Lesson 16 - Uncertain Future Flashcards
Which 4 primary factors are responsible for an uncertain future?
Physical
Human
Peatlands
Permafrost
How do terrestrial sinks contribute to an uncertain future?
Saturation reverses function
Begin to act as sources
How is the projected increase in terrestrial sinks currently modelled?
Generally increase until 2050
Why have oceanic sinks experienced reducing sink capacity?
Warming decreases CO2 solubility
Less CO2 uptake
Inefficient biological pump
What are the main human factors that contribute to future uncertainty?
Economic growth
Population change
International governance
Energy sources
How did the GFC contribute to uncertainty?
Concerns CO2 emissions would follow GDP recovery
Didn’t quite materialise
How do population characteristics affect uncertainty?
Changing diets + mobility
Liable to worsen emissions
Why are peatlands such significant carbon sinks?
Low rate of decomposition in cold/waterlogged soils
How does warming affect peatlands?
Water tables fall
Peat dries out
Decomposition accelerates
Net methane release
How do peatlands affect global emissions?
Burning, draining + degrading emits more than 10% of global FF emissions
Why is peatland restoration a contentious topic?
Rate of restoration unknown
Could drastically improve sequestration
How much carbon does permafrost contain globally?
1672 Gtc
Which physical factors affect the uncertainty of permafrost?
Talik development
Active layer depth
Melting
What is the range of estimated permafrost loss?
7-88%
How does active layer depth affect permafrost?
Increasing depth heightens emissions
Depends on feedback
