The Carbon Cycle and Energy Security Flashcards
Define adaptation strategies
An approach to respond to future impacts of climate change
- What is carbon?
It is a chemical element that exists in its pure form or as a combination with other elements e.g. CO2
It forms the ‘building blocks’ of all life on earth and is moved around the earth via the carbon cycle.
Why is carbon so important?
- Economic development relies on fossil fuels
- Energy scarcity has led to hardship and conflict
- Combustion of carbon is changing the environment
- A desire for carbon is destroying ecosystems
What is the carbon cycle?
It’s a closed biochemical cycle that moves carbon between the different spheres of the Earth
What are the four spheres of the Earth?
- Lithosphere (largest)
- Hydrosphere
- Biosphere
- Atmosphere
How is carbon stored?
- Inorganic, found in rocks as bicarbonates and carbonate
- Organic, found in plant material
- Gaseous, e.g. carbon dioxide, methane, carbon monoxide
How is carbon stored in the biosphere?
In living and dead organisms
How is carbon stored in the hydrosphere?
As dissolved CO2
How is carbon stored in the lithosphere?
As carbonates in limestone and fossil fuel e.g. coal, oil & gas
How is carbon stored in the atmosphere?
As gases like CO2 and methane
What is carbon sequestration?
When carbon is captured from the atmosphere and stored e.g. through photosynthesis.
Define combustion.
The burning of fuels such as wood and coal, releasing CO2 into the atmosphere
Define decomposition
When organic substances are broken down into simpler matter i.e. they rot.
Define photosynthesis.
When plants remove CO₂ from the atmosphere to create carbohydrates for plant growth.
(CO₂ is stored in the structure of plants – also known as carbon sequestration.)
Define respiration.
When a plant/animal releases CO₂
Define ocean uptake.
When oceans absorb CO2 from the atmosphere.
- What are examples of fast carbon fluxes?
(seconds to minutes)
- Photosynthesis
- Respiration
What are examples of medium speed carbon fluxes?
(10-500 years)
- Decomposition
What are examples of slow carbon fluxes?
(millions of years)
- Sedimentation/lithification
Is the geological carbon cycle slow or fast? What is the reservoir turnover rate?
Slow.
Reservoir turnover rate of at least 100,000 years.
Is the biological carbon cycle slow or fast? What is the reservoir turnover rate?
Fast.
Reservoir turnover rate of a few years to a few millennia.
Define reservoir turnover.
The rate at which carbon enters and leaves a store is measured by the mass of carbon in any store divided by the exchange flux.
What are the main stores in the geological carbon cycle?
Rocks and sediments
What are the main stores in the biological carbon cycle?
Vegetation, soils, atmosphere, water
What are some examples of geological stores of carbon?
- Limestone (sedimentary carbonate rock made from when shell-building organisms form layers and turn into rock)
- Coal (a fossil fuel, biologically derived from decayed organisms)
- Shale (sedimentary rock, biologically derived from organisms embedded in mud)
- The Himalayas
- Coral (organisms cemented together over time to form limestone structures – coral reefs)
What exactly are sedimentary carbonate rocks made out of?
Calcium carbonate - CaCO₃ - shells and skeletons of marine creatures
By what process do marine sediments become sedimentary carbonate rock?
Lithification
What mountain range represents one of the earth’s largest carbon stores?
Himalayas
What % of carbon-containing rock in the ocean is biologically derived?
20%
How long ago did fossil fuels form in the UK?
320 millions years ago
What are oil and gas made out of?
Microscopic organisms called plankton