Perhaps this goes off the thread's subject a little, but since the dichotomy between 'test' & 'deployment' is here portrayed as one between a pulsed aerosol signal as the test and a sustained one as the deployment, has there been much playing around within models of the effects of differently pulsed releases and spatial arrangements as deployment itself, and then comparison of their effects in terms of hydrological perturbation?
Best, Nathan On Oct 22, 2:33 pm, Mike MacCracken <[email protected]> wrote: > I¹ll agree to that. Mike > > On 10/22/11 11:30 AM, "David Hawkins" <[email protected]> wrote: > > > > > My comment is not an argument against doing SRM research. It is an argument > > against trying to persuade people that SRM research is no different than > > tests > > of any other new technical systems. I doubt that is what Ken intended but I > > want to point out the importance of careful articulation of the rationales > > for > > SRM research and, more importantly, the need to acknowledge that SRM > > research > > will require extraordinary efforts to minimize risks that could emerge in > > course of such research at levels designed to produce significant forcing. > > > From: Mike MacCracken [mailto:[email protected]] > > Sent: Saturday, October 22, 2011 11:16 AM > > To: Hawkins, Dave; Ken Caldeira > > Cc: Doug MacMynowski; [email protected]; Geoengineering; > > [email protected] > > Subject: Re: [geo] Can We Test Geoengineering? paper and YouTube videos > > > True‹but we also don¹t know nearly everything about what ongoing GHG > > emissions > > will bring, so what we need to work toward, in my view, is a relative risk > > analysis. Not at all easy to do, but the question is not really SRM or not, > > but GHG without or with SRM. > > > Mike > > > On 10/22/11 8:49 AM, "David Hawkins" <[email protected]> wrote: > > Ken, > > You argue that we won't know everything about SRM deployment ahead of time > > but > > "this is no different than any test that is done of anything". I don't > > think > > this is helpful as a response to concerns about the challenges of designing > > protocols for an SRM research program. > > There are real differences in the risk profile for SRM tests that are > > intended > > to produce detectable forcing. This needs to be acknowledged and a research > > program needs to examine whether effective approaches to manage these risks > > can be developed. > > David > > > Sent from my iPad > > > On Oct 22, 2011, at 6:39 AM, "Ken Caldeira" <[email protected]> wrote: > > As Doug states below and I pointed out in our YouTube discussion, the > > question > > "Can geoengineering be tested?" is either trivially true or trivially false > > depending on what you mean by "tested". > > > If by "Can geoengineering be tested?" we mean "Is it in principle possible > > to > > perform tests that would give us more information about the likely > > consequences of an SRM deployment?", the answer is of course 'yes'. > > > If by this question we mean "Is it in principle possible to know everything > > one would like to know about the consequences of an SRM deployment prior to > > the deployment?", the answer is of course 'no'. > > > Fundamentally, this is no different than any test that is ever done of > > anything. Every test is designed to give us useful information; some tests > > are > > more useful than others; no test gives you the same information as a full > > deployment. > > > _______________ > > Ken Caldeira > > > Carnegie Institution Dept of Global Ecology > > 260 Panama Street, Stanford, CA 94305 USA > > +1 650 704 7212 <tel:%2B1%20650%20704%207212> > > [email protected] > > <mailto:[email protected]> > >http://dge.stanford.edu/labs/caldeiralab > > <http://dge.stanford.edu/labs/caldeiralab> @kencaldeira > > > See our YouTube: > > Sensitivity of temperature and precipitation to frequency of climate > > forcing: > > Ken Caldeira <http://www.youtube.com/watch?v=kDRYM_5S0AE> > > Her lab, mules, and carbon capture and storage: Sally Benson speaks to Near > > Zero <http://www.youtube.com/watch?v=oMJJn6eP8J0> > > > On Sat, Oct 22, 2011 at 2:06 PM, Doug MacMynowski <[email protected] > > <mailto:[email protected]> > wrote: > > Hi Ron, > > > My thanks for your comments too. Re your specific concern about CDR, I > > think > > that to the extent that those outside this list have an opinion associated > > with the word geoengineering, it is most likely associated with SRM, at > > least > > if they have negative connotations with the word. So I would agree that > > there¹s no advantage to CDR folk to use the word geoengineering. And > > personally, I see no disadvantage to SRM to use the word geoengineering, if > > that¹s what people already think it means. Of course, that¹s my guess, not > > formal research. > > > Re testing, a few comments (note of course, that we didn¹t script any of our > > discussions in the video, so some of those comments there may have lacked > > full > > caveats). > > 1. In response to Nadine, we certainly are not proposing testing, we > > simply believe that we need to understand what tests could tell us, since > > they > > could be a part of a strategy to manage risk (if we knew we could never > > test, > > that might alter our perspective) > > > 2. I do not