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Methane may not warm the Earth quite as much as previously thought

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Re: Methane may not warm the Earth quite as much as previously thought

#271

Post by bobthepanda »

ramblenode wrote: post #236
machina_ex_deus wrote: post #50

Earlier quoted context omitted.

Methane naturally turns into CO2 in the atmosphere. Even if it did increase warming more than CO2, once methane emissions reach a steady level, reducing methane emissions won't change a thing, compared to CO2 emissions. This is also similar to meat production emissions. Most of carbon emissions in meat productions are of carbon which was captured from the air as a part of the production cycle, by the plants which fee…

You make a good point about animal-based carbon emissions being a closed loop, but I don't think your conclusion that this loop doesn't accelerate the greenhouse effect is correct. Methane degrades to C02 in 1-1 proportion. So at any time, if more atmospheric carbon is concentrated as methane than as C02 then the greenhouse effect will be stronger at that time (because methane is a stronger GHG). If agriculture remov…

Eh, we use plenty of petroleum based fertilizer to grow animal feed, so it is still there.

Re: Methane may not warm the Earth quite as much as previously thought

#272

Post by [deleted] »

shrubble wrote: post #40

This is exactly what the "deniers" have been saying - that the mathematical model is not fleshed out enough, and the data is not present in sufficiently accurate quantity, for the climate models to be accurate. This research shows that the mechanism of action was misunderstood all this time. What else hasn't been researched enough and has simplistic assumptions baked into the climate models? That shockingly simplisti…

[deleted]

Re: Methane may not warm the Earth quite as much as previously thought

#273

Post by CameronNemo »

whythre wrote: post #264
phtrivier wrote: post #259

Earlier quoted context omitted.

It's not new, but the number has hardly stayed constant, since at some point humanity started mass herding. And, also, we kinda quadrupled the cheptel size in 50 years ? https://ourworldindata.org/meat-production#global-meat-produ... (To be fair, I was expecting more, and I was again astonished by the relative numbers of cattle vs poultry)

We have increased farming, but the American plains were there once home to vast herds of bison. Basically there’s been 30 million large ungulates there for a very long time.

Yeah... And we hunted that population to... ?

Humans and their livestock make up the vast majority of the mamallian biomass.

Re: Methane may not warm the Earth quite as much as previously thought

#274

Post by mattashii »

chalst wrote: post #269
ramblenode wrote: post #236

Earlier quoted context omitted.

You make a good point about animal-based carbon emissions being a closed loop, but I don't think your conclusion that this loop doesn't accelerate the greenhouse effect is correct. Methane degrades to C02 in 1-1 proportion. So at any time, if more atmospheric carbon is concentrated as methane than as C02 then the greenhouse effect will be stronger at that time (because methane is a stronger GHG). If agriculture remov…

> Methane degrades to C02 in 1-1 proportion Source? I understood that the long-term radiative forcing of methane was lower than CO2, which is incompatible with this claim.

Presumably, each molecule of atmospheric methane (CH4) primarily degrades through oxidation to 1 CO2 and 2x H2O - this is basic chemestry.

Although atmospheric losses to space and capture into oceans and subsequent precipitation into hydrates cannot be excluded as potential atmospheric methane sinks, I expect those to be only marginal at the grand scheme of things.

Re: Methane may not warm the Earth quite as much as previously thought

#275

Post by adammarples »

chalst wrote: post #269
ramblenode wrote: post #236

Earlier quoted context omitted.

You make a good point about animal-based carbon emissions being a closed loop, but I don't think your conclusion that this loop doesn't accelerate the greenhouse effect is correct. Methane degrades to C02 in 1-1 proportion. So at any time, if more atmospheric carbon is concentrated as methane than as C02 then the greenhouse effect will be stronger at that time (because methane is a stronger GHG). If agriculture remov…

> Methane degrades to C02 in 1-1 proportion Source? I understood that the long-term radiative forcing of methane was lower than CO2, which is incompatible with this claim.

The source there would be that they both contain only one carbon atom...

Re: Methane may not warm the Earth quite as much as previously thought

#276

Post by xenonite »

drKarl wrote: post #256

And the cows taking all the blame for their flatulence

All the while cows' methane emissions can be greatly reduced, e.g., by oxidizing methane or by using food supplements that reduce enteric fermentation.

