Methane Gas Release Flashcards
What is methane primarily categorized as?
A powerful greenhouse gas
Methane occurs in the atmosphere mainly due to human activity.
What percentage of atmospheric methane concentration is produced by natural causes?
Just over 25%
Methane stores are highly sensitive to climate change.
What potential climate change event is associated with permafrost thawing?
Run-away climate change event
What is the relationship between atmospheric temperature and carbon gases?
Closely linked
A rise in carbon gas increases greenhouse gases, leading to accelerated warming.
What human activity is primarily responsible for the increase in atmospheric carbon dioxide?
Reliance on fossil fuel energy
What is the nature of the relationship between carbon and atmospheric temperature?
A two-way relationship
There is a correspondence rather than a clear cause and effect link.
How does increased temperature affect the solubility of carbon dioxide in oceans?
Reduces solubility
This increases the amount of carbon dioxide in the atmosphere.
What are the major storages (sinks) of carbon?
- Atmosphere
- Oceans
- Biomass
- Geology
What is the time scale of carbon fluxes?
From just a few hours to many millions of years
What is methane’s potency as a greenhouse gas compared to carbon dioxide over a 20-year period?
84 times more powerful
What percentage of human-induced global warming is attributed to methane?
20-30%
What percentage of atmospheric methane comes from anthropogenic influences?
75%
This includes agriculture, mining, and waste management.
Where does the majority of natural methane emissions originate from?
Wetlands
What percentage of wetland methane emissions come from tropical regions?
70%
What is a significant source of methane in the Arctic region?
Natural sources such as hydrate release
How quickly can methane emissions increase in a warming climate?
Rapidly with a small lag behind temperature change
What conditions lead to greater methane emissions in wetlands?
Increased water table and/or temperature
What significant risk is associated with global permafrost collapse?
Unlocking vast quantities of stored methane
How much methane is estimated to be stored in global permafrost?
1,400 gigatonnes
What was the estimated annual methane release from land-based permafrost in 2013?
17 million tons
What is a key positive feedback loop related to methane?
Loss of methane from the Arctic
What uncertainty exists regarding methane feedback in climate change?
Extent and time frame of positive feedback
What did a study led by Joshua F Dean find about old methane emissions during the last deglaciation?
Emissions from old carbon sources were small
What is a possible explanation for old methane being oxidized before reaching the atmosphere?
Microorganisms consuming thawing matter
