Andrew, At this point we are looking for actual geomechanical analysis with numbers.
Piling speculation upon speculation is not helpful. Best, Ken On Wed, Aug 1, 2018, 08:28 Andrew Lockley <andrew.lock...@gmail.com> wrote: > Large explosive charges, tens or hundreds of metres beneath the sea bed, > would create a crater with an elevated ring of debris. This ring would tend > to jam ice in an otherwise smooth sea bed, if it was tall enough to > protrude into the surface waters. > > I understand that the Russians had a significant, although experimental, > programme of civil engineering using nuclear explosives in the early cold > War. > > Andrew > > On Wed, 1 Aug 2018, 07:18 Ken Caldeira, <kcalde...@carnegiescience.edu> > wrote: > >> Below is what I wrote to a writer for the Atlantic, Robinson Meyer: >> https://www.theatlantic.com/science/archive/2018/01/a-new-geo-engineering-proposal-to-stop-sea-level-rise/550214/ >> >> What got into the piece was: >> >> Ken Caldeira, a climate scientist at the Carnegie Institution for >> Science, said that he would want to hear from engineers before investing >> further in a seafloor plan. “Without some numbers and some consultation >> with engineers, it is just a modeling thought experiment,” he said in an >> email. “I do not have the expertise to evaluate this proposal, but I am >> quite skeptical.” >> >> >> Ken Caldeira <kcalde...@carnegiescience.edu> >> Tue, Jan 2, 4:56 PM >> to Robinson >> Hi, my initial reaction would be to say that an engineering feat at a >> scale likely to have a substantial effect on global sea level would be >> impractical in the real world, but I am saying that without having access >> to any real numbers. >> >> Has the postdoc calculated what pressures the glaciers would be imposing >> on the sill and what kind of engineered structure would be able to >> withstand those pressures? >> >> Does the postdoc have estimates of the size (height x width) of the >> artificial sills, and how much sea level rise sills of those scales >> would be expected to forestall? >> >> Without some numbers and some consultation with engineers, it is just a >> modeling thought experiment. >> >> --- >> >> One could also imagine, for example, some system to prevent sea-ice from >> spreading away from the poles towards equators (perhaps a systems of cables >> or something?). >> >> Sea-ice forms closer to the poles and then blows equatorward where it >> tends to melt. Perhaps sea ice could be maintained by mechanically >> preventing it from being transported equatorward. One could do a simulation >> in a climate model and show that this would likely help preserve sea ice, >> but if there is no real engineering system that could effect this at a >> conceivable cost, then it is just a modeling thought experiment. >> >> Best, >> Ken >> >> Ken Caldeira <kcalde...@carnegiescience.edu> >> Mon, Jan 8, 8:09 PM >> to Robinson >> Robinson, >> >> I think you need to talk to people who know about ice sheets, people who >> know something about material properties of "aggregate material", and >> people who know something about building structures underwater. >> >> I am none of these and so unable to give this any kind of sensible >> evaluation. >> >> Glaciers regularly plow a great deal of material ahead of them, and >> mountain glaciers routine carve wide swaths through solid rock. >> >> My guess is that the stresses that the ice sheet would impose on a bunch >> of aggregate would be so large the ice sheet would plow right through it >> but I am not expert on such mechanical properties. >> >> I do not have the expertise to evaluate this proposal, but I am quite >> skeptical. >> >> Best, >> Ken >> >> >> *Ken Caldeira* >> *Carnegie Institution for Science* >> Dept of Global Ecology / Carnegie Energy Innovation >> 260 Panama St, >> <https://maps.google.com/?q=260+Panama+St,%C2%A0+Stanford+CA+94305+USA+%2B1+650&entry=gmail&source=g>Stanford >> CA 94305 USA >> <https://maps.google.com/?q=260+Panama+St,%C2%A0+Stanford+CA+94305+USA+%2B1+650&entry=gmail&source=g> >> +1 650 >> <https://maps.google.com/?q=260+Panama+St,%C2%A0+Stanford+CA+94305+USA+%2B1+650&entry=gmail&source=g> >> 704 7212 kcalde...