Carbon Cycle & Energy Security Flashcards
Carbon cycle definition
The biochemical cycle by which carbon moves from one sphere to another. It acts as a closed system made up of linked subsystems that have inputs, throughputs and outputs.
Energy security definition
The uninterrupted availability of energy sources at an affordable price, while meeting the sustainable environmental and economic needs
Define anthropogenic climate change
caused by human activities
What is a flux
Movements of Organic compounds through an ecosystem
What is sequestration
The natural storage of carbon by physical or biological processes
List the aspects of the carbon store in order of PgC Average
- Crustal/terrestrial geological (100,000,000)
- Deep Ocean (38,000)
- Terrestrial soil (1500)
- Surface Ocean (1000)
- Atmospheric (560)
- Terrestrial ecosystems (560)
Explain the geological store of carbon
- Most of the earths carbon is geological,
resulting from the formation of
sedimentary rocks - Slow geological processes release
Carbon into the atmosphere - Processes such as Mechanical,
Chemical and Biological weatheringProcess
Decomposition: Plant and animal particles that result from decomposition after death and surface erosion store carbon
Transportation: Rivers carry particles to the Ocean, where they are deposited
Sedimentation: Over millennia these sediments accumulate
Metamorphosis: The layering and burial of sediment causes pressure to build, which eventually becomes so great sediments are changed into rock – shale becomes slate
Explain the deep oceanic carbon store
Most carbon is dissolved inorganic carbon stored at great depths, very slowly cycled
Explain the Terrestrial soil carbon store
- From plant materials (biomass); micro-organisms break most organic matter down to
co2 in a process that can take days in hot, humid climates to decades in colder
climates - Micro-organisms and detritus feeders such as beetles feed on waste material from
animals, and this becomes part of these micro-organisms
Explain the Oceanic surface store
- Exchanges are rapid with the atmosphere through:
Physical Processes
- This is based on the oceanic circulation of water including
upwelling, downwelling and the thermohaline current
- The Colder the water, the more potential C02 can be absorbed
- Thus, warm tropical waters release C02 into the atmosphere,
whereas colder high - latitude oceans take in CO2 from the
atmosphere
Biological Processes
- This is the organic sequestration of CO2 to oceans by
Phytoplankton. These microscopic, usually single-celled, marine
plants float near the ocean surface to access the sunlight to
photosynthesise - Huge numbers make up half the planets biomass
- Carbon is then passed up the food chain by consumer fish and
zooplankton, which in turn release CO2 back into the water and
atmosphere
Explain the atmospheric carbon store
- CO2 and CH4 store carbon as greenhouse gasses with a
lifetime of up to 100 years
Explain the Terrestrial ecosystems carbon store
- CO2 is absorbed by the producers via photosynthesis
- Carbon is stored organically
- Animals consume plants and carbon compounds travel
through the food chain,
released via respiration. The animal dies and is eaten by
decomposers which return the carbon to the atmosphere.
What is the importance of the Geological Carbon Cycle
Geological Processes are an important control on the carbon
cycle
Through a series of chemical reactions and tectonic activity
The geological part of the carbon cycle interacts with the rock
cycle
Explain Chemical Weathering in terms of the Geological Carbon Cycle
Chemical weathering: in the atmosphere, water reacts with
atmospheric CO2 and carbonic acid forms. Once this water
reaches the surface as rain, it reacts with some surface minerals,
slowly dissolving them into their component ions
Transportation of calcium ions by rivers from the land into
oceans. These combine with bicarbonate ions to form calcium
carbonate and precipitate out as minerals such as calcite
Deposition and burial turns the calcite sediment into limestone
Subduction of the sea floor under continental margins by tectonic
spreading
Some of this carbon rises back up to the surface within heated
magma, then is degassed as CO2 and returned to the
atmosphere.
