For me, the key thing is to determine how fast we have to deploy geoengineering to save the cities. Sea level rise is largely irreversible, so if we're hoping to have NYC and London in 100-300y then we desperately need to know what we need to do with geoengineering deployment. I find it surprising so little attention has been paid to this
We could be facing a potentially brutal choice in a decade or two - either cut temperatures dangerously fast, or lose the cities. Far better to start earlier, and not have to decide between those two evils. Andrew Lockley A On Sun, 15 Jul 2018, 15:10 Olivier Boucher, <olivier.bouc...@lmd.jussieu.fr> wrote: > Dear Andrew, > we performed such an experiment with HadGEM2-ES a while back, > see http://iopscience.iop.org/article/10.1088/1748-9326/7/2/024013 > We focused on various aspects of the C cycle (simplified as it is in such > a model). > We didn't look at sea level (too many terms involved that we do not > represent in the HadGEM model), but did show ocean heat content in fig 2g. > Basically there is an awful lot of intertia so it takes a long long time > before there is a change in sign during the ramp down. We also cite a > couple of studies which looked at sea level rise in the introduction (last > paragraph of section 1). > But the bottom line was that we could not find a lot of irreversibility > with our state-of-the-art ESM, mostly latency. It doesn't mean there isn't > irreversibility (ice sheet, permafrost, ...) but you would need more > complex models to study these. The little bit of irreversibility in ocean > nutrient came as a surprised. > > You may want to check who cited us > > https://scholar.google.fr/scholar?cites=2691382164698590876&as_sdt=2005&sciodt=0,5&hl=en > to find more recent studies on the subject. > > Also similar experiments are planned under CDRMIP so expect new papers > next year: > https://www.geosci-model-dev.net/11/1133/2018/ > > Best regards, > Olivier > > > > Is anyone modelling various ramp down scenarios for bringing temps down to > pre industrial over eg 0, 5, 10, 20, 50, 100 years? Would be interesting to > see how biosphere and sea level responds > > Andrew > -- > 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. > > > -- > ------------------------------ > Please check our NDC counter <https://gicn.shinyapps.io/NDC_Evaluation/> > released with our NDC paper > <http://iopscience.iop.org/article/10.1088/1748-9326/aaa0b9> > > -- > 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.
