All of the (as you say, inadequate) climate accord plans already assume that we are going to develop magical carbon-sequestration technology and deploy it on a global scale by 2050 or so.[0]

So basically, it's even worse than you might think. Not only do we have to cut our emissions dramatically, but we also have to invent some technology for negative emissions.

[0] https://www.vox.com/2016/10/4/13118594/2-degrees-no-more-fos...