10bn tonnes must be captured from the air every year to limit global heating to 1.7C, says Johan Rockström
Problem is this part:
To achieve this through technological means, such as direct air capture, would require the construction of the world’s second biggest industry, after oil and gas, and require expenditures of about a trillion dollars a year, scientists said. It would need to be done alongside much more drastic emissions cuts and could also have unintended consequences.
That makes it incredibly unlikely that this kind of removal will be done.
Even if we set our global net emissions to 0 right now it’s not gonna get colder again in our lives or the lives of the next 100 generations. The carbon was in the ground, we burnt it, now it’s in the atmosphere as co2. To get it back down, we need negative net emissions aka co2 recapture.
And needless to say, getting our global net emissions anywhere close to 0 isn’t even really in reach for the next 50 years, so if we can do recapture alongside reducing emissions that would probably be great. Particularly in the wealthy western nations that might reach at least nominal net 0 at some point in this century.