Yes, you could produce even more new particles yourself which would inhibit new particle production from someone else's emissions, but presumably the total particle count would be higher at the end of all of this than if you did not intervene.
Would it be possible to act on someone else's particle production in a way that would lower overall particles counts? On Sun, Oct 17, 2010 at 1:50 PM, Oliver Wingenter < [email protected]> wrote: > Dear Josh, > > If the concentration of background particle were large enough, a few > hundred particle per cm3, then this would inhibit new particle production. > At least this is case in the marine boundary layer. I understand that > stratospheric microphysical models are having trouble making new particles. > However, adding NH3 would allow ternary nucleation tens of thousands of > times faster than sulfuric acid and water alone as is seen in the free > troposphere. > > In terms of a volcanic eruptions like Pinatubo, I wonder how much ash made > it to the stratosphere and provided nucleation sites? > > Sincerely, > > Oliver Wingenter > > > On 10/17/2010 12:29 PM, Ken Caldeira wrote: > > Multiple, independent injections would *decrease *the likelihood of > coagulation relative to injecting it all in one place. > > Of course, there is potential for coordinated injections to decrease > coagulation (aggregation) relative to uncoordinated injections. > > There is no evidence that I know of that one injection could "cancel out" > the effects of another injection. It seems that the main case is that the > climate effect of A+B would be less than the climate effects of A plus the > climate effects of B. > > It is an interesting research question to understand whether there are > countermeasures that would decrease the effectiveness of injection by > injecting something upwind from an injection site that would promote > aggregation of the injected material. > > ___________________________________________________ > Ken Caldeira > > Carnegie Institution Dept of Global Ecology > 260 Panama Street, Stanford, CA 94305 USA > +1 650 704 7212 [email protected] > http://dge.stanford.edu/labs/caldeiralab @kencaldeira > > > On Sun, Oct 17, 2010 at 10:43 AM, Josh Horton > <[email protected]>wrote: > >> Hi everyone, >> >> I am finalizing a chapter on geoengineering policy for publication and >> would greatly appreciate informed feedback on the following paragraph: >> >> "The aerosol most commonly suggested for stratospheric injection is >> sulfuric acid. Plans call for delivering sulfate aerosols by >> dispersing gas-phase precursor materials. Precursor oxidation and >> aerosol formation involve complex processes with the potential to >> reduce the effectiveness of stratospheric insertion. For instance, >> coagulation could lead to excessively large sulfuric acid particles >> that sediment out of the stratosphere, neutralizing the effect of the >> initial dispersion. Multiple, independent injections would increase >> the likelihood of such unintended consequences. Unsynchronized >> staging, scheduling, and delivery of sulfate aerosol injections would >> magnify the potential for perverse particulate interactions, and might >> jeopardize the success of geoengineering deployment. Lack of policy >> coordination may result in separate injection schemes that effectively >> cancel each other out." >> >> For those with scientific/technical backgrounds, is this a sound >> argument? Is the basic science correct? I am outside my comfort zone >> with this and want to be sure I don't miss the mark. Thanks to anyone >> who can offer insight. >> >> Josh Horton >> [email protected] >> http://geoengineeringpolitics.blogspot.com/ >> >> -- >> 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]<geoengineering%[email protected]> >> . >> For more options, visit this group at >> 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 [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=en. > > -- 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=en.