Explain volcanic outgassing in terms of the Geological Carbon cycle
Pockets of CO2 exist in the Earth’s. Disturbance by volcanic eruptions or earthquake activity may allow pulses or more diffuse fluxes into the atmosphere
Outgassing occurs at:
Active or passive volcanic zones associated with tectonic plate
boundaries, including subduction and spreading ridges
Places with no current volcanic activity, such as the hot springs
and geysers
Direct emissions from fractures in the Earth’s crust
Explain Thermohaline Circulation
Thermohaline circulations are a vital component of the global
ocean nutrient and carbon cycles. The movement of seawater in
a pattern of flow dependent on variations in temperature, which
give rise to changes in salt content and hence in density.
Process
The main current begins in polar oceans where the water gets
very cold: sea forms; surrounding seawater gets saltier,
increases in density and sinks
The current is recharged as it passes Antarctica by extra cold
salty, dense, water
Division of the main current: northward into the Indian Ocean and
into western Pacific
The two branches warm and rise as they travel northward, then
loop back southward and westward
The now-warmed surface waters continue circulating around the
globe. On their eventual return to the North Atlantic they cool,
and the cycle begins again
Explain the three factors that determine the carbon capacity of soil
- The capacity of soil to store carbon is determined by three factors: Climate, soil type and management/use of soils
Climate
- Dictates plant growth and microbial and detritivore activity.
- Rapid decomposition occurs at higher temperature or under
waterlogged conditions. - Places with high rainfall have increased potential carbon storage
than the same soil type in lowerSoil type
- Clay-rich soils have a higher carbon content than sandy soils.
- Clay protects carbon from decomposition.
Management and use of soils
- Since 1850, soils globally have lost 40-90 billion tonnes of carbon
through cultivation and disturbance.
What is the importance of the greenhouse effect, photosynthesis and soil health in regulating the carbon cycle
- The natural greenhouse effect is vital in regulating earth’s
temperature and precipitation, but anthropogenic climate
change has altered the balance of carbon pathways and stores,
having implications on climate, ecosystems and the hydrological
cycle - Ocean and terrestrial photosynthesis regulate the composition of
gases in the atmosphere. - Soil health is influenced by stored carbon which is vital for
ecosystem productivity.
Explain the greenhouse effect
The earth has a natural temperature control-system that relies on greenhouse gasses: its climate is driven by incoming shortwave radiation:
31% is driven by clouds, aerosols and gases in the atmosphere
Remaining 69% is absorbed – with almost 50% absorbed by the
Earth’s surface: especially by oceans
70% of this surface absorption itself is re-radiated to space as
longwave radiation
However, a large proportion of this longwave radiation emitted by the surface is re-radiated back to the surface by clouds and greenhouse gasses. This trapping of longwave radiation in the atmosphere is the natural greenhouse effect
Explain how fossil fuel consumption is interfering with the Carbon Cycle
- Fossil fuels have been burnt at an increasing rate since the start
of the industrial revolution - Naturally, carbon in fossil fuels would flux very slowly into the
atmosphere through volcanic activity. Fossil fuel consumption
shifts this flow from slow to fast carbon cycling. - Oil, natural gas, and coal furnish most of the energy used to
produce electricity, run automobiles, heat houses, and power
factories - If burnt completely, the only by-product containing carbon would
be carbon dioxide - The extracting, processing and transporting of fossil fuels also
leads to further carbon release. These releases can be
deliberate, as when natural gas is flared from oil wells, emitting
mostly carbon dioxide and methane. But they can also be from
poor maintenance and small leaks. - Methane occurring naturally in coal seams as pockets of gas in
the coal itself is released when coal is mined or pulverized.
