This seaweed additive they propose is a distraction. Even if it would work, it's a band-aid at best. The real, more simple, cheaper and healthier solution is to make meat and dairy from plants directly.
What are you referring to when you say "usable land"? What means usable? Presumably you refer to agriculture and I'm not sure where your number comes from. 42 percent of the land acreage of Canada is covered by forests. This is the percentage forest cover by each State in the U.S. - https://en.wikipedia.org/wiki/Forest_cover_by_state_and_terr...
> In which other areas do you propose to increase trees and plants?
Anywhere else appropriate.
> This seaweed additive they propose is a distraction
It's a solution, given that among the problems framed is the level of methane emissions.
> Even if it would work, it's a band-aid at best.
There has been research papers illustrating the impact of seaweed in cattle feed for years now - it works.
No one is framing this as the entire solution to global warming. If it can curb methane to that extent, it has a substantial impact.
> The real, more simple, cheaper and healthier solution is to make meat and dairy from plants directly.
We already have "alternative" products on the market which aren't that popular, but no actual lab-grown meat on the market. The "real" solution (to this minor subset of a larger issue) is one that exists, or could viably be cost-effective enough to consumers tastes. I see no suggestion that lab-grown meat would be cheap, or healthier, or simpler.
I'm not talking about lab-grown meat, I'm talking about plant-based meat and dairy. The most important thing to do is to creat plant-based meat and dairy alternatives that are better than animal-based products. It's hard but it's possible already possible today (e.g. see Impossible Foods).
To the extent that the problem extends much further than level of consumption of cattle, that is true. But if widespread adoption of feed can effectively reduce methane emissions from cattle, as you said it targets one of the primary drivers - that's more than a start. This helps you visualize the impacts of various solutions, notice what happens when all other things held equal you drop methane - https://en-roads.climateinteractive.org/scenario.html?p1=45&...
> if we would let nature reclaim the land that's currently used for livestock agriculture, it has the potential to capture >100% of the CO2 emissions until 2050.
This is a moot point considering that trees and plant numbers could be increased in many other areas, particularly where they are felled in high numbers, and not all pasture land is appropriate for plant agriculture or otherwise.
There is a short-term battle and a long-term one. We do need to curb emissions in the short-term substantially, which will require innovation and policy changes. Long-term, the fact is land encroachment and destruction scales with the population; we all have an environmental footprint, and slightly increasing its efficiency will never outpace and counteract the impact of perpetual population increase. It's projected to curb more in the future as more of the global population gets lifted out of poverty, and access to contraceptives is more universal - however, this could be accelerated. There's no reason we can't quash global poverty further right now.