carbon EQ1 Flashcards
(68 cards)
What is carbon
An chemical element with a simple atomic structure that has the ability to bond with other elements
Relates complex molecules which are the basis of living matter
Why does plant life rely on carbon
It is necessary for photosynthesis
What are the 4 main carbon stores, and what form does carbon take in each
The atmosphere - as CO2 and CH4
The hydrosphere - dissolved as CO2
The lithosphere - as carbonates in limestone and fossil fuels such as coal oil and gas within rock
Biosphere - in living and dead organisms
What is the largest flux of carbon
Photosynthesis
What is the smallest flux of carbon
Volcanic eruption
What is a dynamic equilibrium of carbon
A situation in which the total amount of carbon entering a system is balanced by the total amount of carbon leaving
What causes variation in the dynamic equilibrium of the carbon cycle
Natural variation through forest fires and climate
Main variation is fossil fuel combustion and land cover Change
What are deep ocean hydrothermal vents
Fissures in the planets surface which issue geothermally heated water and minerals
Commonly fund close to tectonic margins especially divergence at mid ocean ridges or hotspots
How often does the entire ocean circulate though hydrothermal vents
Every 40 million years
What is known as the slow carbon cycle
Geological cycle
What is the geologic carbon cycle
The cycling of carbon through rock in the lithosphere taking millions of years
What is the geological carbon cycle driven by?
Tectonic movement, mountain building, weathering and erosion
What is released from rocks from weathering and erosion? What happens to it?
Calcium and bicarbonate
Washed into sea and used to form shells
Returned to a rock store when creatures die through sedimentation and burial of organic and inorganic carbon compounds
How many tonnes of carbon move through geological cycle annually
10-100 million tonnes of carbon annually
How is carbon released to the atmosphere from the lithosphere
-released during subduction
- Emitted in volcanoes outgassing
Describe chemical weathering
Atmospheric co2 combines with water vapour to form weak carbonic acid
- acid dissolves rocks and released calcium and other minerals
What is outgassing
To release or give off a gas
What is sedimentation
Process of settling or being deposited as sediment
What is precipitation in carbon
Causes a substance to be deposited in solid form from a solution
How do humans influence geological carbon cycle
Temperature increase from climate change Accelerates chemical weathering process
Poor land practice increase erosion rates - adding more carbon to rivers which can be deposited on the ocean floor where sedimentation occurs
How does negative feedback work in rebalancing the carbon cycle
Increased volcanic activity means increase in co2 emissions and loss of carbon from rocks
Temperature rises so more uplift of air, more rain
So more chemical weathering and more ions deposited on ocean floors
So more carbon stored in rocks
How and why do carbon fluxes vary between day and night?
During the day fluxes are positive from the atmosphere to the ecosystem due to photosynthesis
At night it’s negative as plants respire rather than photosynthesise
which land based eccosystem sequesters the most carbon, and what % does it sequester
The Amazon rainforest sequesters 17% of all terrestrial carbon
more than any other land based biome
Why is the Amazon so significant in carbon;sequestration
Intense sunlight and dense vegetation so efficient photosynthesis
Warm, moist climate leads to rapid decomposition and absorption by roots fixing carbon in the biomass of plants and trees