Of course the sulfates have a short life. But, for small injections, the heat budget would net out. Of course, you could inject 1pc of the total every year.
I dealt with this in more depth in a paper, but I never did the calculations. On Fri, 10 Apr 2020, 17:43 Michael MacCracken, <mmacc...@comcast.net> wrote: > Hi Alan--Is there a comparative and comprehensive assessment that > indicates that the risks from injecting sulfates into the stratosphere that > you raise are greater than the alleviated risks from global warming that is > cancelled out, and how this evaluation changes with amounts of warming and > cooling and how the evaluation might vary as one considers near-term to > long-term aspects (and including related aspects like sea level rise and > ocean acidification impacts)? > > Mike > On 4/10/20 12:31 PM, Alan Robock ☮ wrote: > > Dear Andrew, > > I'm not sure I understand. How do you propose to put the sulfate into the > stratosphere? And will you be personally responsible for your share of the > risks associated with the impacts? > > Alan > > Alan Robock, Distinguished Professor > Associate Editor, Reviews of Geophysics > Department of Environmental Sciences Phone: +1-848-932-5751 > Rutgers University E-mail: rob...@envsci.rutgers.edu > 14 College Farm Road http://people.envsci.rutgers.edu/robock > New Brunswick, NJ 08901-8551 USA ☮ http://twitter.com/AlanRobock > > On 4/10/2020 12:13 PM, Andrew Lockley wrote: > > I've just run some numbers on what my 'personal sulfate budget' might be. > By the calculations below, if a typical person put 10kg sulphate in the > stratosphere for every year of their life, they'd net out their entire RF > carbon footprint for a century. > > Obviously, this has a whole pile of caveats and flaws, but is it vaguely > right? Is it a useful concept? > > Here's the obvious caveats: > Need temporally and spatially even distribution > Doesn't work once CO2 forcing very high > Assumes full offset of future emissions, nil of historic > Termination shock, ocean acidification, Etc. > > Andrew > > > -0.25 (W m-2)/ (Tg-S yr-1) from Wake > 1.5 trillion tonnes CO2 historic 2017 > https://ourworldindata.org/co2-and-other-greenhouse-gas-emissions#cumulative-co2-emissions > 1.6 w/m2 Current RF 2010 (bit out of date) > Approx 1 Tt/W (calculated) > 10t/capita/Yr CO2 only (UK), nearly 14 Co2e > https://www.carbonindependent.org/23.html > To Offset everything all historic CO2 6Tg/yr > 1 persons annual emissions is 1.5 x 100 billionths of the total ever > emitted > > Personal sulfate injection is therefore 6Tg x 1.5 / 100bn = about 100g > per year for 1y emissions only > If each person wants to offset a year's emissions for a century (negating > 100y GWP), it's 100x More — ie 10kg per year > -- > 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 view this discussion on the web visit > https://groups.google.com/d/msgid/geoengineering/CAJ3C-05HKVDJ8aYPr3dxk_N2Zecnd9kwz3%3DUo8MECqKxe1mt6g%40mail.gmail.com > <https://groups.google.com/d/msgid/geoengineering/CAJ3C-05HKVDJ8aYPr3dxk_N2Zecnd9kwz3%3DUo8MECqKxe1mt6g%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > > > -- > 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 view this discussion on the web visit > https://groups.google.com/d/msgid/geoengineering/c04f414e-4da2-7a30-3890-2401ecc95727%40envsci.rutgers.edu > <https://groups.google.com/d/msgid/geoengineering/c04f414e-4da2-7a30-3890-2401ecc95727%40envsci.rutgers.edu?utm_medium=email&utm_source=footer> > . > > -- > 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 view this discussion on the web visit > https://groups.google.com/d/msgid/geoengineering/706e49a6-559c-3c04-b3bc-7e454a985ec5%40comcast.net > <https://groups.google.com/d/msgid/geoengineering/706e49a6-559c-3c04-b3bc-7e454a985ec5%40comcast.net?utm_medium=email&utm_source=footer> > . > -- 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 view this discussion on the web visit https://groups.google.com/d/msgid/geoengineering/CAJ3C-07uA5SXMFQZJv1%2BHvKfkm%3DQpgTkS71jnCuwc3_Qkx5RKg%40mail.gmail.com.