@carnegiescience.edu >> http://CarnegieEnergyInnovation.org >> http://dge.stanford.edu/labs/caldeiralab >> <http://dge.stanford.edu/labs/caldeiralab> >> >> Assistant, with access to incoming emails: Jess Barker >> jbar...@carnegiescience.edu >> >> >> >> >> >> On Wed, Aug 1, 2018 at 12:37 AM Veli Albert Kallio < >> albert_kal...@hotmail.com> wrote: >> >>> >>> >>> >>> * Our Changing Climate in Action: the Risk of Global Warming and the >>> Environmental Damage from the Rising Ocean Water Table | Sustainable Seas >>> Enquiry | Written evidence submitted by Veli Albert Kallio, FRGS (SSI0121) >>> | Ordered to be published 23 May 2018 by the House of Commons. * >>> *Abstract:* >>> >>> Recently NATURE published a discussion on construction of sills in >>> attempt to prevent or slow melting glaciers that are discharging ice into >>> the ice fjords. Several further papers promptly followed publication of >>> this essentially erroneous article in a respected NATURE magazine. Here it >>> is pointed out that there is a discrepancy of several magnitudes thus >>> excluding a long-term viability to manage the edges of ice fjords or >>> continental ice shelves/sheets due to a phenomenon known as the >>> mega-erratics. These are blocks of hard rocks that are several kilometres >>> in size that have been dislocated by a warmed and wet edges of glacier/ice >>> sheet/ice shelf. This Parliament evidence points out the error that was not >>> apparent to the peer-reviewers at the time and in subsequent papers that >>> followed. The Parliament was shown evidence that large enough obstacles >>> cannot be possibly made to prevent ice discharges due to a progression of >>> melting, that softens and lubricates glaciers, ice caps and ice sheets. The >>> forces unleashed by the ice front exceeds several magnitudes from the >>> conceived objects that sills were proposed. The only, and very only effect >>> is temporary and limited to prevention of warm water incursion where these >>> methods will work for a while in a cold, dry, and relatively stable ice >>> formations. A long-term projections suggested to prevent warmed and >>> water-infested glaciers from discharging ice into the ocean cannot be made >>> as the forces of ice exceed many magnitudes of the sills and levies that >>> can be made of concrete blocks, aggregates or other materials. Thus the >>> prevention of sea level rise by this method for centuries or millennia is >>> not functional one and thus the mitigation and prevention of rubbish gyros >>> in ocean, the supply of housing, nuclear and food production security must >>> be looked at as solution by the ocean littoral states. Several examples of >>> various types of risk to the sustainability of oceans have been presented >>> in addition to the above exposed misconception. This comes with much regret >>> as it appears that one 'hoped-for-solution' to manage the future climate >>> change impacts has largely foundered on the issue that the sills cannot be >>> made strong enough to contain most important, warmed glaciers or edges of >>> unstable ice shelves. However, for a short-term this may offer small-scale >>> solutions provided that costs remain sufficiently small. Aggressively >>> melting ice formations with darkened surfaces, wide spread melt water >>> ponds, or water filled crevasses it does not offer much, if any, prolonged >>> ice stability. (The document is best viewed as a .pdf file due to the >>> lay-out of graph and legends.) >>> >>> >>> https://www.academia.edu/37157851/Our_Changing_Climate_in_Action_the_Risk_of_Global_Warming_and_the_Environmental_Damage_from_the_Rising_Ocean_Water_Table_Sustainable_Seas_Enquiry_Written_evidence_submitted_by_Veli_Albert_Kallio_FRGS_SSI0121_Ordered_to_be_published_23_May_2018_by_the_House_of_Commons >>> >>> <https://www.academia.edu/37157851/Our_Changing_Climate_in_Action_the_Risk_of_Global_Warming_and_the_Environmental_Damage_from_the_Rising_Ocean_Water_Table_Sustainable_Seas_Enquiry_Written_evidence_submitted_by_Veli_Albert_Kallio_FRGS_SSI0121_Ordered_to_be_published_23_May_2018_by_the_House_of_Commons> >>> Our Changing Climate in Action: the Risk of Global Warming and the >>> Environmental Damage from the Rising Ocean Water Table | Sustainable Seas >>> Enquiry | Written evidence submitted by Veli Albert Kallio, FRGS (SSI0121) >>> | Ordered to be published 23 May >>> <https://www.academia.edu/37157851/Our_Changing_Climate_in_Action_the_Risk_of_Global_Warming_and_the_Environmental_Damage_from_the_Rising_Ocean_Water_Table_Sustainable_Seas_Enquiry_Written_evidence_submitted_by_Veli_Albert_Kallio_FRGS_SSI0121_Ordered_to_be_published_23_May_2018_by_the_House_of_Commons> >>> Recently NATURE published a discussion on construction of sills in >>> attempt to prevent or slow melting glaciers that are discharging ice into >>> the ice fjords. Several further papers promptly followed publication of >>> this essentially erroneous article in >>> www.academia.edu >>> >>> >>> ------------------------------ >>> *From:* geoengineering@googlegroups.com <geoengineering@googlegroups.com> >>> on behalf of Andrew Lockley <andrew.lock...@gmail.com> >>> *Sent:* 27 July 2018 10:08 >>> *To:* geoengineering >>> *Subject:* [geo] Stopping the Flood: Could We Use Targeted >>> Geoengineering to Mitigate Sea Level Rise? >>> >>> Stopping the Flood: Could We Use Targeted Geoengineering to >>> Mitigate Sea Level Rise? >>> Michael J. Wolovick1 >>> and John C. Moore2,3 >>> 1Atmosphere and Ocean Sciences Program, Department of Geosciences, >>> Princeton University, GFDL, 201 Forrestal Road, >>> <https://maps.google.com/?q=201+Forrestal+Road,+%0D%0A+Princeton,+NJ+08540,+USA&entry=gmail&source=g> >>> Princeton, NJ 08540, USA >>> <https://maps.google.com/?q=201+Forrestal+Road,+%0D%0A+Princeton,+NJ+08540,+USA&entry=gmail&source=g> >>> >>> <https://maps.google.com/?q=201+Forrestal+Road,+%0D%0A+Princeton,+NJ+08540,+USA&entry=gmail&source=g> >>> 2College of Global Change and Earth System Science, Beijing Normal >>> University, Beijing, China >>> 3Arctic Centre, University of Lapland, Finland >>> Correspondence: M.J. Wolovick (wolov...@princeton.edu) >>> Abstract. The Marine Ice Sheet Instability (MISI) is a dynamic feedback >>> that can cause an ice sheet to enter a runaway collapse. >>> Thwaites Glacier, West Antarctica, is the largest individual source of >>> future sea level rise and may have already entered the >>> MISI. Here, we use a suite of coupled ice–ocean flowband simulations to >>> explore whether targeted geoengineering using an >>> artificial sill or artificial ice rises could counter a collapse. >>> Successful interventions occur when the floating ice shelf regrounds >>> 5 on the pinning points, increasing buttressing and reducing ice flux >>> across the grounding line. Regrounding is more likely with a >>> continuous sill that is able to block warm water transport to the >>> grounding line. The smallest design we consider is comparable >>> in scale to existing civil engineering projects but has only a 30% >>> success rate, while larger designs are more effective. There >>> are multiple possible routes forward to improve upon the designs that we >>> considered, and with decades or more to research >>> designs it is plausible that the scientific community could come up with >>> a plan that was both effective and achievable. While >>> 10 reducing emissions remains the short-term priority for minimizing the >>> effects of climate change, in the long run humanity may >>> need to develop contingency plans to deal with an ice sheet collapse. >>> >>> -- >>> 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+unsubscr...@googlegroups.com. >>> To post to this group, send email to geoengineering@googlegroups.com. >>> Visit this group at https://groups.google.com/group/geoengineering. >>> For more options, visit 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+unsubscr...@googlegroups.com. >>> To post to this group, send email to geoengineering@googlegroups.com. >>> Visit this group at https://groups.google.com/group/geoengineering. >>> For more options, visit 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+unsubscr...@googlegroups.com. >> To post to this group, send email to geoengineering@googlegroups.com. >> Visit this group at https://groups.google.com/group/geoengineering. >> For more options, visit 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+unsubscr...@googlegroups.com. To post to this group, send email to geoengineering@googlegroups.com. Visit this group at https://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout.
