Methane as a greenhouse gas

[Philolsophy]

I was looking into the matter of methane as a greenhouse gas. Just as with CO2, it is rising sharply. From what I was reading, they say that methane is 84 to 87 times more potent of a greenhouse gas than CO2. That being over a 20 year timeframe. But methane only last in the atmosphere as methane for about 10 years. So would I be wrong in assuming that during the 10 years where methane is released at any particular point into the atmosphere, it is well over 100 times more potent of a greenhouse gas than CO2?

This is an important question. Because any time I see anything on TV about human caused global warming, they talk about what ocean levels will be like in the year 2100. But by the looks of things, most of the life on Earth will be extinct by the year 2050. Mainly because of the exponentially increasing amount of methane release. Also, I have a picture to show you of what the Earth looked like in 1972 and what it looked like from the recent Artemis moon flyby over 50 years later. As you can see, the Earth looks noticeably dingier. Which in itself must mean that the atmosphere is absorbing more heat from the sun.

 

[berkeman]

Please always post links to your claims and to your images. We need those links to be sure that PF stays compliant with copyright regulations, and to help other PF users to be able to respond to your post.

 

[Baluncore]

From what I was reading, they say that methane is 84 to 87 times more potent of a greenhouse gas than CO2. That being over a 20 year timeframe. But methane only last in the atmosphere as methane for about 10 years. So would I be wrong in assuming that during the 10 years where methane is released at any particular point into the atmosphere, it is well over 100 times more potent of a greenhouse gas than CO2?

That would be a false assumption. Once CO2 is added to the atmosphere, it hangs around, for a long time: between 300 to 1,000 years.

 

[renormalize]

Also, I have a picture to show you of what the Earth looked like in 1972 and what it looked like from the recent Artemis moon flyby over 50 years later. As you can see, the Earth looks noticeably dingier. Which in itself must mean that the atmosphere is absorbing more heat from the sun.

I boosted the brightness and contrast a bit on your Artemis photo and voilà! Earth in 2026 actually looks as good or even better than it did in 1972!

My point is simply that you cannot draw scientifically valid conclusions without referencing your data to properly calibrated standards.

 

[berkeman]

I boosted the brightness and contrast a bit on your Artemis photo and voilà! Earth in 2026 actually looks as good or even better than it did in 1972!

Except North America has morphed into Australia! Plate tectonics?

 

[renormalize]

Except North America has morphed into Australia! Plate tectonics?

Must be a Rorschach test! I see Africa, the Middle East and Madagascar in 1972 and Australia(?) in 2026.

 

[Hornbein]

Except North America has morphed into Australia! Plate tectonics?

The Great Morph has been covered up. If they knew the people might panic.

 

[Ken Fabian]

Surely average residence time is not the same as how long before it has all decayed to CH4 and H2O from contact with OH radicals - some will decompose sooner than the average and some will decompose later. Because some will still be present in the atmosphere after the average time has passed it does not look like a mistake or inconsistent to consider the effects over longer periods than average residence time.

 

[Bandersnatch]

But by the looks of things, most of the life on Earth will be extinct by the year 2050.

There's no reason to think that. Certainly none given in the opening post.
If you've just found out about methane's role in global warming - that's excellent. But it's not news to climate modelling, and the predictions for the range of temperature increase that percolate to the general discussion space do include methane emissions, together with a multitude of other factors.

 

[pinball1970]

I was looking into the matter of methane as a greenhouse gas. Just as with CO2, it is rising sharply. From what I was reading, they say that methane is 84 to 87 times more potent of a greenhouse gas than CO2. That being over a 20 year timeframe. But methane only last in the atmosphere as methane for about 10 years. So would I be wrong in assuming that during the 10 years where methane is released at any particular point into the atmosphere, it is well over 100 times more potent of a greenhouse gas than CO2?

This may be useful to you.

https://www.epa.gov/ghgemissions/understanding-global-warming-potentials

 

[DaveC426913]

As you can see, the Earth looks noticeably dingier. Which in itself must mean that the atmosphere is absorbing more heat from the sun.

Noooo.

The 1972 pic was taken of the sunward side of the Earth - almost full sun.

The 2026 pic was taken of the Earth's night side - it has been artificially brightened for your viewing pleasure. Notice the full brunt of the sun on the lower right limb - proving that we are definitely looking at the night side.

Here it is before enhancement:

(and if you look closely enough at the lower left limb, you can see city lights along the African coast.)