That's not right. The highest number I've been able to find for the whole of agriculture is 24% of world greenhouse gas emissions.
https://www.epa.gov/ghgemissions/global-greenhouse-gas-emiss...
About 25% of that is methane from livestock (http://old.grida.no/graphicslib/detail/greenhouse-gas-emissi...)
So livestock is about 6% of total greenhouse gas emissions.
So, even if methane takes a big share in current greenhouse emissions, its share in the accumulated greenhouse gases in the atmosphere will be lower.
The climate change it causes is temporary. (Disregarding runaway effects.)
Also, it decays into CO2, so to claim that its effects are temporary is misleading. On top of that, as long as the carbon is in a CH4 bond, it traps at least 20× as much radiation. Please don't dismiss the significance of methane emissions.
Honestly dude, rise above the cynicism (if that's how you meant to come across). You're a goddamn adult, and a well-educated engineer at that. Your current standard of living is at risk because of climate change (also millions of lives in poorer countries, but whatever). Spend 10 seconds on a Google search. "Activists" don't owe you any answers.
Never forget, despite what the sensationalists will tell you, climate change is very much fixable. Clean energy and better land management can and will get us there – and eventually, maybe in 200 years, we'll sequester enough carbon to get back to 350ppm. The question is about what happens in the meantime: if we act fast, we'll only get decades of food insecurity, war, and displacement, mostly in poorer countries [2]. If we delay further, we'll simply see much worse, and at home as well. But the "point of no return" rhetoric is nonsense and does nothing but paralyze people.
By the way, one of the easiest and fastest ways to catalyze at-scale solutions would be a revenue-neutral carbon tax at the source, effectively internalizing the social costs of climate change and letting the free market do its thing. (Look up "fee and dividend"; lots of folks are working on this already.)
[1] unless we hit some really unlucky runaway feedback loop, which is possible. [2] plus the disease epidemics and terrorism that come along with it – we don't live on an island.
I'm fully on-board with planetary engineering projects. Those require engineering work and capital more than activism, though.
Do you want to make a prediction on the accuracy of whatever climate model you like (we can use the one you linked if you prefer) for what the temperature increase will be in 2 years, 7 years, and 12 years? We can record it at https://predictionbook.com/
The political 2 degree goal is damage control. Climate models are complex and impacts harder to predict the more you divert from the current situation.
At 2 degrees the costs to society (social costs of carbon) far outweigh the mitigation costs. To hit the 2 degree target we have to act swiftly "we don't have decades to fix this" we are not (yet) at a "point of no return"
As green house gases are currently an externality, there will be no capital without activism.
I am too young to look back decades, but my understanding was that the "we don't have decades to fix this" guys in the 80s and 90s were more about running out of oil(and that turned out to be no problem as rising prices make more expensive extraction feasible) and that climate change as a concern only really started in the 90s (even though known long before that). And there are already damages that could have been prevented by acting swiftly in the 90s. We could have reached e.g. a 1.5 degree target. So the "we don't have decades to fix this" rethoric is fitting as ever.
If that carbon was already in the biosphere that’s mostly, fine long term. I worry a lot more about the carbon we keep adding to it, that wasn’t in the equation.
When you see the gas flares in hydrocarbon production fields it may look like a waste (it is), but it has to be done because the alternative of releasing methane into the atmosphere is worse.
Wikipedia puts (with some question about the citation) methan at 4-9% of total greenhouse effect contribution, and CO2 at 9-26%. (And then water vapor way above that, at 36-72%.) https://en.wikipedia.org/wiki/Greenhouse_gas#Greenhouse_gase...
https://newint.org/blog/2016/02/10/cowspiracy-stampeding-in-...
Short of an apocalyptic event, you could spend 100% of your spare time and energy trying to get people to stop eating meat and you'd be lucky to get a dozen lasting conversions. It's simply not an effective use of resources to make that your main/only focus.
How is it possible to product carbon capture, if all the grass is being consumed by cattle who then either exhale it or get eaten by humans who exhale it?
Animal Charity Evaluators found that for every $11 spent in online ads, you could make one person go to a website, sign up with their email, and pledge to go vegetarian for a year. The average vegetarian [1] produces 1.5 metric tons less CO2eq per year, so this means that the online ads decrease carbon at a cost of $7.40 per ton. That's cheaper than buying typical carbon offset certificates ($10-$15 per ton).
Maybe it's too optimistic to assume that everyone who makes a pledge on the website actually stays vegetarian for a year, or that they were average-level meat consumers before. Still, animal farming is bad enough that reducing it is probably cost-competitive with other current CO2 reduction approaches.
[1] I'm not sure if their use of "vegetarian" means "completely vegan".
It's the online equivalent to honking your horn for the protesters holding up signs next to the road. Easily done; easily forgotten.
Wouldn't you need to look at the difference in CO2eq between an average non-vegetarian and vegetarian?
Yes. According to the numbers of Food and Agriculture Organization of the United Nations, this would be about a 6.4% reduction in total green house gas emissions. See below for the numbers
> Total emissions from global livestock: 7.1 Gigatonnes of Co2-equiv per year, representing __14.5 percent of all anthropogenic GHG emissions__. This figure is in line FAO’s previous assessment, Livestock’s Long Shadow, published in 2006, although it is based on a much more detailed analysis and improved data sets. The two figures cannot be accurately compared, as reference periods and sources differ.
> About __44 percent of livestock emissions are in the form of methane__ (CH4). The remaining part is almost equally shared between Nitrous Dioxide (N2O, 29 percent) and Carbon Dioxide (CO2, 27 percent).
http://www.fao.org/news/story/en/item/197623/icode/
Food and Agriculture Organization of the United Nations
My understanding is that around half of the world's greenhouse gas comes from livestock. Would it mean that this could cut our emissions by half? Would it be therefore much more cost efficient to have the government invest is growing and distributing red algae than whatever we're currently spending money on? Do we have a sense of how much it would cost to produce that much seaweed?