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Flashcards in Carbon Cycle Deck (64)
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1
Q

How do humans release carbon?

A

Combustion of fossil fuels
Deforestation
Industry
Transport

2
Q

How is carbon released naturally?

A
Acid rain
respiration 
evaporation/transpiration
volcanic activity 
(natural processes have the largest flow of carbon)
3
Q

Types of carbon

A

Geological and biologically derived carbon

4
Q

How much CO2 was released from the Icelandic eruption?

A

300 000 tonnes per day

5
Q

What does sequested mean?

A

naturally stored

6
Q

What are long term stores of carbon?

A

Crustal/terrestrial/geological=> sedimentary rocks, very slow cycling over millennia
Oceanic (deep) =>most carbon is dissolved, inorganic carbon stored at greater depths, very slow cycle

7
Q

What are short term stores of carbon?

A

Terrestrial soil=> microorganisms break most organic matter down into CO2 from biomass
Oceanic (surface)=> CO@ dissolves into the water and phytoplankton photosynthesises releasing carbon, making the exchange very rapid
Atmospheric=> greenhouse gases are stored such as CO2
Terrestrial ecosystems=>CO2 is taken in during photosynthesis and is stored in plants, especially trees, rapid exchange

8
Q

What key processes are involved in the carbon cycle?

A

weathering (mechanical, biological, chemical) decomposition
sedimentation (the formation of sedimentary rocks from the compaction of calcium carbonate from shells and skeletons of marine creatures)
transportation
metamorphism ( heat and pressure create metamorphic rocks)

9
Q

What implications are there for the earths climate if temperature increased by 2’C ?

A
  • Stronger storm activity, increased precipitations in higher latitudes, drought, sea level rise
    +Grow different types of crops, easier to travel via boats
10
Q

What implications are there for ecosystems if temperature increased by 2’C ?

A
  • 10% of land species will face extinction, reduced biodiversity, 80% of coral reefs could be bleached
11
Q

What implications are there for the hydrological cycle if temperature increased by 2’C ?

A
  • rivers will dry up, small glaciers will disappear decreasing river discharge
12
Q

Describe why GHG’s have increased since the Industrial Revolution

A

Decreased photosynthesis, increased respiration and increased fossil fuel consumption

13
Q

How are developing countries affected by global carbon emissions?

A

Latin America only contribute 12.5% of global carbon emissions, but will most heavily be affected by global warming
-precipitation may decline by 20-40%
more heat waves, desertification= reduced food availability

14
Q

What are the role of decomposers in the health of the soil?

A

Break down biomass so it can be stored as carbon in humus, improve the fertility of the soil, reduce limiting factors of plant growth by providing nutrients

15
Q

How much short wave radiation is reflected and how much is absorbed?

A

31% reflected by clouds and land surfaces, 69% absorbed by oceans

16
Q

What would the global average temperature be without the natural greenhouse effect?

A

-6’C

Global average temp is 15’C which is a life supporting temperature for a variety of flora and fauna

17
Q

How will climate change affect rainfall?

A

A warmer atmosphere can hold more moisture, wet regions get wetter, drier regions get drier,

18
Q

What is the energy mix?

A

The proportion of each primary energy resource it uses per year

19
Q

What factors does the energy mix depend on?

A

Availability, accessibility, energy needs, changing energy consumption patterns, national or regional policies, financial costs

20
Q

What is energy security?

A

The uninterrupted availability of energy sources at an affordable price

21
Q

Describe the UK’s energy security

A

-Could face blackouts, energy per capita has increased, relies on North Sea oil
+Increase in renewable energy
+Aims to reduce carbon emissions by 40% by 2030

=Although more renewable, Uk relies on imports making it energy insecure

22
Q

Describe Swedens energy security

A

-Reliant on fossil fuels of transport
+Mainly relies on HEP (high energy value and high power output) providing most of the population with electricity
+Aims to be carbon neutral by 2050

=energy secure on the whole

23
Q

What are the oceanic carbon pumps?

