or the social environment
(un employment).
6. Cultural and historical legacies regarding energy use and geopolitical links.
7. The financial costs of each energy option.
313
Which region has the largest oil reserves and oil production?
- As a result of the region's specific geological circumstances, the Middle East has the world's largest
oil reserves and the largest production.
314
Why are Russia and USA also major oil producers along with the Middle East?
- Russia and the USA are also major oil producers, partly because of the high demand from their industries and transport.
315
Which developing countries have significant oil reserves?
- Some developing countries such as Venezuela, Mexico and Nigeria also have significant oil reserves; revenue from oil exports can help their economic development.
316
Where are the biggest trading pathways for oil?
- The biggest trading pathways are into Europe and the USA, the largest consumers of oil due to the many vehicles and industries and many wealthy consumers who can afford to use the resource.
317
What future problems exist over drilling in deep water for oil?
- Future problems exist over drilling in deeper water, such as the Arctic Ocean, and fracking (where gases and oil are forced out of rock layers);
- Both are controversial because of possible negative environmental impacts such as oil spills and ground subsidence.
