I'm tying to find any clue about the timescale of the biological pump. That the carbon is recycled to the surface ca. 1,000 years is clear but the timescale of the biological pump seems hard to find. There is an report I saw when I was surfing the internet saying that the timescale can range from 45 days to 5 years which I find is a little shocking. Does it truly vary that much, or there is something wrong about the data?