Thank you Stephen. As I recall the version of OTEC that Jim Baird and Greg Rau addressed in their paper (cited in the cooling document I posted) harvests and circulates (with a low boiling point working fluid) heat rather than water. The ocean surface heat that is not harvested to produce energy (replacing existing energy production - per Jim's post) is released below the Ocean surface where it is estimated to take more than a couple of centuries to come back up to the surface again. At scale this is estimated to produce significant long-term global cooling somewhat analogous to the late 90's early 2000's hiatus global warming that resulted from temporary ocean currents that caused warm water down welling and cool water up welling during that period (as I recall). Ron Baiman
On Tue, Feb 21, 2023 at 7:43 AM Stephen Salter <[email protected]> wrote: > Hi All > > If you pump cold water up it will initially sink very quickly and then > spread out at the depth where the temperature is the same. > > If you pump warm surface water down it will initially rise quickly and > spread out when it gets to the depth still well below the surface with the > same density. > > One advantage of down pumping it that there is a slight positive pressure > inside the down tube which mean that it can be made with very cheap 250 > micron polythene in gentle tension. > > Small scale 1/100 scale models have been tank tested and filmed by > Discovery Channel. A key finding is that the fraction of the wave energy > that gets through the front wall travels across to the back wall and gets a > second gulp of water by sucking it in. I have designs for making very > large floppy structures. > > A paper written for hurricane moderation is attached with apologies to > those of you who have already seen it. I think that for hurricane > moderation marine cloud brightening allows better control of position than > the idea of circulation round a gyre. However the use for destratification > may be useful. > > Stephen > > > > *Emeritus Professor of Engineering Design* > > *School of Engineering* > > *University of Edinburgh* > > *Mayfield Road* > > *Edinburgh EH9 3DW* > > *Scotland* > > *0131 650 5704 or 0131 662 1180* > > *YouTube Jamie Taylor Power for Change* > > > > > > > > > > *From:* [email protected] <[email protected]> *On > Behalf Of *Ron Baiman > *Sent:* 20 February 2023 23:23 > *To:* Michael Hayes <[email protected]> > *Cc:* geoengineering <[email protected]>; > healthy-planet-action-coalition < > [email protected]>; Planetary Restoration < > [email protected]>; 'Eelco Rohling' via NOAC > Meetings <[email protected]>; Healthy Climate Alliance < > [email protected]>; Carbon Dioxide Removal < > [email protected]>; Jim Baird < > [email protected]>; Achim Hoffmann <[email protected]>; David > Mitchell <[email protected]>; Tom Goreau <[email protected]>; > Andrew Lockley <[email protected]> > *Subject:* Re: Potential "bottom up" cooling needs after net-zero? > > > > *This email was sent to you by someone outside the University.* > > You should only click on links or attachments if you are certain that the > email is genuine and the content is safe. > > Last sentence edit: > > > > *The question is whether there is any modeling of the balancing levels and > potential time scales for the GHG processes that would give some idea of > the needs and types of potentially necessary cooling and GHG draw down > processes.* > > > > > > On Mon, Feb 20, 2023 at 5:18 PM Ron Baiman <[email protected]> wrote: > > Thank you for the question Michael. > > > > My understanding is that the global warming impact of the "bottom up" heat > from the ocean in the models is closely related to the level of offsetting > cooling from natural (and other) GHG draw down from the atmosphere and the > Oceans. In other words, rates of natural GHG uptake in the Ocean, and draw > down from the atmosphere and ocean through other means, are key elements in > the long term modeling that could presumably also be impacted by applying > "bottom up" and "opening up" cooling techniques. The question is whether > there is any modeling of the balancing levels and potential time scales for > the GHG processes that would give some idea of the needs and types of > potentially necessary cooling processes. > > > > Ron Baiman > > > > > > Ron > > > > > > > > On Mon, Feb 20, 2023 at 4:48 PM Michael Hayes <[email protected]> > wrote: > > Ron, how does this relate to CDR? > > > > On Mon, Feb 20, 2023, 2:10 PM Ron Baiman <[email protected]> wrote: > > For more on the OTEC, WOXON, and CCT cooling methods see cooling paper > linked to here: https://www.healthyplanetaction.org/ > > > > On Mon, Feb 20, 2023 at 4:03 PM Ron Baiman <[email protected]> wrote: > > Dear Colleagues, > > > > In lieu of the recent research suggesting that we may be in for a warming > plateau of at least 50 years after net-zero due to the roughly offsetting > effects of continued ocean uptake of GHG and release of latent heat > accumulated in the ocean over many decades of warming (see: > https://www.carbonbrief.org/explainer-will-global-warming-stop-as-soon-as-net-zero-emissions-are-reached/) > does anyone know of modeling research on the potential need for "bottom up" > direct cooling at the point where the "warming from below" from the ocean > is greater than "the warming from above" from the sun? > > I'm thinking of techniques such as OTEC and WOHC (to harvest energy from > and cool the oceans) as well as CCT (to "open up" the clouds so as to > release more heat that has already been accumulated)? > > > > Thank you! > > > > Ron Baiman > > -- > You received this message because you are subscribed to the Google Groups > "NOAC Meetings" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/noac-meetings/CAPhUB9DtB_VDo-F03vQP1tt7Xaq863AUfrZXgVk3H0YQrtHUHw%40mail.gmail.com > <https://groups.google.com/d/msgid/noac-meetings/CAPhUB9DtB_VDo-F03vQP1tt7Xaq863AUfrZXgVk3H0YQrtHUHw%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > The University of Edinburgh is a charitable body, registered in Scotland, > with registration number SC005336. Is e buidheann carthannais a th’ ann an > Oilthigh Dhùn Èideann, clàraichte an Alba, àireamh clàraidh SC005336. > -- 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAPhUB9CLeiXUMmANHEjNrddAAmSWDakJyz4P_4atBBtgBwuTKA%40mail.gmail.com.
