I have no proper knowledge about natural carbon sinks, their capacity and remaining capabilities. But from the amateur point of view I think there are 3 main po

I have no proper knowledge about natural carbon sinks, their capacity and remaining capabilities. But from the amateur point of view I think there are 3 main possibilities - vegetation, ocean and permafrost. Permafrost won't help because first the planet need to cool down a lot and start general cooling trend. And we will be heating up the atmosphere due to existing gasses. So it's a dead end. Vegetation is a linear carbon sink. Because microbes decompose dead vegetation and release gasses back in the atmosphere, the most of the captured carbon in vegetation must be in the actual alive plants. And number of alive plants scales linearly with the area we humans leave for them. Since humanity is increasing in numbers and each human demands more and more land to be used, I highly doubt that we can spare a lot of arable land for a NEW vegetation. So that's also dead end. And at last oceans. I have no idea what is the capture mechanism of an ocean and how much carbon on it's own it can capture permanently. Maybe yes, maybe no. But considering that a) we are acidifying oceans, b) overfishing them, c) raise sea levels, d) heat up oceans - all this together would probably hamper natural carbon capture capabilities of an ocean. So maybe this is possible. But I haven't heard a lot about such possibility from scientists, and I doubt it's a solution for our problem. Until some research will be done at least.