The more advanced the process, the more momentum it has, and the harder it is to stop or reverse. It's unclear whether we could arrest mass loss, without driving the earth into a glacial period (colloquially, an ice age). I don't think there has been any serious modelling work done on ice loss reversal, or even if the models are capable of doing this with any useful accuracy.
On Sat, 15 Aug 2020, 12:03 Douglas MacMartin, <dgm...@cornell.edu> wrote: > What is not correct in the media report is this sentence: “This process, > however, would take decades.” Well, I guess arguably that’s true, it’s > just it would take a LOT of decades. Melt rate is currently of order > 1-2mm/yr equivalent SLR, so to get the 6m from melting all of Greenland > would take a few thousand years. Obviously it can speed up a lot, but > “hey, it’s losing mass” does not remotely imply “therefore we only have a > few decades before we lose our coastal cities”. So no, you can’t use this > study to claim that geoengineering is required to keep our coastal cities. > The problem with relying on mitigation+CDR is time-scale, but this study > doesn’t prove that our response time-scale needs to be faster than what CDR > can (at least hypothetically) provide. > > d > > *From:* geoengineering@googlegroups.com <geoengineering@googlegroups.com> *On > Behalf Of *Andrew Lockley > *Sent:* Saturday, August 15, 2020 3:40 AM > *To:* geoengineering <geoengineering@googlegroups.com> > *Subject:* [geo] Background-Greenland collapse > > > > If this study is correct https://www.nature.com/articles/s43247-020-0001-2 > > And is correctly reported here > https://mobile.reuters.com/article/amp/idUSKCN25A2X3 > > Then it appears to back up a point that I have been making for a long > time: geoengineering is required, if we are to keep our coastal cities. I > do not see economic or political feasibility for large scale CDR to tackle > historic emissions, and thus the task must fall to SRM. > > > > Nobody has managed to rause an objection to this argument to date. I'd be > grateful if those who might disagree were to raise counter arguments now. > > > > If the situation is as I understand it, prevarication has no clear > benefits, and we should thus move quickly to readiness for deployment. > > > > 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 view this discussion on the web visit > https://groups.google.com/d/msgid/geoengineering/CAJ3C-07%2BJc0dmp26W2_H08Rsrs1V_sjEs1pkG6xuZZ75OcTa%2Bw%40mail.gmail.com > <https://groups.google.com/d/msgid/geoengineering/CAJ3C-07%2BJc0dmp26W2_H08Rsrs1V_sjEs1pkG6xuZZ75OcTa%2Bw%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- 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 view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAJ3C-04pLr9SO5mJQXfUQUXxwUorOSNT1EgdO2AWLVv9Ba4h%2Bg%40mail.gmail.com.
