https://www.sciencedaily.com/releases/2015/03/150319143337.htm
Geoengineering proposal may backfire: Ocean pipes 'not cool,' would end up warming climateDate:March 19, 2015Source:Carnegie InstitutionSummary:There are a variety of proposals that involve using vertical ocean pipes to move seawater to the surface from the depths in order to reap different potential climate benefits. One idea involves using ocean pipes to facilitate direct physical cooling of the surface ocean by replacing warm surface ocean waters with colder, deeper waters. New research shows that these pipes could actually increase global warming quite drastically On 12 Sep 2017 00:21, "Robert Tulip" <[email protected]> wrote: > Dear Andrew > Thank you very much for bringing this potential problem with Deep Ocean > Water as an algae nutrient source to attention. I would like to find out > more about the possible mechanism that you allude to. I looked again at > the 2005 IPCC paper on Ocean Storage <https://www.ipcc.ch/report/srccs/> led > by Professor Caldeira but did not find anything to support your reference. > If more recent work shows that raising DOW could cause warming I would like > to see it. I am following up other responses to my comments directly with > their authors. > Robert Tulip > > > ------------------------------ > *From:* Andrew Lockley <[email protected]> > *To:* Robert Tulip <[email protected]>; geoengineering < > [email protected]> > *Sent:* Friday, 8 September 2017, 10:47 > *Subject:* Re: [geo] Carbon budget/removal in NYTimes interactive > > Caldeira et al showed that moving water in this way causes warming. > > A > > On 8 Sep 2017 00:15, "'Robert Tulip' via geoengineering" < > [email protected]> wrote: > > Thanks Cristoph. > Deep Ocean Water, with volume about a billion cubic kilometres below the > thermocline, has about three ppm nitrate and phosphate, about 3000 cubic > kilometres of each, as I understand the numbers. Tidal pumping arrays along > the world's continental shelves could raise enough DOW to the surface, > mimicking natural algae blooms, to fuel controlled algae production at the > scale required for seven million square kilometres of factories. Piping > CO2 from power plants etc out to ocean algae farms could clean up all the > polluted air of the world. > Robert Tulip > > > ------------------------------ > *From:* Christoph Voelker <[email protected]> > *To:* geoengineering@googlegroups. com <[email protected]> > *Sent:* Friday, 8 September 2017, 8:43 > *Subject:* Re: [geo] Carbon budget/removal in NYTimes interactive > > I must admit that I am getting skeptical when I hear numbers in that order > of magnitude: > The total net primary production in the oceans presently is about 50 Gt > carbon, and 80% of that is converted back into inorganic carbon (and > nutrients) by heterotrophs before it gets a chance to sink out from the > sunlit upper layer of the ocean. The roughly 10 Gt carbon (some newer works > even estimate just 6 Gt carbon) that sink out have to be balanced by the > upward mixing of nutrients (and a little bit by atmospheric deposition of > bioavailable nitrogen and phosphorus) in the Redfield ratio of about > 106:16:1 of C:N:P. > So, if you want to remove 20 Gt carbon per year from the atmosphere, you'd > have to increase the nutrient supply to the total surface ocean by a factor > of three, maybe four. Maybe I am a bit too pessimistic here, because there > are species like Sargassum which have a higher C:N:P ratio than the average > phytoplankton, so you get somewhat more carbon per nitrogen/phosphorus. But > even if it is just doubling, I can't imagine that you can sustain such a > nutrient consumption by fertilizing from outside the ocean (especially > since phosphorus is scarce already now), you'd have to tap into the > inorganic nutrients stored in the deep ocean. How long can you do that? > If we assume that we harvest all the 20 Gt carbon in algae from these > factories and do something durable with them (to minimize lossed through > heterotrophy and problems with creating oxygen minimum zones), we > effectively remove nitrogen/phosphorus from the ocean. How much is that per > year? > Let us for simplicity assume Redfield ratios, I grant errors by a factor > of two or so. 20 Gt carbon then corresponds to (20 > g/12(g/mol)/6.625(molC/molN))* 1.0e15 or about 2.5e14 mol nitrogen. The > ocean has a volume of 1.33e18 m^3, and the average concentration of > available nitrogen (mostly nitrate) is 30 micromol/L or mmol/m^3 > (calculated from the world ocean atlas), most of that is in the deep ocean. > This gives a total inventory of 4.0e16 mol nitrogen. 