Claim: While methane is a more potent greenhouse gas than CO2, there is over 200 times more CO2 in the atmosphere.

Relevance (1 = gold evidence, 0 = mined hard negative): 1
Passage: Methane in the Earth's atmosphere is a strong greenhouse gas with a global warming potential (GWP) 104 times greater than CO2 in a 20-year time frame; methane is not as persistent a gas as CO2 (assuming no change in carbon sequestration rates) and tails off to about GWP of 28 for a 100-year time frame.

Relevance (1 = gold evidence, 0 = mined hard negative): 1
Passage: Methane is a strong GHG with a global warming potential 84 times greater than CO2 in a 20-year time frame.

Relevance (1 = gold evidence, 0 = mined hard negative): 1
Passage: That is, over a 20-year period, it traps 84 times more heat per mass unit than carbon dioxide (CO2) and 32 times the effect when accounting for aerosol interactions.

Relevance (1 = gold evidence, 0 = mined hard negative): 1
Passage: Since methane gas is twenty-five times stronger (for a given weight, averaged over 100 years) than CO 2 as a greenhouse gas; this would immensely magnify the greenhouse effect.

Relevance (1 = gold evidence, 0 = mined hard negative): 1
Passage: Natural gas is thus a more potent greenhouse gas than carbon dioxide due to the greater global-warming potential of methane.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: Methane is a significantly more potent greenhouse gas than carbon dioxide in the amount of heat it can trap, especially in the short term.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: Methane is an important greenhouse gas with a global warming potential of 34 compared to CO2 (potential of 1) over a 100-year period, and 72 over a 20-year period.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: There is concern over increases in atmospheric methane in the context of the global carbon cycle, because methane is a greenhouse gas that is 23 times more effective at absorbing long-wave radiation than CO on a 100-year time scale.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: The methane in biogas is 28 times more potent a greenhouse gas than carbon dioxide.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: On a 20-year timescale, a mass of methane is about 85 times more powerful than carbon dioxide at warming the Earth, but on a 100-year timescale, it is only about 28-34 times more powerful, because the carbon dioxide continues to warm the earth after the methane is gone.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: These emissions contribute to global climate change as methane is a potent greenhouse gas.

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: After water vapour (concentrations of which humans have limited capacity to influence) carbon dioxide is the most abundant and stable greenhouse gas in the atmosphere (methane rapidly reacts to form water vapour and carbon dioxide).

Relevance (1 = gold evidence, 0 = mined hard negative): 0
Passage: While the lifetime of atmospheric methane is relatively short when compared to carbon dioxide, with a half-life of about 7 years, it is more efficient at trapping heat in the atmosphere, so that a given quantity of methane has 84 times the global-warming potential of carbon dioxide over a 20-year period and 28 times over a 100-year period.