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