Hi Ken - Clearly you're raising important points. As one who likely falls into your category of "somebody who believes that a certain class of experiments requires exceptional treatment by virtue of being a 'climate engineering experiment' or 'geoengineering experiment,'" I'll try to respond. By way of introduction, I have a biological science background and have followed climate science as a relatively educated layperson - my primary involvement in climate has been as an activist for 15 years. I am currently Executive Director of Biodiversity for a Livable Climate <http://bio4climate.org>, a non-profit that promotes sequestration of atmospheric carbon in soils using nature's primary tool for CDR, photosynthesis. We would call it geotherapy as opposed to geoengineering, since it is no-tech (well, an occasional iron tool or electric fence).
We well know that the natural world is extraordinarily complex and that our human capacity for understanding it and predicting its responses to our activities is limited at best. Granted, we've learned a great deal, and should continue to do so - it is one of our virtues as a species - but very very carefully. As anthropogenic global warming (AGW) demonstrates, our portfolio of unintended consequences runneth over. And that's the point. The issue with potential geoengineering experiments isn't "political correctness," it's fear. It's not irrational fear, either, any more than fear of a charging lion is irrational. I think we all consider AGW something to be feared - otherwise why have this list or even climate geoengineering as a formal pursuit in the first place? All species behavior has "unintended consequences," evolution is nothing if not unintended consequences (although the attribution of "intention" to the various kingdoms of life, 99.9% of which species have gone extinct over the past 4 billion years or so, may be a bit of a stretch). The unintended consequences of keystone species behavior can be vast, and often it's wonderful, from bacteria to beavers (how wonderful depends on one's point of view). Humans, of course, are a keystone species to beat the band, and since we generally consider ourselves primarily at issue here let's look at this from our point of view. To wit, we want *our* life-support systems to remain intact (we don't care much about life-support systems of dinosaurs or plague bacteria, etc.). And the unintended consequences of technology since the last ice age, but especially the last 300 years, have resulted in severely decimating our life-support systems. At some level most of us know this, therefore our technophobia has deep roots, no matter how much we love our technological adventures. I hope that this begins to address the political correctness question. With respect to "an operational definition that would allow a potential regulator to unambiguously determine whether a proposed experiment aimed at understanding climate consequences of aerosols does or does not constitute a 'climate engineering experiment' or 'geoengineering experiment,'" I understand and sympathize with your frustration, but I'm sure you realize that developing such an operational definition is not a trivial exercise. Nor are unambiguous determinations. One would have to develop non-destructive/non-interfering atmospheric experiments to assuage these concerns - obviously also not a trivial exercise. I have great respect for your work and that of climate scientists and related fields, and I wholeheartedly support better understanding of as many elements of the climate equation as possible, certainly including aerosol effects. But the geophysical world, like the biological world (an artificial boundary, at best), seems exquisitely sensitive to factors that may seem to us to be minimal (who would notice a 1°C change in ambient temperature, for example?). Hence the hesitation among many of us to apply geoengineering of any kind to a climate system already in disarray as a result of human technology. I would add that I think there's good evidence that the potential of soil sequestration renders most of geoengineering moot, at least in theory, but I'm sure that would turn into a protracted discussion - for another time. Best wishes, Adam On Friday, August 22, 2014 7:27:54 AM UTC-4, kcaldeira wrote: > > Isn't all of this excessive political correctness over potential > geoengineering experiments likely to make it more difficult to do > experiments aimed at better understand aerosol forcing? > > Can somebody who believes that a certain class of experiments requires > exceptional treatment by virtue of being a 'climate engineering experiment' > or 'geoengineering experiment' please provide me with an operational > definition that would allow a potential regulator to unambiguously > determine whether a proposed experiment aimed at understanding climate > consequences of aerosols does or does not constitute a 'climate > engineering experiment' or 'geoengineering experiment' ? > > > On Fri, Aug 22, 2014 at 11:41 AM, Andrew Lockley <[email protected] > <javascript:>> wrote: > >> Poster's note : those pesky clouds are still proving a source of much >> debate. Dealing with changes in forcings as aerosols are cleaned out in >> coming decades will be a major challenge. This could be the tipping point >> for SRM adoption. >> >> >> http://onlinelibrary.wiley.com/doi/10.1002/2014JD021670/abstract?utm_content=buffer8dee2&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer >> >> Keywords: >> >> aerosol;satellite-based estimate;direct forcing;indirect forcing >> >> Large uncertainties exist in estimations of aerosol direct radiative >> forcing (DRF) and indirect radiative forcing (IRF), and the values derived >> from global modeling differ substantially with satellite-based >> calculations. Following the approach of Quaas et al. (2008; hereafter named >> Quaas2008), we reassess satellite-based clear- and cloudy-sky radiative >> forcings and their seasonal variations by employing updated satellite >> products from 2004 to 2011 in combination with the anthropogenic aerosol >> optical depth (AOD) fraction obtained from model simulations using the >> GEOS-Chem-APM. Our derived annual mean aerosol clear-sky forcing (-0.59 >> Wm-2) is lower while the cloudy-sky forcing (-0.34 Wm-2) higher than the >> corresponding results (-0.9 Wm-2 and -0.2 Wm-2, respectively) reported in >> Quaas2008. Our study indicates that the derived forcings are sensitive to >> the anthropogenic AOD fraction and its spatial distribution but insensitive >> to the temporal resolution used to obtain the regression coefficients, i.e. >> monthly or seasonal-based. The forcing efficiency (i.e. the magnitude per >> anthropogenic AOD) for the clear-sky forcing based on this study is 19.9 >> Wm-2, which is about 5% smaller than Quaas2008's value of 21.1 Wm-2. In >> contrast, the efficiency for the cloudy-sky forcing of this study (11 Wm-2) >> is more than a factor of two larger than Quaas2008's value of 4.7 Wm-2. >> Uncertainties tests indicate that anthropogenic fraction of AOD strongly >> affect the computed forcings while using aerosol index (AI) instead of AOD >> from satellite data as aerosol proxy does not appear to cause any >> significant differences in regression slopes and derived forcings. >> >> -- >> 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 [email protected] <javascript:>. >> To post to this group, send email to [email protected] >> <javascript:>. >> Visit this group at http://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. 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