Explain how deforestation is interfering with the Carbon Cycle
- Second largest source of carbon dioxide
- When forests are cleared for agriculture or development, most of
the carbon in the burned or decomposing trees escapes to the
atmosphere - An important part of the terrestrial carbon cycle
Explain how domestic animals are interfering with the Carbon Cycle
- The second-most important greenhouse gas after carbon
dioxide, methane is produced by cattle dairy cows, buffalo, goats - 100 million tonnes a year
Explain how rice cultivation are interfering with the Carbon Cycle
- Wetland or paddy ice farming produces one-fifth of all global
methane emissions from human activities - Bacteria and other micro-organisms in the soil of the flooded rice
paddy decompose organic matter and produce methane
What are the 4 human activities that are interfering with the carbon cycle
- Fossil Fuel consumption
- Deforestation
- Domestic Animals
- Rice cultivation
What is primary energy
Primary energy sources are the natural sources found in the earth, such as coal, oil and gas.
What is secondary energy
Secondary energy converts these sources into other forms, such as electricity for convenience
What is a rich energy mix made up of
- A rich energy mix is made up of domestic and foreign sources; a
country will have its own energy sources as well as importing
from other nations; having a diverse mix of renewable and non-
renewable sources
Explain what factors a country will depend on for access and consumption of energy recourses
Physical Availability: Fossil fuels, solar, wind, tidal and geothermal power depend upon location. Large power stations require flat and stable land to function correctly.
Cost: As supply decreases, costs increase. Prices are constantly fluctuating. Onshore oil deposits tend to be cheaper than offshore sights.
Technology: New technological developments have allowed oil to be extracted from deeper and more technically difficult environments. E.g. tar sands in Venezuela and Canada
Public Perception: There are cultural preferences around the world, some may be reluctant to adapt to new technology.
Levels of economic development: France can afford 78% of its energy to come from nuclear sources whilst poorer regions, such as Ethiopia, use sources like dung and crops for energy
Environmental priority: Costa Rica obtained 99% of its energy from renewable sources in 2015 as they are conscious of their environmental footprint
Describe the energy mix of North America
- Oil (40%) - vast reserves in Gulf of Mexico/ Alaska/ Canada
- gas (25%) - abundance
- coal (25%) - abundance
Its economic growth is due to these fossil fuels, which are consumed by industries such as the pharmaceutical, chemical, domestic use and transport sector
- North America has more nuclear reactors than any other country
(103) – has huge uranium reserves
-Less than 10% comes from HEP - most stations located on the East
and West coasts where there is plenty of rainfall and fast-flowing
rivers
Describe the energy mix of South & Central America
Oil + Natural gas (65%) - vast reserves of both fuels in Venezuela and pipelines and oil tankers connect these supplies in the Middle East to the rest of the region
- Greatest consumer of HEP due to heavy rainfall, fast-flowing rivers
and large dams e.g. in Brazil, Paraguay and Argentina - Consumption of coal and nuclear minimal – deficits in coal and
uranium reserves
Describe the energy mix of Brazil
- Energy mix dominated oil and HEP
- Oil (48%)
- HEP (35%)
- Largest sugar cane producer in the world, predominately used in the
production of ethanol fuel - Has the 6th largest Uranium reserves in the world – yet only has one
nuclear reactor - Third largest Hydro-electric producer, HEP provides 80% of the
country’s electricity supply - Co-owns the Itaipu HEP plant on the Parana River, located on the
border between Brazil and Paraguay, which is the world’s second
largest HEP plant
Describe energy mix of the Middle East
- Consumed mainly fossil fuels – oil provides 50% of energy needs
and gas 45% - huge reserves in Saudi Arabia, Iran, Iraq and Kuwait - Small amount of coal
Describe the energy Europe and Eurasia
- Europe and Eurasia’s consumption shared equally by oil and
natural gas (65%) – reserves of natural gas in Russia, UK and
Norway - 20% - coal - supplied by nations such as Poland, UK, Kazakhstan
coal is cheap and traditional – huge amounts of infrastructure
available for the production of coal - 10% of energy used comes from Nuclear power as Western
Europe can afford to import uranium - France, Kazakhstan and
Uzbekistan have reserves of uranium.