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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

#261

Post by WalterBright »

hinkley wrote: post #13

We just had a conversation the other day about climate change and methane, and some people were saying 20x as strong as CO2, and others were saying and sometimes correcting them to 28. According to this article the correct answer is 20. That’s still over an order of magnitude difference. It still doesn’t change the priorities much, it means you can leak 40% more methane from a system before it’s worse that coal, but…

Methane also has a half-life in the atmosphere of 12 years, rather than centuries for CO2.

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

#262

Post by himinlomax »

dataflow wrote: post #234
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…

> Methane naturally turns into CO2 in the atmosphere After how long? A half-life of a decade , as I understand it? Not exactly the order of magnitude of luxury time we have to spare. > Even if it did increase warming more than CO2 "Even if it did" is strange wording for an established fact. Do you write "even if the sky was blue"? > once methane emissions reach a steady level, reducing methane emissions won't change…

> After how long? A half-life of a decade, as I understand it? Not exactly the order of magnitude of luxury time we have to spare

Doesn't matter, if we keep the number of heads of cattle constant, the methane from them in the atmosphere will be constant.

If we keep using the same number of ICE cars otoh, the CO2 from them in the atmosphere will keep increasing. We would have to drop the number of ICE cars to 0 to stop the increase.

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

#263

Post by imtringued »

kvgr wrote: post #66
orev wrote: post #59

Earlier quoted context omitted.

Plants that feed the cattle are overwhelmingly fertilized using fertilizer derived from petroleum products, so it’s not an accurate picture that the feed plants are carbon capture methods.

All plants we eat are fertilized. We can stop fertilizing and all die.

That isn't true. The carrying capacity of the earth would shrink but there would be enough food for at least a billion people.

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

#264

Post by whythre »

phtrivier wrote: post #259
ftrobro wrote: post #252

Earlier quoted context omitted.

> I don't think your conclusion that this loop doesn't accelerate the greenhouse effect is correct It's not like mammalian herbivores are a recent invention. If a constant amount of mammalian herbivores in the world would cause a constant acceleration of greenhouse effect then the greenhouse effect would have increased exponentially for millions of years already. That has not been the case. If you increase the number…

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.

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

#265

Post by squeaky-clean »

ftrobro wrote: post #252
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…

> I don't think your conclusion that this loop doesn't accelerate the greenhouse effect is correct It's not like mammalian herbivores are a recent invention. If a constant amount of mammalian herbivores in the world would cause a constant acceleration of greenhouse effect then the greenhouse effect would have increased exponentially for millions of years already. That has not been the case. If you increase the number…

> It's not like mammalian herbivores are a recent invention. If a constant amount of mammalian herbivores in the world would cause a constant acceleration of greenhouse effect then the greenhouse effect would have increased exponentially for millions of years already.

Factory style livestock farming is a recent invention. There's no way a similar amount of herbivores existed a million years ago in the wild compared to what we can currently cage and feed corn product to.

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

#266

Post by squeaky-clean »

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.

There are roughly 1.5 billion cows in the world right now.

https://cairncrestfarm.com/blog/how-many-cows-are-there-in-t...

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

#267

Post by squeaky-clean »

kvgr wrote: post #66
orev wrote: post #59

Earlier quoted context omitted.

Plants that feed the cattle are overwhelmingly fertilized using fertilizer derived from petroleum products, so it’s not an accurate picture that the feed plants are carbon capture methods.

All plants we eat are fertilized. We can stop fertilizing and all die.

This is unrelated to the argument that animal feed from plants is/isn't a sustainable method of carbon capture.

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

#268

Post by varjag »

least wrote: post #190
eastof wrote: post #159

Earlier quoted context omitted.

> nutrients [...] only found in meat Nutritional yeast is tasty and naturally has b12, and most cereals/grains are fortified with it. > amino acids [...] only found in meat This just isn't true, you can get all amino acids from plant-based sources like soybeans, lentils, and peanuts. Source: I have been vegan for 5 years and I still have a healthy 6 minute mile, 25 consecutive pullups, V5-V7 range boulder problem cli…

> Nutritional yeast is tasty and naturally has b12, and most cereals/grains are fortified with it. Taurine, Carnosine, Creatine, and B12 don't exist in significant quantities outside of meat. Nutritional yeast is often supplemented with B12 but the bioavailability of it compared to animal protein is low. You will need to take an actual supplement to get the right amount of B12 your body needs to function optimally. Y…

B12 absolutely exists in many species of fish, it larger concentrations than in meat.

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

#269

Post by chalst »

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…

> 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.

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

#270

Post by tuatoru »

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…

> That shockingly simplistic models and the barest of data don't actually have predictive power wouldn't surprise people in any other scientific discipline

This is dead wrong. It's a source of wonder in most scientific disciplines that heavily simplified models can have amazingly good predictive power.

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