Bill,
I don’t see how your scheme can work, in particular, “using bulk flow to sink the entire organic carbon soup of the wind-mixed layer (organisms plus the hundred-fold larger amounts of dissolved organic carbon) before its carbon reverts to CO2 and equilibrates with the atmosphere”. I don’t see how you can possibly sink by bulk flow more than a very small fraction of the surface mixed layer (and the associated algae, DOC etc) without an unbelievably dense array of devices with intakes at various depths in the mixed layer. Some other points: 1. Algal blooms generated by fertilization are not continuous but extend over a period of time. They take some time to get started - some 2-5 days in the case of ocean iron fertilisation blooms– and then take a further period of time to build up to a peak – up to 14 days or so in the case of ocean iron fertilisation blooms. Then they collapse! i.e. you cannot continuously pump nutrients up and algae etc down at the same time. 2. Throughout those periods of time, the blooms and the associated water masses will be being dispersed in the mixed layer. Thus, keeping the devices associated with the blooms is likely to be challenging especially since you aim to tether the devices to the seabed! 3. The assumption of 50g algae (dry weight) grown each day under each square meter of sunlit surface seems very high. Assuming a bit less than half of that is carbon, say 22g, then that is some 10-20 times more than the primary productivity of blooms measured in iron fertilization experiments. 4. I don’t understand the statement “Even if no fertilization results from pulling up, the DIC pulled up may be only half of the ~1g/m3 DOC pushed down” as the DIC:DOC ratio in oceanic waters is around 50:1. 5. Given the periods of time mentioned in 1 above, is it likely that little of the pulled up DIC will be released? Chris Vivian. On Friday, 18 January 2013 13:43:02 UTC, William H. Calvin wrote: > > Ken >> >> Sorry to miss your talk Monday in Seattle; I’m out of town for a while. >> >> I agree with you on the upwelling-only problems—and indeed I have agreed >> since about 2005 when you gave a nice talk at the ocean acidification >> workshop in Seattle. My cautions about up-only fertilization are in both my >> 2008 and 2012 books. So here I am talking *only* of push-pull ocean >> pumping. (We physiologists tend to be surrounded by push-pull pumps in the >> lab, which is likely why I began exploring pushing down at the same time as >> pulling up.) >> >> Upwelling and downwelling in combination is a different animal than >> up-only. For example, increasing surface ocean (and thus atmospheric) CO2 >> by pumping deep water up is a problem that goes away with the addition of >> simultaneously pushing surface water down. Even if no fertilization results >> from pulling up, the DIC pulled up may be only half of the ~1g/m3 DOC >> pushed down. With fertilization, one is pumping down both additional >> organisms and much more DOC. It’s important to sink this carbon soup before >> it has a chance to become surface DIC. >> >> My illustrative push-pull scheme is, of course, only an idealized sketch. >> It will take a Second Manhattan Project of real experts (such as yourself) >> to get it right. But my sketch does, I think, show that there is class of >> potential solutions that are possibly big enough (600 GtC), fast enough (20 >> yr), and secure enough against backsliding (for a millennium) to quality as >> a climate repair. >> >> Unlike anything else on the table, something like this looks capable of >> actually reversing the overheating, the acidification, and the thermal >> expansion portion of sea level rise. It would seem worth exploring. >> > -Bill wca...@uw.edu <javascript:> > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To view this discussion on the web visit https://groups.google.com/d/msg/geoengineering/-/KJHYR3cQO5AJ. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