2.5e14 mol/year is > thus more than half of a percent of the total available nitrogen in the > world oceans, which means you could try that for about 150 years, then > everything is gone At that pace, nitrogen fixers are unlikely to resupply > the loss (nowaday, the residence time of nitrogen is roughly 5000 years), > and they can do that only for nitrogen, not for phosphorus anyway. Letting > technological problems aside (like: How do you move 2.5% of the total > nitrogen in the world oceans evry year up to an area 2% of the ocean > surface) I would call the whole idea - at least that the scale suggested - > a prime example of an unsustainable process. > Best regards, > Christoph Voelker > > On 07.09.17 23:37, 'Robert Tulip' via geoengineering wrote: > > The assumption behind the NYT interactive model > <https://www.nytimes.com/interactive/2017/08/29/opinion/climate-change-carbon-budget.html?action=click&pgtype=Homepage&clickSource=story-heading&module=opinion-c-col-right-region®ion=opinion-c-col-right-region&WT.nav=opinion-c-col-right-region> > that the upper bound for carbon removal is 12 GT CO2 by 2080 is too slow > and small. We should think five times as much and five times as fast. > Immediate aggressive investment to build industrial algae factories at sea > could remove twenty gigatons of carbon (50 GT CO2) from the air per year by > 2030, using 2% of the ocean surface, funded by use of the produced algae. > That would stabilise the climate and enable no change in emission > trajectories, a policy result that would satisfy both the needs of the > climate and the traditional economy. > Robert Tulip > > > ------------------------------ > *From:* Eric Durbrow <[email protected]> <[email protected]> > *To:* geoengineering <geoengineering@googlegroups. com> > <[email protected]> > *Sent:* Thursday, 7 September 2017, 3:13 > *Subject:* [geo] Carbon budget/removal in NYTimes interactive > > > FYI There is a slick interactive graphic at the NYTimes that lets people > see if they can meet the world’s carbon budget restriction but a > combination of reduced emissions AND achieving Carbon Removal. > > At > > https://www.nytimes.com/ interactive/2017/08/29/ > opinion/climate-change-carbon- budget.html?action=click& > pgtype=Homepage&clickSource= story-heading&module=opinion- > c-col-right-region®ion= opinion-c-col-right-region&WT. > nav=opinion-c-col-right-region > <https://www.nytimes.com/interactive/2017/08/29/opinion/climate-change-carbon-budget.html?action=click&pgtype=Homepage&clickSource=story-heading&module=opinion-c-col-right-region®ion=opinion-c-col-right-region&WT.nav=opinion-c-col-right-region> > > I failed after clicking on Reduce in all geographic areas and Achieve in > Carbon Removal. > > > > > -- > You received this message because you are subscribed to the Google Groups > "geoengineering" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to geoengineering+unsubscribe@ googlegroups.com > <[email protected]>. > To post to this group, send email to geoengineering@googlegroups. com > <[email protected]>. > Visit this group at https://groups.google.com/ group/geoengineering > <https://groups.google.com/group/geoengineering>. > For more options, visit https://groups.google.com/d/ optout > <https://groups.google.com/d/optout>. > > > -- > You received this message because you are subscribed to the Google Groups > "geoengineering" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to geoengineering+unsubscribe@ googlegroups.com > <[email protected]>. > To post to this group, send email to geoengineering@googlegroups. com > <[email protected]>. > Visit this group at https://groups.google.com/ group/geoengineering > <https://groups.google.com/group/geoengineering>. > For more options, visit https://groups.google.com/d/ optout > <https://groups.google.com/d/optout>. > > -- > Christoph Voelker > Alfred Wegener Institute for Polar and Marine Research > Am Handelshafen 12 > 27570 Bremerhaven, Germany > e: [email protected] > t: +49 471 4831 1848 > > -- > You received this message because you are subscribed to the Google Groups > "geoengineering" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to geoengineering+unsubscribe@ googlegroups.com > <[email protected]>. > To post to this group, send email to geoengineering@googlegroups. com > <[email protected]>. > Visit this group at https://groups.google.com/ group/geoengineering > <https://groups.google.com/group/geoengineering>. > For more options, visit https://groups.google.com/d/ optout > <https://groups.google.com/d/optout>. > > > -- > You received this message because you are subscribed to the Google Groups > "geoengineering" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to geoengineering+unsubscribe@ googlegroups.com > <[email protected]>. > To post to this group, send email to geoengineering@googlegroups. com > <[email protected]>. > Visit this group at https://groups.google.com/ group/geoengineering > <https://groups.google.com/group/geoengineering>. > For more options, visit https://groups.google.com/d/ optout > <https://groups.google.com/d/optout>. > > > > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. 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