think that ³can we test it² is really even a very > > well-posed > > question. Of course there are things we can learn. Of course there are > > things we can¹t learn. That¹s true for every test of anything; the real > > question is what we can or can¹t learn and what it would take. > > > 3. I do not think that anyone would ever conduct a test just because > > we > > wanted to know what SRM might do, so that we would then have it available as > > an option in case we needed it. That was what I intended to mean in saying > > that I didn¹t think it would ever be tested. > > > 4. However, if there is ever a point at which the risks of not doing > > SRM > > are clear and substantial to a sufficiently broad swath of population that > > it > > seems quite plausible that they outweigh the risks of doing SRM, then I do > > think that rather than simply turning things on at say 4 W/m2, it is > > reasonable to start smaller, and design the initial subscale deployment in a > > way that gives as much information as we can get as soon as possible. In > > that > > sense, I do believe that testing still has the potential to be useful as > > part > > of risk-reduction. > > > 5. SRM can still be a quick response to a ³climate emergency², but > > only > > if the emergency is sufficiently severe that we are willing to accept the > > risks of SRM. > > > 6. I don¹t think that anyone knows today whether the consequences of > > SRM > > will be negative for any region (relative to not doing SRM, that is.) I > > think > > that most studies suggest that that is actually not likely to be the case, > > but > > the reality is simply that we don¹t know (and I strongly disagree with the > > folks who imply that they do know). More research would help. > > > 7. And finally, I am neither an SRM proponent nor an opponent, and > > this > > paper was not intended to either be in favour or against it. I am simply in > > favour of sufficient research to understand it more. I do not personally > > think that anyone has sufficient information today to know whether > > implementing some form of SRM will be better or will not be better than not > > implementing it. (For pretty much any useful sense of the word better, > > which > > I acknowledge is ill-defined.) I know there are people on this list who > > disagree with me. > > > 8. And maybe one more pointŠ There were a couple of comments last year > > to the effect of geoengineering not being testable without full-scale > > implementation. If ³full-scale² means 4W/m2, then I think its clear we can > > learn useful information from a test that is smaller than that. If > > ³full-scale² means using enough radiative forcing so that the test itself > > could have unforeseen negative consequences, then I agree that any useful > > test > > would satisfy that criterion. In that very narrow sense, I agree with both > > Jim Fleming and Alan et al.¹s statements last year but I think its > > important > > to clear the record rather than leave impressions from over-simplified > > statements, since not everyone who read those statements would interpret > > them > > the same way. > > > doug > > > From: [email protected] > > <mailto:[email protected]> > > [mailto:[email protected] > > <mailto:[email protected]> ] On Behalf Of Ken Caldeira > > Sent: Friday, October 21, 2011 7:26 PM > > To: [email protected] <mailto:[email protected]> > > Cc: [email protected] <mailto:[email protected]> ; > > geoengineering; [email protected] > > <mailto:[email protected]> > > Subject: Re: [geo] Can We Test Geoengineering? paper and YouTube videos > > > Ron, > > > Thank you for your substantive comments. > > > You are correct that we are talking only about SRM and Marchetti spoke only > > about an approach to carbon storage -- something that today many (most?) > > people would not consider to be 'geoengineering'. > > > My own view is that the term 'geoengineering' is not particularly useful as > > it > > refers to an odd collection of things. I think it is impossible to define a > > set of properties for which there would be wide agreement that all things > > with > > those properties are 'geoengineering' and no things without those properties > > are 'geoengineering'. > > > Best, > > > Ken > > > PS. Thanks also for your stylistic comments on our videos. We are trying > > out > > this idea of making videos in an effort to improve communication. > > > I agree that the conversational style is more engaging than having one > > person > > speak. > > _______________ > > Ken Caldeira > > > Carnegie Institution Dept of Global Ecology > > 260 Panama Street, Stanford, CA 94305 USA > > +1 650 704 7212 <tel:%2B1%20650%20704%207212> > > [email protected] > > <mailto:[email protected]> > >http://dge.stanford.edu/labs/caldeiralab > > <http://dge.stanford.edu/labs/caldeiralab> @kencaldeira > > > See our YouTube: > > Sensitivity of temperature and precipitation to frequency of climate > > forcing: > > Ken Caldeira <http://www.youtube.com/watch?v=kDRYM_5S0AE> > > Her lab, mules, and carbon capture and storage: Sally Benson speaks to Near > > Zero <http://www.youtube.com/watch?v=oMJJn6eP8J0> > > > On Sat, Oct 22, 2011 at 9:11 AM, <[email protected] > > ... > > read more » -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
