Hi Nathan‹It is because of the potential (growing probability) of sea level rise that you mention that at least some of the effort on SLR should be devoted to exploring the potential for limiting sea level rise rather than using global average temperature as a metric. So, what might one do‹well, given that the accelerating ice sheet loss is due to energy from warming ocean waters, might not it make sense to be exploring the potential for cooling the Southern Ocean, the Labrador Sea/Davis Strait, etc. (and might some of the more local effects of the warmer waters reaching the glacial faces be moderated by wave-induced vertical mixing of surface and near-bottom waters)? Might it make sense as well to see if there is a way of promoting added snowfall over the ice sheets? As far back as the Caldeira-Wood paper it was evident that high-latitude global cooling via polar SRM does not reduce the extra flow of water vapor into polar regions because the water vapor increase is a result of additional moisture being evaporated at lower latitudes where solar radiation is not being reduced‹and that resulting cooling in high latitudes would lead to more of the precipitation in high latitudes being snow, hopefully tending to rebuild the glaciers and add mass to the ice sheets. Even ideas of pumping water onto ice sheets (or particular ice streams, etc.) needs to be explored‹and whatever else creative minds might come up with.
It just seems to me that, given the grave, seemingly inevitable, threat being faced (as mentioned by Rignot et al., etc.), efforts by the scientific community should be made to see if there is anything that might be done, and that doing so, even though the sea level rise will take longer to occur than a several degree C global warming, needs to be receiving some significant attention. Giving in to pessimism rather than exploring every possibility does not seem acceptable to me‹that the scientific community is not even getting the support needed to explore all the options is what is so particularly discouraging to me, and needs, in my view, to change. Best, Mike On 2/8/15, 12:33 PM, "Nathan Currier" <[email protected]> wrote: > Hi Mike, > > I wonder if you could explain a little more here on SLR as being a better > metric to set than temperature, because it seems to me like there's a > fundamental optimism behind saying this, and perhaps you can correct my overly > pessimistic assumptions...... > > The way that I have begun to imagine it is that the recent Rignot et al study > and other advances have started to make a picture where you have on-the-ground > observations of the bottom-up ice sheet mechanics in real time - the > grounding lines, retrograde beds, etc - and that this can be fit back in with > all the more general global paleoclimatic evidence to create a pretty coherent > view from which total 'sea level commitment' should be able to be estimated, > even if the future rate still could not without reverting to ice sheet models, > etc. Given that the Eemian level became 20-30 ft higher than current with CO2 > never going much higher than the pre-industrial 280ppm, and that we have > already reached a CO2 level and likely a net forcing that, if sustained, will > lead to ~75-120ft higher than now, is there any real grounds for hoping that > the total irreversible 'sea level commitment' is not already somewhere within > 30-120 ft? Given that the signals making the +30ft of the Eemian (not even > getting into the Holsteinian) were so mild, and now we've come along and put > such a whopper of a signal into the system, even if we dial it back very > quickly, let's say all the way back to 280, wouldn't it be hard to explain a > scenario where at least that same +30 ft is not still going to come due now? > If not, how could that be explained, since even the preindustrial level is > nothing like that at which new ice sheets get formed? And after all, in the > Rignot study, since Pine Island is so structurally vital to the WAIS, the now > irreversible 4ft of rise that was mentioned everywhere when the study was > published is clearly NOT the full commitment just from that area which we can > see in a very granular and detailed way - and that's pretty much irrespective > of global engineering of the surface temperature, too, it would seem. So, as > thermostats go, it might be like telling people they can set their house > between 40-55F - that is, just way far from any kind of comfort zone, even if, > of course, 30 ft is still a lot better than 120..... > > Now, I remember that you were once talking about some interesting measures, > far less controversial than "real geoengineering", that might be helpful for > SLR, like preventing icebergs from floating off from near outlets around > Greenland.....I wonder whether any more work has been done on this, and > whether such a technique might work well around the parts of WAIS recently > recognized as being hopeless, where it is the salinity gradient driving the > pumping of warmer waters down to the grounding line of the ice sheets, which > you might be able to interrupt in this manner? > > Cheers, > > Nathan > > > > > > > > On Tuesday, February 3, 2015 at 7:34:01 PM UTC-5, Mike MacCracken wrote: >> A bit delayed in responding to this email, but Tom Wigley had a paper in >> Science (copy attached) basically indicating that one would have to go back >> to preindustrial CO2 to stop sea level rise. An interesting research question >> might be how long one would need to return to a much lower radiative forcing >> to get sea level rise stopped before conditions could return to something >> like the 350 ppm CO2 level, so about as warm as one can be without the ice >> sheets losing mass. >> >> On this issue of ³setting the thermostat,² global average temperature might >> well not be the most important metric to be using. Precipitation has been >> mentioned, but it might well be that the rate of sea level rise would in the >> end be seen as being of much more relevance‹keeping a bit cooler only takes >> energy, relocating as a result of sea level rise is much more problematic >> (not just due to storm surge and inundation, but of salt water pressing into >> coastal aquifers, etc. And it might be much easier to get consensus on >> dealing with sea level rise than on a value for global average temperature. >> >> Mike MacCracken >> >> >> On 2/2/15, 6:59 AM, "Andrew Lockley" <[email protected] >> <http://[email protected]> > wrote: >> >>> I think that the assumption of a return to pre industrial is outmoded as an >>> intervention strategy. It's one I've heard much more from social scientists >>> than physical scientists, who typically look to prevent or reduce future >>> rises. >>> >>> The only reason to return to pre industrial would be to reverse tipping >>> point sea level rises, or others eg methane degassing from permafrost. >>> >>> As to the issue of disagreement and conflict, I'm absolutely with Jesse in >>> thinking this has been grossly overblown. I view this as a commonsense >>> position, and one that's sadly lacking from the literature. I'd strongly >>> encourage people to publish both discursive and modelling papers on the >>> issue. >>> >>> It's all too easy, apparently, for people to assume that consensus would be >>> unusually hard to achieve - without offering any evidence for this position. >>> >>> The world is not typically governed by force but by agreement. >>> >>> A >>> >>> On 2 Feb 2015 11:24, "J.L. Reynolds" <[email protected] >>> <http://[email protected]> > wrote: >>>> I generally believe that the concerns over potential conflict over solar >>>> climate engineering are often overblown. There will surely be disagreements >>>> among countries as to their desired temperatures. Yet often implied and >>>> sometimes explicitly stated in the CE discourse is that these disagreements >>>> would likely lead to armed conflict, and/or that they would render CE >>>> ineffective. Countries, including the powerful ones, routinely disagree >>>> over numerous things. My sense is that definitions and rules in the WTO and >>>> its agreements, for example, are much more consequential for them than CE >>>> would be. These conflicts are resolved through various sorts of bargaining. >>>> Perhaps I am excessively optimistic, but it seems that the nature of >>>> international conflict and resolution is fundamentally different (and more >>>> peaceful) than 100 years ago (to use Olaf¹s WW1 example), particularly >>>> among the powerful countries. Solar CE has the advantage, like much of >>>> international trade, that the advantages of countries¹ collective agreement >>>> would likely outweigh their potential, individual advantages of getting the >>>> climate which they desire. Disagreement could lead to various CE programs >>>> interfering