The biological carbon pump Flashcards
How many pathways in the BCP?
- Gravitational pump
- Physical pumps
- Biological pumps
What does the BCP include?
All the process in the ocean that cause organic carbon formed photosynthetically by phytoplankton in the sunlit surface layer to be removed from contact with the atmosphere
How long does the BCP sequester CO2 for ?
weeks up to millions of years
Does the BCP take up anthropogenic CO2?
No
What is the physical carbon pump?
Dissolution of CO2 into the cold polar/subpolar waters, the sinking of this CO2
How much of the CO2 has been absorbed by the southern ocean?
Half
What is the viscous cycle?
The fraction of CO2 emissions that the ocean is able to absorb may decrease if the observed intensification of the Southern ocean winds continues
What is BCP mediated by?
Physical processes such as eddies and mixing
What is active flux?
Animal movements
What is passive flux?
Physically driven through mixing
What are the types of sinking material?
- Dead cells
- Cell fragments
- Aggregates
- Faecal pellets
- NB food web processes
Martin curve
the flux of sinking organic C decreases rapidly with depth
What happens to the timescale of removal when the organic carbon is transferred deeper?
Increases
What controls atmospheric CO2?
Interior respiration
What is the mesopelagic migrant pump?
Organisms feed at the surface at night and spend the day at depth to avoid predation, active transport