One should not forget soil erosion of typical farming, with a big environmental impact. This can be alleviated by letting cows graze on land to stock carbon in the soil (sequestration of soil organic carbon).

Re: Methane may not warm the Earth quite as much as previously thought

#277

Post by myshpa »

revelio wrote: post #255
myshpa wrote: post #205

Earlier quoted context omitted.

It seems that AVHRR was launched in 1978 [0], with fairly continuous global coverage since June 1979 [1]. So it was not in early 1970s, it was in the late 1970s, and it was not in early 1980s. You both were pretty close. > Polar bears are doing fine, by the way. Good to hear. For now at least. If true. "In 2004, biologists discovered four drowned polar bears in the Beaufort Sea. Never before observed, biologists attr…

From your wiki link: "AVHRR data have been collected continuously since 1981" ChatGPT was off by a decade! I hope nobody will confuse an anecdote about a handful of bears from 2004 with robust science.

Robust science? You mean NY Times or Chicago Tribune?

Re: Methane may not warm the Earth quite as much as previously thought

#278

Post by adammarples »

fooker wrote: post #233
jarenmf wrote: post #122

Earlier quoted context omitted.

> if a scientist questions climate science, he becomes a pariah As a climate scientist myself, I can tell you this is untrue and a harmful legend. As climate science is mostly atmospheric physics, biology and chemistry, it's pretty much very easy to disagree with anyone if you have a good argument supported by data. If you have strong scientific arguments, it does not matter even if the whole world is against you. On…

> If you have strong scientific arguments, it does not matter even if the whole world is against you. That’s a nice idealistic thing to say. Academia has shown this to be false again and again. Most groundbreaking ideas or arguments which go against the current wisdom get buried in the best case, and the proponents scorned and driven out of research in the worst case. It has been like this since the beginning of orga…

According to your logic then, science should not have been able to advance at all from the very beginning

Re: Methane may not warm the Earth quite as much as previously thought

#279

Post by tpnCC »

xyzzyz wrote: post #70
djleni wrote: post #56

Earlier quoted context omitted.

Could you explain further? How does: > reducing methane emissions won't change a thing, compared to CO2 emissions. Follow from: > once methane emissions reach a steady level

Methane in atmosphere today is at 2 ppm, carbon dioxide is at 420 ppm. If methane is 20 times more potent, this implies that atmospheric methane is equivalent to 40 extra ppm of carbon dioxide. If we removed literally all methane from the atmosphere, this would be equivalent to reducing carbon dioxide concentration to 380 ppm. This would bring us back to climate of 2005. By any reasonable measure, climate in 2023 is…

There is a detail missing in your Calculation.

Global Warming Potential of Methane over a 20 year Time period is a bit more than 80 times that of CO2. https://www.epa.gov/ghgemissions/understanding-global-warmin...

So, redrawing your path by your method, if we remove ALL of the Atmospheric Methane today, we would be reducing GHG concentrations by about 160ppm CO2 equivalent, which takes the overall CO2 concentrations to less than that of pre-industrial levels(280ppm), 260ppm.

This negates your conclusion that we would hardly observe ANY difference.

If we remove literally all of the Methane today, we would have solved Global warming from the perspective of concentration of Green House gases and will just have to wait and watch for the Global Temperatures to catch up (meaning they will go down).

Re: Methane may not warm the Earth quite as much as previously thought

#280

Post by adammarples »

revelio wrote: post #258
dmbche wrote: post #214

Earlier quoted context omitted.

(not a climate scientist) Also, for the graph showing "peaks" - it seems to me that the "pattern of peaks" is constant through your graph, but the average temperature rises continually through the peaks. If I were to guess, the peaks are things like volcanoes, currents and such, which are "constant" through time. The rise in CO2 is shown in the graph by the median not being a flat line.

If you have a step function and draw a trend line through it, the trend line will go up, but that doesn't imply a continuous process. CO2 forcing is (asserted to be) a continuous process. More co2 = higher temperature. The attempts to explain why that's observably not the case have become particularly wild in recent years, yet we are constantly told the science is settled and other untrue things.

Co2 is far from the only thing affecting temperature. The graph you're posting is clearly not a step function either. More like some kind of oscillation with an additional linear trend. Maybe the oscillation is el nino, it seems to be roughly periodic to 7 years or so, I don't know.

Edit: the bigger peaks are bang on el nino years, especially the '98 peak

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