with one another, and they would all be left worse off. That >>>> is, it is a resolvable collective action problem. >>>> >>>> From my vantage, the biggest concern would be if there were a systematic >>>> disagreement on the type and intensity of solar CE among powerful countries >>>> versus weak ones. The Ricke et al paper (which I recommend) cited by Ken >>>> begins to get at the that, but it also assumes that all countries would >>>> desire pre-industrial climates. That may not be the case. >>>> >>>> -Jesse >>>> >>>> ----------------------------------------- >>>> Jesse L. Reynolds, PhD >>>> Postdoctoral researcher >>>> Research funding coordinator, sustainability and climate >>>> European and International Public Law >>>> Tilburg Sustainability Center >>>> Tilburg University, The Netherlands >>>> Book review editor, Law, Innovation, and Technology >>>> email: [email protected] <http://[email protected]> >>>> <mailto:[email protected] <javascript:> > >>>> http://works.bepress.com/jessreyn/ <http://works.bepress.com/jessreyn/> >>>> >>>> >>>> From: [email protected] >>>> <http://[email protected]> [mailto:[email protected] >>>> <javascript:> ] On Behalf Of Ken Caldeira >>>> Sent: 31 January 2015 18:32 >>>> To: [email protected] <http://[email protected]> >>>> Cc: Motoko; geoengineering >>>> Subject: Re: [geo] Washington Post op ed >>>> >>>> >>>> Kate Ricke's model results are often trotted out to support the 'winners >>>> and losers' meme, but if you look at her results the conflict is between >>>> people who win less and people who win more. >>>> >>>> >>>> >>>> We did a follow-up study on political dynamics, using her results (see >>>> below). >>>> >>>> >>>> >>>> A key point to recognize is that, under typical climate damage metrics, the >>>> optimal amount of solar geoengineering for any given region differs from >>>> the global optimum typically by about 10%. That is, people would be >>>> arguing about the second digit, not the first digit. I doubt these second >>>> digit arguments will lead to any great conflict. >>>> >>>> >>>> >>>> The much greater conflict would likely to be whether to deploy a sulfate >>>> aerosol layer at all. If a consensus can be found to deploy, I doubt >>>> whether there will be that much conflict over subtle adjustments to the >>>> knob. >>>> >>>> >>>> >>>> http://iopscience.iop.org/1748-9326/8/1/014021/article >>>> >>>> >>>> >>>> Panel (a) shows on the vertical axis climate damage to different regions as >>>> a fraction of damages without solar geoengineering. The horizontal axis is >>>> th amount of solar geoengineering. Panels (b) and (c) show the optimum >>>> preferred by different regions. Note that they differ from the global >>>> optimum by only 10% or so. >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> _______________ >>>> Ken Caldeira >>>> >>>> Carnegie Institution for Science >>>> >>>> Dept of Global Ecology >>>> >>>> 260 Panama Street, Stanford, CA 94305 USA >>>> +1 650 704 7212 <tel:%2B1%20650%20704%207212> >>>> [email protected] <http://[email protected]> >>>> http://dge.stanford.edu/labs/caldeiralab >>>> >>>> https://twitter.com/KenCaldeira >>>> >>>> >>>> >>>> My assistant is Dawn Ross <[email protected] >>>> <http://[email protected]> >, with access to incoming emails. >>>> >>>> >>>> >>>> >>>> >>>> >>>> On Sat, Jan 31, 2015 at 7:54 AM, Cush Ngonzo Luwesi <[email protected] >>>> <http://[email protected]> > wrote: >>>> >>>> I partly agree with Andy: Skepticism yes but realism is also needed. Alvin >>>> Toffler (1970) predicted the ³future shock² that ³change denial² will cause >>>> in the anthropocene. He used an analogy from the transmission of sound >>>> through electrical cables, which until 1875, was unconceivable by some >>>> while M. Bell was inventing the first telephone. Thence, he called for >>>> improved anticipation in governance to mitigate that future shock and >>>> ensure a smooth transition from hold practices to the new technological >>>> environment with the pace of social and technical change (Jasanoff, 2011; >>>> Stilgoe et al., 2013). Nonetheless, Toffler (1970) argued that not all >>>> technological and scientific discoveries would come out from the >>>> laboratories and take place nor would they see the light; some would just >>>> abort while others would vanish in the impasse, owing to their >>>> unfeasibility or fanciness or even disconnection to reality and >>>> disconcertion. This corroborate with the recent Royal Society¹s Berlin >>>> Declaration 2014 on geoengineering. >>>> >>>> >>>> >>>> Dr Cush Ngonzo Luwesi, PhD >>>> >>>> Lecturer >>>> >>>> Department of Geography >>>> >>>> Kenyatta University >>>> >>>> >>>> >>>> On Sat, Jan 31, 2015 at 3:24 PM, Motoko <[email protected] >>>> <http://[email protected]> > wrote: >>>> >>>> Great reference. I want to add the following sentence of von Neumann: "All >>>> experience shows that even smaller technological changes than those now in >>>> the cards profoundly transform political and social relationships." >>>> >>>> Von Neumann could be right in assuming that climate control will change a >>>> lot. It will change also the relationship of science and policy. >>>> >>>> Am 30.01.2015 um 22:37 schrieb Jim Fleming: >>>> >>>>> As argued in 1955: >>>>> >>>>> "Present awful possibilities of nuclear warfare may give way to others >>>>> even more >>>>> >>>>> awful. After global climate control becomes possible, perhaps all our >>>>> present >>>>> >>>>> involvements will seem simple. We should not deceive ourselves: >>>>> >>>>> once such possibilities become actual, they will be exploited." >>>>> >>>>> -- John von Neumann, ³Can We Survive Technology?² Fortune, June 1955, >>>>> 106108. >>>>> >>>>> >>>>> James R. Fleming >>>>> >>>>> Professor of Science, Technology, and Society, Colby College >>>>> >>>>> Research Associate, Columbia University >>>>> >>>>> Series Editor, Palgrave Studies in the History of Science and Technology, >>>>> bit.ly/THQMcd <http://bit.ly/THQMcd> <http://bit.ly/THQMcd> >>>>> >>>>> Profile: http://www.colby.edu/directory/profile/jfleming/ >>>>> <http://www.colby.edu/directory/profile/jfleming/> >>>>> >>>>> >>>>> >>>>> >>>>> On Fri, Jan 30, 2015 at 11:00 AM, Olaf Corry <[email protected] >>>>> <http://[email protected]> > wrote: >>>>> >>>>> >>>>> I agree with the basic idea that the politics of this will be likely to be >>>>> very tricky (although - and partly for that reason - I remain unconvinced >>>>> by the other premise of the article that SPI has been overwhelmingly shown >>>>> to have net life-saving potential). >>>>> >>>>> >>>>> >>>>> Andrew, why the incredulity at a conflict scenario? The thing about >>>>> international relations is that outcomes do not always reflect intentions >>>>> or desired collective outcomes. History is full of consensus processes >>>>> breaking down and collectively sub-optimal (to put it mildly) outcomes. >>>>> Presumably everybody had an incentive to avoid the chaos of WW1 and stick >>>>> to a consensus process... >>>>> >>>>> >>>>> >>>>> So the authors are right in my opinion to raise this problem regarding >>>>> SRM. I would add that by complicating/souring the international diplomatic >>>>> situation SRM could easily affect the ability to agree and cooperate >>>>> internationally on mitigation and adaptation too, which we agree would >>>>> still need to happen as fast as possible. >>>>> >>>>> >>>>> >>>>> If we are consistently outcome-ethical about it we probably shouldn't put >>>>> the politics in one compartment and the evaluation of the technology in >>>>> another one. >>>>> >>>>> >>>>> >>>>> Best regards >>>>> >>>>> Olaf Corry >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> On Friday, 30 January 2015 09:18:54 UTC, andrewjlockley wrote: >>>>> I disagree fundamentally with the premise of this article. >>>>> >>>>> A decision on climate has to be made. Everyone knows it. Everyone has an >>>>> incentive to avoid chaos. Therefore, people have a very large incentive to >>>>> stick to a consensus process, because anyone who doesn't stick will >>>>> instantly break that consensus and cause chaos - which is a guaranteed >>>>> loser for all. >>>>> >>>>> Same reason villagers don't burgle their neighbours when police are busy >>>>> elsewhere dealing with a major incident. >>>>> >>>>> A >>>>> >>>>> On 30 Jan 2015 08:54, "Andy Parker" <[email protected] >>>>> <http://[email protected]> > wrote: >>>>> >>>>> Hey folks, the Washington Post just published an op ed on the messy >>>>> politics of solar geoengineering, written by David Keith and me: >>>>> http://www.washingtonpost.com/opinions/whats-the-right-temperature-for-the >>>>> -earth/2015/01/29/b2dda53a-7c05-11e4-84d4-7c896b90abdc_story.html -- 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]. 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