About a year and a half ago, I sent the authors of the paper under discussion the following comments:
*from Ken Caldeira <[email protected]>* *to [email protected]* *cc klaus keller <[email protected]>,* * Nancy Tuana <[email protected]>* *date Tue, Oct 27, 2009 at 9:39 AM* *subject cost of stopping suddenly* *I was browsing around the web and came across your document at: http://www.geosc.psu.edu/~kkeller/Goes_et_al_geoengineering_cc_2009_submitted.pdf Don't you think the risk of stopping geoengineering suddenly is rather overemphasized? Don't we do all sorts of things that would cause economic collapse if we stopped suddenly? What if we suddenly stopped extracting oil, mining coal, pumping gas, piping drinking water, hauling garbage, making electricity, etc, etc, etc? Doesn't modern life depend on continuing a wide range of practices which, if stopped suddenly, would lead to disaster? Isn't the response to this dilemma to place a high priority on making sure we continue these practices? Couldn't you rephrase the question of your paper as: What is the economic value of keeping geoengineering going once it is implemented? I think you would conclude that this would be a very high value activity. Normally, high value activities are seen as good things to do, not bad things.* ___________________________________________________ Ken Caldeira Carnegie Institution Dept of Global Ecology 260 Panama Street, Stanford, CA 94305 USA +1 650 704 7212 [email protected] http://dge.stanford.edu/labs/caldeiralab @kencaldeira On Tue, Apr 19, 2011 at 8:12 PM, Dan Whaley <[email protected]> wrote: > Seems to rehash so many of the canards, and to recommit so many of the > obvious fallacies.... sigh... are we condemned to a perpetual > groundhog day where even the Joe Romm's out there never pick up on the > main points? > > 0. We've got 700ppm baked in right now. So, mitigate, mitigate, > mitigate ain't going to cut it. > 1. SRM is not an either or, it's an AND. I don't see aerosol > geoengineering ever being substituted for emissions reductions-- in > other words, if we admit that we're in trouble, we'll likely take > action to address the root cause. Intelligent people might disagree-- > but I see it as a low probability outcome. > 2. The notion that if we started, we might somehow abruptly stop. > (This is akin to suddenly stopping the production of rice, or > microchips, for instance... sure, I suppose we could, but why would > we? It's not like we'd somehow forget how, or lose the ability to.) > 3. The concept that the Climate Intervention Bureau doesn't > effectively already exist. The IPCC/UNFCCC are already making a > determination that 2C is somehow the right number we should be aiming > at-- the geostat is already locked in. Precipitation impacts that > affect populations are already being decided. Why would the > deployment of strat aerosols be any different in nature than these > kinds of decisions? > 4. The notion that we need to make the decision about whether this is > good or bad mojo now, before we do the research to find out. > > D > > > On Apr 19, 7:35 pm, "Rau, Greg" <[email protected]> wrote: > > http://climateprogress.org/2011/04/17/aerosol-geoengineering-economics/ > > > > Science Sunday: “The economics (or lack thereof) of aerosol > geoengineering” > > Is the aerosol strategy intergenerationally unethical? > > April 17, 2011 > > Joe Romm > > > > The Gist: Putting reflective aerosols high into the atmosphere to slow > climate change is too risky and not cost effective. > > > > That’s Climate Central describing the core conclusions of the Climatic > Change paper “The economics (or lack thereof) of aerosol geoengineering,” > (full paper online here): > http://www3.geosc.psu.edu/~kzk10/Goes_et_al_geoengineering_cc_2009_su... > > > > This study would seem to support the view that if you don’t do aggressive > greenhouse mitigation starting now, you pretty much take aerosol > geo-engineering off the table as a very limited (but still dubious) add-on > strategy — as even geo-engineering experts like climatologist Ken Caldeira > have made clear. > > > > What’s nice about this study is that it doesn’t just do an economic > analysis, but also discusses intergenerational ethics. I’ll excerpt the > study itself at length — after the full Climate Central summary: > > > > Summary: Some have argued that if human society cannot sufficiently > reduce its greenhouse gas emissions, than we could still avoid the worst > consequences of global warming by putting highly reflective particles, known > as aerosols, high into the atmosphere. These aerosols would reflect light > back to space, thus counteracting warming from greenhouse gases. > > > > The authors of this paper use an integrated assessment model to determine > how costly such a method would be. The authors discuss the potential side > effects of this so-called “geoengineering” strategy, since adding aerosols > to the atmosphere could have unintended consequences, such as significantly > altering weather patterns and damaging stratospheric ozone. Also, aerosols > are short-lived, and would have to be continuously added to the atmosphere > in order for this scheme to work. If society stopped injecting them, the > result would be a rapid shift in the climate, something this paper argues > would be highly damaging. > > > > The authors calculate that if there is greater than a 15 percent chance > that such a method will be shut down, or if the unintended consequences of > aerosols are greater than half a percent of the world’s economy, then this > method of geoengineering is not worth the effort. > > > > And let’s not forget that the aerosol ’solution’ does nothing to stop the > consequences of ocean acidification, which recent studies suggest will be > devastating all by itself (see Geological Society: Acidifying oceans spell > marine biological meltdown “by end of century”). > > > > Here is the conclusion to the study itself: > > > > First, aerosol geoengineering hinges on counterbalancing the forcing > effects of greenhouse gas emissions (which decay over centuries) with the > forcing effects of aerosol emissions (which decay within years). Aerosol > geoengineering can hence lead to abrupt climate change if the aerosol > forcing is not sustained. The possibility of an intermittent aerosol > geoengineering forcing as well as negative impacts of the aerosol forcing > itself may cause economic damages that far exceed the benefits. Aerosol > geoengineering may hence pose more than just “minimal climate risks,” > contrary to the claim of Wigley (2006). Second, substituting aerosol > geoengineering for CO2 abatement fails an economic cost-benefit test in our > model for arguably reasonable assumptions. In contrast, (and as shown in > numerous previous studies) fast and sizeable cuts in CO2 emissions (far in > excess of the currently implemented measures) pass a costbenefit test. > Third, aerosol geoengineering constitutes a conscious temporal risk transfer > that arguably violates the ethical objectives of intergenerational justice. > > > > Our analysis has barely scratched the surface and is silent on many > important aspects. More than a decade ago, a Unites States National > Academies of Science committee assessing geoengineering strategies concluded > that “Engineering countermeasures need to be evaluated but should not be > implemented without broad understanding of the direct effects and the > potential side effects, the ethical issues, and the risks” (COSEPUP, 1992). > Today, we are still lacking this broad understanding. > > > > Caldeira made some similar points to me in a 2009 e-mail interview: > > > > Nobody has written about this that I know of, but …. > > > > If we keep emitting greenhouse gases with the intent of offsetting the > global warming with ever increasing loadings of particles in the > stratosphere, we will be heading to a planet with extremely high greenhouse > gases and a thick stratospheric haze that we would need to main[tain] > more-or-less indefinitely. This seems to be a dystopic world out of a > science fiction story. First, we can assume the oceans have been heavily > acidified with shellfish and corals largely a thing of the past. We can > assume that ecosystems will be greatly affected by the high CO2 / low > sunlight conditions — similar to what Earth experienced hundreds of millions > years ago. The sunlight would likely be very diffuse — maybe good for > portrait photography, but with unknown consequences for ecosystems. > > > > We know also that CO2 and sunlight affect Earth’s climate system in > different ways. For the same amount of change in rainfall, CO2 affects > temperature more than sunlight, so if we are to try to correct for changes > in precipitation patterns, we will be left with some residual warming that > would grow with time. > > > > And what will this increasing loading of particles in the stratosphere do > to the ozone layer and the other parts of Earth’s climate system that we > depend on? > > > > On top of all of these environmental considerations, there are > socio-political considerations: We we have a cooperative world government > deciding exactly how much geoengineering to deploy where? What if China were > to go into decades of drought? Would they sit idly by as the Climate > Intervention Bureau apparently ignores their plight? And what if political > instability where to mean that for a few years, the intervention system were > not maintained … all of that accumulated pent-up climate change would be > unleashed upon the Earth … and perhaps make “The Day After” movie look less > silly than it does. > > > > Long-term risk reduction depends on greenhouse gas emissions reduction. > Nevertheless, there is a chance that some of these options might be able to > diminish short-term risk in the event of a climate crisis. > > > > I would add the grave risk that that after injecting massive amounts of > sulfate aerosols into the atmosphere for a decade or more, we might > experience some unexpectedly bad side effect that just gets worse and worse. > After all, the top climate scientists underestimated the speed and scale of > greenhouse gas impacts (and the magnitude of synergistic ones, like bark > beetle infestations and forest fires). > > > > We would be in incompletely unexplored territory — what I call an > experimental chemotherapy and radiation therapy combined. There is no > possible way of predicting the long-term effect of the thick stratospheric > haze (which, unlike GHGs, has no recent or paleoclimate analog). If it > turned out to have unexpected catastrophic impacts of its own (other than > drought), we’d be totally screwed (see “the definitive killer objection to > geoengineering as even a temporary fix”). > > > > Or, rather, our children and grand-children would be totally screwed, not > that our actions today suggest we care about them very much (see Is the > global economy a Ponzi scheme?). The study has this to say about the > intergenerational ethics issue: > > > > While there have been careful analyses of the significance of > intergenerational justice in the wider context of climate change (Gardiner, > 2009; Page, 2006; Wolf, 2009), our study is the first to quantitatively > examine issues of intergenerational justice raised by aerosol geoengineering > for the case that aerosol geoengineering can be intermittent and the aerosol > forcing can cause harm. Our analysis shows, for example, that substituting > aerosol geoengineering for CO2 emissions abatement is a risk transfer from > current to future generations (Figures 4 to 7). In addition, the impacts of > the abrupt warming due to a discontinuation of the aerosol forcing would > place a heavy burden on human communities and ecosystem integrity (Alley et > al., 2002) and thus threaten the conditions required to satisfy basic > welfare rights of future generations. Substituting aerosol geoengineering > for CO2 emissions abatement decreases the required abatement costs in the > near term but imposes sizeable risks for more distant generations (Figure 4 > a, b). Since Rawlsian intergenerational distributive justice requires that > current generations avoid policies that create benefits for themselves but > impose costs on future generations, substituting aerosol geoengineering for > CO2 abatement fails on the grounds of this particular approach to ethics. > > > > It would appear that what science advisor John Holdren reasserted in 2009 > remains true today, “The ‘geo-engineering’ approaches considered so far > appear to be afflicted with some combination of high costs, low leverage, > and a high likelihood of serious side effects.“ > > > > Mitigate, mitigate, mitigate — or punish countless future generations. > > > > Related Post: > > > > Key ‘geoengineering’ strategy — cloud whitening — may yield warming, not > cooling > > Science on the Risks of Climate Engineering: “Optimism about a > geoengineered ‘easy way out’ should be tempered by examination of currently > observed climate changes” > > Share Print > > This entry was posted by Joe on Sunday, April 17th, 2011 at 5:13 pm > and is filed under Geoengineering. 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