A

biological, carbonate and physical

24
Q

describe the biological carbon pump

A

CO2 is requested into oceans by phytoplankton. Phytoplankton float on the surface of the ocean to photosynthesise, and pass carbon along the food chain to consumers which release the CO2 by respiration

25
Q

describe the carbonate carbon pump

A

Calcium carbonate found in marine skeletons and shells sink to the sea floor either dissolving in the ocean or forming limestones sediments (e.g.. white cliffs of dover)

26
Q

describe the physical carbon pump

A

Colder waters can absorb more CO2 so CO2 concentration is 10% higher in deep water than surface water. Warm waters release more CO2.

Large ocean currents (North Atlantic drift) moves water from the tropics to the poles, absorbing more CO2

27
Q

How has human activity affected the carbon cycle?

A

Increasing demand for food and fuel
Deforestation
Oceanic acidification (role of carbon sink increasing)
Impact to soils (net decrease in carbon stored)
Combustion of fossil fuels
Foodchains and biomes disrupted (decline in coral reef health and marine ecosystems)

28
Q

What is geological carbon release?

A

Degassing of volcanoes, carbon recycled at destructive plate margins when carbonate is dragged into mantle

29
Q

How much CO2 does volcanic activity release?

A

300 million tonnes per year

30
Q

What is the most degassing volcano in Europe?

A

Mount Etna (due to dolomite and limestone beneath)

31
Q

How long does it take to form coal?

A

300 million years (in anaerobic conditions anthracite is converted into coal)

32
Q

Explain how terrestrial sequestration occurs

A

Fastest part of the carbon cycle, takes place in processes such as weathering, decomposition, transportation, sedimentation or metamorphism

The process is affected by climate and clycling, as it will happen much faster in tropical climates

33
Q

What impacts biological carbon in soils?

A

The topsoil horizons are most active in carbon cycling as hummus. Carbon can also be found in long term stores such as permafrost

Hummus soils are 60% carbon

34
Q

Factors that affect carbon in the soil

A

Soil type (clay=higher carbon content)
Management and use of soils (soils have lost 40-90 billion tonnes of carbon since 1850)
Climate (cold climates store 800 tonnes per hectare of carbon which is must higher than in arid climates)

35
Q

What is the holocene now being referred to?

A

the anthropocene due to the profound changes caused by humans

36
Q

How can an increase in carbon change global temperature?

A
Enhanced greenhouse effect
Increased temperature
loss of glaciers
loss of albedo, increases temperature
winters and colder and longer
oceans get warmer, marine life die
37
Q

How can an increase in carbon change global precipitation?

A

low pressure on the equator, little rainfall
drought
wet areas get wetter
more storms and hurricanes

38
Q

Which country has the highest total energy consumption?

A

China (3040 mtoe)

39
Q

Which country has one of the lowest total energy consumption?

A

France (243 mtoe)

40
Q

What energy players are there?

A

Energy TNC’s (Gazprom output in 2015 was 8.3 boe)
OPEC (control 81% of world oil reserves)
National governments (EU governments aims to reduce fossil fuel dependency)
Consumers (create demand and impact price/cost of fuels)

41
Q

Types of energy pathways

A

Bulk carrier ships (coal+uranium)
Trans-Alaskan pipeline (oil+gas)
Tanker ships (oil+LNG)
Underground electricity cables

42
Q

What are human obstacles for energy pathways?

A

Conflict between areas
Pirate activity
Embargoes (bans)

43
Q

What are natural obstacles for energy pathways?

A

Difficult terrain
Extraction from deep waters
Extracting from tar sands

44
Q

What is a choke point

A

Areas where key transport links can be easily disrupted

45
Q

Examples of choke points

A

Strait of Hormuz (approx 17 million barrels of oil pass through per day)
Strait of Malacca (77 piracy incidents in 2017)

46
Q

Political conflict of energy pathways

A

1)Russia vs USA for control over Syria
Many argue that the main reason for control over Syria is due to the proposed pipeline through Syria to fuel Europe

2)Russia is the biggest supplier of oil and wants share in European market
Russia allies with Iran who wants the same involvement
Iran wants to export its gas through Syrian pipelines, therefore it defends the Syrian government

47
Q

Positive impacts of US Shale gas

A

Economic
+ In the USA, the development of shale resources supported 600,000 jobs in 2010
+Provides of $4.4 billion in federal states
Political
+ Energy companies have been increasing the price of gas in order to convince the government to export to different counties
Environmental
+Carbon footprint of shale gas is half that of coal

48
Q

Negative impacts of US Shale gas

A

Economic
-chemical, manufacturing and steel industries may decline.
Environmental
-Releases methane and carbon dioxide which contributes towards global warming
-Increased risk of earthquakes
-Loss of habitats/biodiversity
Political
-Countries/states will start to become more reliant on US states with large supplies and extractions of shale gas as conventional fossil fuels start to run out, which could lead to conflict
Social
-Health risks from harmful substances, contaminated groundwater and air pollution

49
Q

How is Shale gas extracted?

A

Shale gas is trapped inside impermeable shale rocks
Hydraulic fracking involves forcing water mixed with chemicals into shale rock so that it splits apart and gas flows into a well

50
Q

How is shale oil extracted?

A

Oil shale can be mined, but must be heated to a high temperature to release the oil; its therefore very expensive.

51
Q

Positive impacts of Shale oil

A

Environmental
+Fossil fuels only account for 13% of Brazil’s energy mix- the oil helps to diversify the energy mix and to provide energy for where renewable supplies are intermittent (eg HEP during drought)

52
Q

Negative impacts of Shale oil

A

Environmental
-Water in Guanabara Bay is too polluted to swim in
-In 2000 1 million liters of oil was leaked into the bay which killed may species, plant species such as Mangroves still haven’t recovered
Political
-An estimated $2bn was siphoned off by politicians due to corruption
Social
-Local fisheries threatened by encroachment of oil industry

53
Q

Describe the extraction method of tar sands

A

Tar sands are a mixture of clay, sand, water and bitumen

The oil must be separated from the sands using very hot water diluted with lighter hydrocarbons

54
Q

Positive impacts of tar sands

A

Economic

+An expected $4trillion to go to the Canadian economy between 2015 and 2035

55
Q

Negative impacts of Tar sands

A

Environmental
-Landscape scarring due to mining process
-Damage to ecosystems
-8.5% of Canada’s greenhouse gases came from tar sands operations in 2013
-Estimated to contribute to global warming three times more than conventional oil
Social
-Local fisheries threatened
Economic
-Costs a lot of money to extract out of the ground

56
Q

Shale gas example

A

Barnett Shale, Texas
In 2007, the Barnett shale gas field produced 1.11trillion cubic feet of gas, making it the second-largest source of natural gas in the United States

57
Q

Shale oil example

A

Guanabara Bay, East coast of Brazil

Oilfield is 200-300km offshore

58
Q

Tar sands example

A

Alberta, Canada

166 billion barrels of oil found here

59
Q

what percentage of the UK’s energy is imported?

A

60% and theres only 50 years of coal left in the UK

60
Q

How is the Uk committed to decoupling the economy from fossil fuels?

A

> Increasing renewable energy
Develop a new generation of nuclear power stations
Reducing energy consumption
Recycling energy that would be wasted

61
Q

What is a strike price?

A

Where the government guarantees a minimum price per mega watt per hour (MwH)

62
Q

How long will Hinkley Point C nuclear power station provide energy for?

A

60 years

63
Q

How many homes will Quarrendon fields, Aylesbury supply? (wind power)

A

2000

64
Q

How much did Chapel lane solar farm (Christchurch) cost and how many homes does it supply?

A

£50 million
60,000 homes
Largest solar farm in the UK