[titzer]

> Since the methane released from cattle is continually degrading, it does not accumulate.

That's like saying lakes are impossible because of rivers.

If you look at historical methane concentrations in our atmosphere, they are already almost 3x of pre-industrial levels, and over 3x of mean historical levels over the past ~1 million years [1]

[1] https://en.wikipedia.org/wiki/Atmospheric_methane

[agurk]

Interestingly only about 1/4 of today's emissions are directly caused by all agriculture according to NASA[0]. A decent chuck of modern emissions are caused by other human activities.

> Across the study years, wetlands contributed 30 percent of global methane emissions, with oil, gas, and coal activities accounting for 20 percent. Agriculture, including enteric fermentation and manure management, made up 24 percent of emissions, and landfills comprised 11 percent. Sixty-four percent of emissions came from tropical regions of South America, Asia, and Africa, with temperate regions accounting for 32 percent and the Arctic contributing 4 percent.

[0] https://earthobservatory.nasa.gov/images/146978/methane-emis...

[cwkoss]

I suspect that methane emission levels from energy industry are likely downplaying and underestimating total methane emissions from fracking and similar activities because they have a strong financial/political interest in doing so.

[pharke]

The wikipedia page you link to clearly shows that enteric fermentation accounts for 16% vs Coal and Oil at 19%. There is also another 36% anthropogenically produced methane in that chart so I think that easily accounts for the 3x increase without pinning it on cows. Interestingly rice cultivation contributes a whopping 12%.

[titzer]

It's like we got shot by a firing squad of 6 people and we're arguing about which one of them had the blank.

[pharke]

Not really, we're trying to do some important math to figure out how to balance a carbon budget. We need to know what options are on the table and how much each of them contribute. It's the same as balancing a household budget, you don't just flail wildly about slashing costs and enduring privation. You reduce expenditures in areas where they are unnecessary and try to cause the least disruption to your life.

[titzer]

I get what you are trying to say, but we don't have a carbon budget, nor a methane budget. Maybe attitudes need to shift gradually to make other people feel more comfortable, but the fact is that we need to make radical changes to all areas of human existence in order to deal properly with the magnitude of the crisis. It seems like...smart...to be rational, and weigh costs and impact and supposedly choose the smartest strategy and all, but it's mostly just a vehicle for one sector to shift the blame on another and try to make it someone else's problem. I know you specifically aren't doing that, but the end result is that nothing will ever get done, as we will be in analysis paralysis even as it all comes unraveled.

[Retric]

Natural CO2 sinks that absorb carbon from volcanos exist. As such we can have some net human CO2 production without making things worse than they are today.

An 80% reduction in CO2 isn’t quite enough, but it would avert most issues for a long time. More importantly doing something is much more productive than saying we need to change everything on day one which just promotes paralysis.

The obvious step one is to get cars and electricity to ~zero. That’s achievable in 20 years especially when you consider gas stations closing are going to make ICE engines unappealing.

[whitexn--g28h]

Gas stations are closing because ICE engines are getting more efficient and now have a lot more range. I think this is going to make them more appealing in the short term.

[pbhjpbhj]

FWIW, IPCC (International Panel on Climate Change) reports gather statistics and best practice across science and engineering and produce reports at multiple levels to detail pertinent statistics on this area.

This seems to be a good review, https://www.c2es.org/content/ipcc-fifth-assessment-report/.

The sixth report is due soon. Everyone should read the policymakers summary IMO.

[graeme]

Is that from cow herd size increases or other causes? OP’s point was that with q fixed herd size the amount of methane accumulating in an atmosphere is stable.

Lakes don’t grow and grow and consume the world.

[titzer]

> Lakes don’t grow and grow and consume the world.

No, they don't usually grow forever, that's true. But floods happen, and that's bad. Last time methane was this high it was millions of years ago, and Earth had no ice caps. We have already flooded the atmosphere with methane, and the consequences of this will take decades, if not centuries, to play out. Contrary to our current instant-gratification dopamine loops of today, the lag between cause and effect isn't two damn seconds or even one frickin year. So stay tuned.

Was it all from agriculture? We don't know. There's plenty of methane coming from fossil fuel production. Just go read the Wikipedia article I linked. We do know that we are getting close to setting off some very bad feedback loops, as arctic permafrost is starting to thaw, and it's going to produce gobs of methane.

[8note]

Floods tend to come from melt or tonnes of heavy rain.

That's much more akin to digging carbon out of the ground to run processes than steady state cow methane production/degradation

[zackees]

Going to chime in here - ice ages cause extinctions, not warm ages.

We are in the knifes edge of too cold. A little extra green house gas to buffer out the ice age is a good thing.

[howlin]

The problem is the millions to billions of people who are living in areas that will become virtually uninhabitable due to temperature changes and sea level rise. The first way climate change will seriously negatively impact humanity is through geopolitical conflict and a massive refugee crisis.

[zackees]

Yet that hasn’t happened despite all the warnings in the media for 3 decades of my life and no significant rise in sea level in my lifetime.

The alarmism is more likely propaganda than legitimate scientific inquiry.

[Gustomaximus]

What sea level rise would be significant to you?

Its happening and accelerating: https://climate.nasa.gov/vital-signs/sea-level/

If you need something visual look at the Miami type floods.

Also consider this is an issue that needs to be planned across hundreds of years. It might be slow but we dont move a city like NY in a decade.

Look at this: https://sealevelrise.org/states/new-york/#:~:text=The%20sea%....

Genuinely, do you feel these links are alarmism and propaganda?

[dTal]

Change causes extinctions. If the temperature suddenly swings down, things die. If it subsequently swings back up, do they come back? No! More things die.

[sampo]

Methane from human activities:

    Methane leaks from fossil fuel systems: 30%
    Methane from landfills: 20%
    Animal agriculture, including also manure management: 30%
    Plant agriculture: 15%
    Other: 5%

https://en.wikipedia.org/wiki/Methane_emissions

Plant agriculture is especially rice paddies, I guess.

[graeme]

If methane is only 3x larger than before, that suggests animal husbandry is only a small part of the increase.

The first two categories are almost entirely new. Especially given human population is way bigger than it was in past ages, so past landfills likely weren’t so large.

This is surprising to me as I has figured ruminants caused more of an increase. If we could cut their emissions by 80% with seaweed this analysis suggests their overall contribution would be lower than it historically was.