Isn’t this trivially obvious? Yes, when decisions are ultimately made, they should explicitly consider the risks of any choice (to deploy or not, how much to deploy, etc). I’ve never heard a single person argue that we shouldn’t take the risks of solar geoengineering into account.
(And, of course, any rational engineer tries to identify strategies to reduce the probability of occurrence and the severity of impact, e.g., ensure multiple countries are capable of sustaining a deployment.) From: email@example.com [mailto:firstname.lastname@example.org] On Behalf Of Andrew Lockley Sent: Saturday, February 24, 2018 1:37 PM To: geoengineering <email@example.com> Subject: [geo] Solar geoengineering must take temperature debt into account - Andreas Oschlies Poster's note: others challenge these arguments. Parker and Irvine dispute the vulnerability of solar geoengineering to anything less than eg a nuclear war. Keith et al. suggest it can be temporarily deployed https://www.nature.com/articles/d41586-018-02203-x Solar engineering must take temperature debt into account Andreas Oschlies * * * <https://www.nature.com/magazine-assets/d41586-018-02203-x/d41586-018-02203-x.pdf> PDF version Solar geoengineering is a proposed method of climate engineering that aims to reduce global warming using an artificial ‘sunscreen’ of aerosols in Earth’s high atmosphere. As planning of the first field experiments gets under way, any potential risks associated with the technology must be transparently assessed and not downplayed or dismissed. One such risk of solar geoengineering is its ‘temperature debt’ — the planetary heating that would arise if maintenance of the artificial sunscreen was discontinued. Modelling suggests that most of the world’s population could benefit from this temporary sunscreen, compared with the adverse effects of unabated climate change (a questionable reference state, in my view). However, models also reveal the alarming rise in temperatures that could occur if the screen of short-lived aerosols should suddenly cease to function for any reason in the presence of high concentrations of long-lived greenhouse gases (see <http://dx.doi.org/10.1073/pnas.0700419104> H. D. Matthews and K. Caldeira Proc. Natl Acad. Sci. USA104, 9949–9954; 2007). This rapid warming would pose a severe risk to ecosystems and society. Even with the best planning to ensure steady operation of the technology, its continuous safe functioning and maintenance cannot be guaranteed. Yet it could take hundreds of years to safely phase out solar geoengineering and achieve the same degree of cooling by reducing greenhouse-gas concentrations. It is therefore imperative that, in the absence of a fail-safe mode for solar geoengineering, the temperature debt is fully accounted for in any assessments of this technology. Nature 554, 423 (2018) doi: 10.1038/d41586-018-02203-x -- 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 <mailto:geoengineering+unsubscr...@googlegroups.com> . To post to this group, send email to firstname.lastname@example.org <mailto:email@example.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 firstname.lastname@example.org. Visit this group at https://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout.