reference [1] http://unfccc.int/essential_background/convention/background/items/1355.php
On Sat, Jul 23, 2011 at 11:43 PM, John Nissen <johnnissen2...@gmail.com>wrote: > > Ken, > > We all like to be optimistic - it is a human characteristic. But if you > accept what is happening to the Earth System, as being discovered by people > like Hansen, Wadhams and Shakhova (on climate sensitivity, sea ice retreat > and Arctic methane respectively), then the situation is dire for every human > on this planet. This is not a question of perspective, but an appreciation > of what appears to be very likely happening, as argued by scientists working > in the field, looking at the data - and not clouding their judgement by > wishful thinking. None of us wants to see this. It is very difficult to > believe that it's happening to us. You look out at our beautiful planet, > and enjoy the fruits (mulberries today!), and it's almost impossible to > believe that this could all change - if we do not act very quickly and > effectively, on several fronts. > > As for geoengineering perhaps not working as well as expected, this is all > the more reason for starting sooner, and starting on several different > methods in parallel. Any of the methods being proposed can easily be > stopped, if it's not having the required effect - or an adverse effect is > too great. The greatest danger is being too late - and then who we have to > blame but ourselves - us, who have seen the facts of the situation. > > Most importantly we must inform our political leaders. If the situation is > acknowledged by any country as the emergency, even without 100% scientific > certainty, then they are obliged to take action for the sake of their own > citizens, according the UNFCCC Article 3 [1]. It's our duty, as people who > understand what is happening to the Earth System, not to shelter under > misplaced optimism, but come into the open and declare the emergency - if > that's the conclusion from what is being discovered. > > John > > --- > > > On Sat, Jul 23, 2011 at 3:36 PM, Ken Caldeira <kcalde...@gmail.com> wrote: > >> John, >> >> I have no doubt that, from the perspective of many extant species and >> less-fortunate humans, we are indeed in dire straits. >> >> If I were convinced that stratospheric aerosols would work as advertised >> and that there would be no unforeseen or unanticipated repercussions, and >> that some sort of democratic process could be devised to give the overall >> effort political legitimacy, then I would be in favor of early deployment of >> such schemes. >> >> However, I am confident that were such systems deployed, there would be >> surprises. Maybe the surprise would be how well it works and how everyone >> the world over greets the project with such a high degree of appreciation. >> On the other hand, the surprise could be that things go rather wrong, >> exacerbating international friction, leading to economic disruption, wars, >> etc. >> >> Before such systems would be deployed, I would hope that the risk-benefit >> balance would be very clearly tipped in the direction of benefit. I just do >> not think we are there yet. >> >> Best, >> >> Ken >> >> >> ___________________________________________________ >> Ken Caldeira >> >> Carnegie Institution Dept of Global Ecology >> 260 Panama Street, Stanford, CA 94305 USA >> +1 650 704 7212 kcalde...@carnegie.stanford.edu >> http://dge.stanford.edu/labs/caldeiralab @kencaldeira >> >> >> >> On Sat, Jul 23, 2011 at 12:08 AM, John Nissen >> <johnnissen2...@gmail.com>wrote: >> >>> Hi Ken, >>> >>> You take a fundamentally different view of the Earth System and >>> geoengineering. I see the Earth System as in an extremely precarious state >>> and geoengineering as absolutely necessary to nudge the system back into a >>> state that allows continued habitation of the planet by ourselves and our >>> offspring. Do you really think that we can survive the century simply by >>> reducing carbon emissions? If we wait for some dramatic event, like >>> disappearance of Arctic sea ice, as an "emergency" sufficient to justify >>> geoengineering, don't we risk leaving geoengineering too late? >>> >>> For me, geoengineering is like chemotherapy when a vital organ has >>> cancer, or like fire-fighting when parts of the burning building contain >>> explosives. You start tackling the problem as quickly as you possibly can, >>> concentrating on the critical parts. >>> >>> John >>> >>> --- >>> >>> >>> On Fri, Jul 22, 2011 at 4:02 PM, Ken Caldeira <kcalde...@gmail.com>wrote: >>> >>>> Two points: >>>> >>>> I am not opposed to scientists making prescriptive statements in their >>>> roles as citizens. >>>> >>>> However, I am opposed to prescriptive statements (statements about what >>>> we should do) in peer-reviewed scientific papers. >>>> >>>> I think science is about establishing objective facts about the world. >>>> As citizens, we take these facts and our values and make judgments about >>>> what we should do. >>>> >>>> I am 100% in favor of Jim Hansen making prescriptive statements. I would >>>> just prefer that he not do it in the context of a peer-reviewed scientific >>>> paper. >>>> >>>> Science cannot tell us what to do. It can give us information which we >>>> can use to make decisions. >>>> >>>> If the science gets mixed up with politics in peer-reviewed scientific >>>> publications, I think it ends up weakening the credibility of the entire >>>> scientific publication process (since statements whose truth value cannot >>>> be >>>> empirically established are obviously getting past reviewers). >>>> >>>> I should say that the worst in this respect are the economists, who >>>> insist that they should be regarded as a science while simultaneously >>>> trying >>>> to tell us what we should be doing. >>>> >>>> --- >>>> >>>> On deployment of some sort of solar reflection system: all of our model >>>> results indicate that a high co2 world with deflection of some sunlight >>>> would be more similar to a low co2 world than is a high co2 world without >>>> deflection of sunlight. >>>> >>>> So, do I think that direct environmental damage from greenhouse gases >>>> could be diminished by deploying such a system? Yes, probably although I >>>> am >>>> not 100% certain of this. >>>> >>>> Do I think near-term deployment will reduce overall risk and improve >>>> long-term well-being? Of this I am less certain, as it is hard to predict >>>> the various sociopolitical, as well as environmental, repercussions that >>>> might occur. >>>> >>>> Ken Caldeira >>>> kcalde...@carnegie.stanford.edu >>>> +1 650 704 7212 >>>> http://dge.stanford.edu/labs/caldeiralab >>>> >>>> Sent from a limited-typing keyboard >>>> >>>> On Jul 22, 2011, at 16:38, John Nissen <johnnissen2...@gmail.com> >>>> wrote: >>>> >>>> >>>> >>>> Dear Ken, >>>> >>>> I've already looked at this interesting paper [1], from Jim Hansen and >>>> Mikiko Sato - but I'd not read before of his conjecture about rate of ice >>>> mass loss doubling per decade, producing many metres of sea level rise this >>>> century. But the implication is that the situation can be saved simply by >>>> reducing fossil fuel emissions! Is that the prescription that you are >>>> complaining about? Wouldn't a well-considered prescription be welcome from >>>> somebody as eminent as Prof Hansen? Geoengineering for example! I don't >>>> see a way out of our predicament without it. Do you, Ken? >>>> >>>> Does Hansen accept that 90% sea ice could be gone as soon as at end >>>> summer 2016? (BTW, I've another reference to this date we've been arguing >>>> about [2].) >>>> >>>> Hansen seems to dismiss methane as always producing less forcing than >>>> CO2: >>>> >>>> "*This sensitivity has the merit that CO2 is the principal GHG forcing >>>> and perhaps the only one with good prospects for quantification of its >>>> long-term changes.*" (page 15) >>>> >>>> However the paper is relevant to the methane issue in several ways. One >>>> argument, which I've heard from Jeff Ridley, is that there is no sign of a >>>> methane excursion at previous interglacials* such as end-Eemian, when it >>>> was >>>> hotter, so we don't need to worry about having an excursion now. Hansen >>>> shows that it was never hotter than it is now (in Holocene) by more than >>>> one >>>> degree. >>>> >>>> Elsewhere Hansen points out that the current rate of global warming is >>>> much higher than it has been for millions of years. Andrew Lockley >>>> suggests >>>> it's higher than even it was at the PETM some 55.8 million years ago, when >>>> temperatures rose about 6 C [3]. That rate of change is important, because >>>> of methane's short lifetime. The increasing speed of change implied by >>>> Hansen's climate sensitivity is thus relevant to methane. >>>> >>>> A further way that the paper is relevant to methane is because of >>>> climate sensitivity to radiative forcing. The paper suggests various >>>> alternative values that could be taken - see [1] table 1. If we get over >>>> 2 >>>> W/m-2 from methane, then that certainly takes us over the danger line of 2 >>>> degrees global warming, using his argument. >>>> >>>> Cheers, >>>> >>>> John >>>> >>>> * During the past 800,000 years, methane never rose much above 700 ppb >>>> until recently, see [1] figure 2 >>>> >>>> [1] Full paper <http://arxiv.org/ftp/arxiv/papers/1105/1105.0968.pdf> >>>> http://arxiv.org/ftp/arxiv/papers/1105/1105.0968.pdf >>>> >>>> Abstract here: >>>> <http://arxiv.org/abs/1105.0968v3>http://arxiv.org/abs/1105.0968v3 >>>> >>>> [2] <http://www.bbc.co.uk/news/science-environment-13002706> >>>> http://www.bbc.co.uk/news/science-environment-13002706 >>>> >>>> [3] >>>> <http://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Thermal_Maximum> >>>> http://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Thermal_Maximum >>>> >>>> --- >>>> >>>> On Thu, Jul 21, 2011 at 11:07 PM, Emily < <em...@lewis-brown.net> >>>> em...@lewis-brown.net> wrote: >>>> >>>>> Hi, >>>>> >>>>> here is a recent paper from Jim Hansen,including some figures I've read >>>>> before, which stunned me: >>>>> >>>>> "In the early Pliocene global temperature was no more than 1-2°C warmer >>>>> than today, yet sea level was 15-25 meters (50-80 feet) higher." >>>>> >>>>> best wishes, >>>>> >>>>> Emily. >>>>> >>>>> >>>>> *Paleoclimate Implications: Accepted Paper and 'Popular Science'* >>>>> >>>>> >>>>> "Paleoclimate Implications for Human-Made Climate Change" has been >>>>> reviewed, revised in response to the referee's suggestions, and >>>>> accepted >>>>> for publication in "Climate Change at the Eve of the Second Decade of >>>>> the Century: Inferences from Paleoclimate and Regional Aspects: >>>>> Proceedings of Milutin Milankovitch 130th Anniversary Symposium" (Eds. >>>>> A. Berger, F. Mesinger and D Šijački), Springer. >>>>> >>>>> This final version has also been published in arXiv:1105.0968v3 >>>>> [physics.ao-ph] >>>>> <<http://columbia.us1.list-manage.com/track/click?u=0ebaeb14fdbf5dc65289113c1&id=fbefcc8464&e=60a7483168> >>>>> http://columbia.us1.list-manage.com/track/click?u=0ebaeb14fdbf5dc65289113c1&id=fbefcc8464&e=60a7483168 >>>>> > >>>>> >>>>> A__'popular science' summary >>>>> <<http://columbia.us1.list-manage.com/track/click?u=0ebaeb14fdbf5dc65289113c1&id=d3b93e0894&e=60a7483168> >>>>> http://columbia.us1.list-manage.com/track/click?u=0ebaeb14fdbf5dc65289113c1&id=d3b93e0894&e=60a7483168 >>>>> > >>>>> of the paper, intended for lay audience, is available. >>>>> >>>>> Thanks especially to reviewer Dana Royer for helpful comments, >>>>> foundations and NASA program managers for research support, and a >>>>> number >>>>> of people for comments on an early draft of the paper, as delineated in >>>>> the acknowledgements. >>>>> >>>>> Jim Hansen >>>>> >>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "geoengineering" group. >>>>> To post to this group, send email to <geoengineering@googlegroups.com> >>>>> geoengineering@googlegroups.com. >>>>> To unsubscribe from this group, send email to >>>>> <geoengineering%2bunsubscr...@googlegroups.com> >>>>> geoengineering+unsubscr...@googlegroups.com. >>>>> For more options, visit this group at >>>>> <http://groups.google.com/group/geoengineering?hl=en> >>>>> http://groups.google.com/group/geoengineering?hl=en. >>>>> >>>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "geoengineering" group. >>>> To post to this group, send email to <geoengineering@googlegroups.com> >>>> geoengineering@googlegroups.com. >>>> To unsubscribe from this group, send email to >>>> <geoengineering%2bunsubscr...@googlegroups.com> >>>> geoengineering+unsubscr...@googlegroups.com. >>>> For more options, visit this group at >>>> <http://groups.google.com/group/geoengineering?hl=en> >>>> http://groups.google.com/group/geoengineering?hl=en. >>>> >>>> >>> >> > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. 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