John -  Sorry I haven't responded earlier.  I think I can speak for 
quite a few others in the "Biochar tribe" when I offer below some 
comments on what you have written.  I do wholeheartedly agree with the 
thrust that we are not doing enough today.

John Nissen wrote:
>
> Hi Jim,
>
> I want to follow up on your email of 15th November.
>
> So far, nobody has challenged the logic of my argument.  So we all 
> seem to be in agreement!  It's not what we'd like to believe, but the 
> conclusion is clear.
>
> Why are most academics among us so reticent?  Jim Hansen has noticed 
> this too.  When the outlook is bad, nobody wants to be the messenger.  
> So why don't we have a manifesto, which people can sign up to?  When I 
> originally suggested this, Alan Robock flatly rejected the idea that 
> we had any agreement in the group.
>
> So I put out the challenge again.  Does anybody disagree with my 
> simple argument for SRM geoengineering?  I'll repeat it:
>
> ---
> > 1. Global warming is driven largely by atmospheric CO2 according to the
> > concentration above its pre-industrial level.   *[RWL1: Although "largely" 
> > is correct, I think you opening statement should include all GHGs (and land 
> > disturbances - mainly because they all (??) have shorter lifetimes than 
> > CO2, and are probably mostly cheaper.]*
>   
> > 2. After emissions are stopped it could take millenia for the
> > concentration to fall back to that level, because the effective lifetime
> > of some of that excess CO2 is many thousands of years.  *[RWL2:   I'd 
> > change "could" to "will", and drop "effective" and "some of".*
> >
> > Therefore:
> > 3.  Drastic emissions reduction, even to zero overnight, cannot and will
> > not stop the Arctic continuing to warm for decades.    *[RWL3:  I'd 
> > rephrase to read:  "Even total elimination of all GHG emissions will not 
> > stop the Earth, and especially the polar regions, from continuing to warm 
> > for decades."  (Emphasizing all causes of warming again - as in #1, and 
> > trying to show the bigger impacts at the poles (both).
> >*
> > Therefore:
> > 4. The Arctic sea ice will continue to retreat, accelerating the warming
> > due to the albedo effect.  *[RWL4:  Probably OK, but I worry as much about 
> > thinning (melting from below and above both due to temperature changes - 
> > not just albedo.  Greenland and the Antarctic ice are disappearing for more 
> > than albedo reasons.]*
> >
> > Therefore:
> > 5.  The permafrost will continue to thaw releasing increasing quantities
> > of methane, a potent greenhouse gas, potentially adding many degrees to
> > global warming; and *[RWL5:   I'd replace "potentially adding many degrees 
> > to" to "adding to"]*
> >
> > 6.  The Greenland ice sheet will become increasingly unstable,
> > potentially contributing to an eventual sea level rise of 7 metres.   
> > *[RWL6:  I'd add Antarctica and be less specific on the exact level of sea 
> > rise;  I'd drop "potentially".]*
> >
> > Therefore:
> > 7.  To avoid these two catastrophes, we need to cool the Arctic quickly
> > enough to save the Arctic sea ice.  *[RWL7:  I'd continue talking about 
> > both poles.  Don't think you need the last clause - this whole series is 
> > all about ice.*
> >
> > 8.  Probably the only feasible way to do this is through solar radiation
> > management (SRM) geoengineering.   *[RWL8:   My main negative reaction is 
> > on this sentence.  "Probably" is weak.   I personally believe***, as a 
> > Biochar supporter,*** that a more sure way to solve all our AGW problems is 
> > to take CO2 out of the atmosphere.  Albedo is hugely important, but I need 
> > to hear more about the exact "SRM" technique you are proposing.  Albedo or 
> > reduced input?   Mirrors or SO2?  Reversible?  Whose ox might get gored?)*
> >
> > 9.  SRM is not to be left as a last resort; it is needed now to cool the 
> > Arctic.  *[RWL: With some changes that included CO2 removal and was more 
> > specific on the exact SRM technique being proposed, I might be able to 
> > sign.   I think I may be demonstrating why Alan Robock said what he did. 
> > Hope you see something useful above.     Ron*
> ---
>
> Cheers,
>
> John
>
> ---    <snip rest>

--

You received this message because you are subscribed to the Google Groups 
"geoengineering" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to 
[email protected].
For more options, visit this group at 
http://groups.google.com/group/geoengineering?hl=.


Reply via email to