If you look at current emissions (too high and still rising slightly), plus the lock-in effect of current and near-term planned infrastructure (e.g. the WRI report on massive planned worldwide coal plant additions), I don't think it even makes sense to discuss CDR as anything but an active form of mitigation of net emissions. The notion that we'll significantly reduce atmospheric CO2 below the current level during the lifetime of anyone reading this is unwarrantedly optimistic. Similarly, I don't think there's any point in worrying about returning to 280ppm too quickly, if ever (in any time frame meaningful to current civilization), simply because of the scale of the problem. The effort needed to suck over 100ppm of CO2 from the atmosphere more than we emit over a couple of centuries and permanently sequester it would be beyond anything humanity has accomplished to date.
I do think we will have to and will employ CDR, possibly in several forms. But we will also have to guard against it being seen as a reason for reduced urgency about reducing emissions. I'm very concerned that any non-trivial CDR effort will lead to the perception among the usual suspects (add your own list) that the situation isn't as bad as it was in the recent, non-CDR-ing past, and therefore they have a more time to bring down emissions. The goal can't merely be to stop increasing atmospheric CO2 levels, but to reduce them as quickly as we can, which will still be very slowly. On Tuesday, July 2, 2013 4:18:39 PM UTC-4, andrewjlockley wrote: > > I think a better argument against CDR is that it's so slow to act that you > probably wouldn't want to pull down the temperature once it's been high for > so long. > > Would we really want to go right back to pre industrial temperatures > today? If not, why should we assume that future generations will want to go > back to today's climate? Why will they want to go back at all? > > Prevention of rises is preferable to facilitating falls. CDR can't do > that, in practice. > > A > On Jul 2, 2013 8:43 PM, "Rau, Greg" <ra...@llnl.gov <javascript:>> wrote: > >> Klaus Lackner and I tried to inject some hope and optimism into the >> earlier climate change mitigation discussion by Matthews and Solomon: >> http://www.sciencemag.org/content/340/6140/1522.2.full >> >> M&S reply: >> http://www.sciencemag.org/content/340/6140/1523.1.full >> >> They summarize: >> "In a discussion of the potential for immediate or near-future action to >> slow the growth of atmospheric CO2, we suggest that consideration of >> carbon dioxide removal (or other geoengineering) technologies would at best >> be not very relevant, and at worst could distract from the imperative of >> decreasing investment in energy technologies that lead to large CO2 >> emissions." >> >> Message to CRDer's: Put down those pencils and back away from the black >> board - you are distracting the geniuses who are going to reduce CO2 >> emissions and you are a potential menace to the planet. That goes double >> for SRMer's. >> >> Greg >> >> -- >> 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 geoengineerin...@googlegroups.com <javascript:>. >> To post to this group, send email to geoengi...@googlegroups.com<javascript:> >> . >> Visit this group at http://groups.google.com/group/geoengineering. >> For more options, visit https://groups.google.com/groups/opt_out. >> >> >> > -- 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 http://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/groups/opt_out.
