How Do Methane and Hydrogen Sulfide Contribute to Global Warming?

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Methane (CH4) is lighter than air, with a molecular mass of 16 amu compared to nitrogen (N2) and oxygen (O2), which have higher molecular masses. Its density is 0.657 kg/m³, while air's density is 1.225 kg/m³. Hydrogen sulfide (H2S) is slightly heavier than oxygen but still participates in atmospheric dynamics. The discussion clarifies that both gases can rise into the atmosphere due to convection and turbulence, which mix gases regardless of their densities. This mixing occurs at both large and small scales, meaning that they do not remain strictly in low-lying areas. The concept of "disintegration" is a misunderstanding; rather, the gases can diffuse and be carried aloft by warm air, making their presence formidable despite their initial densities. Understanding these dynamics is crucial, especially given the current environmental context.
moriah
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Atmospheric scientists are reporting that methane is the second most prevalent gas trapped in the ozone layer.
Methane and hydrogen sulfide are supposed to be heavier then air, thus why they remain in low lying areas. I am to believe that only when they begin to disintegrate, they rise into the atmosphere. So my question is, if these gases are already disintegrated, how can they be so formidable?
 
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moriah said:
Summary:: Atmospheric scientists are reporting that methane is the second most prevalent gas trapped in the ozone layer.

Methane
Methane (CH4) has a molecular mass of 12+4*1 = 16 amu. N2 has a molecular mass of 2*14 = 28 amu, and O2 has molecular mass of 2*16 = 32 amu. 16 < 28, 32, so methane is a lighter molecule than the two main constituents of air, and methane would be lighter barring any hydrogen bonding with other molecules. Also, density of methane = 0.657 kg/m³, while density of air is 1.225 kg/m³, consistent with the lighter CH4 molecule.

H2S, molecular mass 2*1 + 32 = 34 is slightly heavier than O2.

moriah said:
So my question is, if these gases are already disintegrated, how can they be so formidable?
If methane and hydrogen sulfide absorb more energy from sunlight than the air, then those molecules would diffuse into the air. If they exchange heat with the air, the warmer air rises while colder air somewhere sinks. Methane could be carried aloft with warm air, and if enough methane is present, light methane molecules displace air molecules, which makes that volume of air 'lighter', even without additional heating.
 
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moriah said:
Summary:: Atmospheric scientists are reporting that methane is the second most prevalent gas trapped in the ozone layer.

Methane and hydrogen sulfide are supposed to be heavier then air, thus why they remain in low lying areas. I am to believe that only when they begin to disintegrate, they rise into the atmosphere.
This sounds like a basic misunderstanding.

Convection driven bulk air movements and accompanying turbulence mixes these gases at large scales, irrespective of their relative densities. Volcanic H2S from large eruptions for example is carried high into the atmosphere because of convection.

Diffusion mixes them at small scales even in still air. They don't stratify in the atmosphere although higher concentrations are near sources. "Disintegration"?
 
Ken Fabian said:
This sounds like a basic misunderstanding.

Convection driven bulk air movements and accompanying turbulence mixes these gases at large scales, irrespective of their relative densities. Volcanic H2S from large eruptions for example is carried high into the atmosphere because of convection.

Diffusion mixes them at small scales even in still air. They don't stratify in the atmosphere although higher concentrations are near sources. "Disintegration"?
That answered my question very thoroughly. I was mistaken about the density of methane: it’s lighter than air. However in light of your response, density is rather irrelevant. Understanding this issue at your level of expertise is critical at this point in history.
 
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