Actually the reverse is likely true, but in a good way. As particles rain out, they act as CCN for Cirrus, which forms in cool, clear, saturated air. This causes nucleation, but the particles are rare due to the sparse fluxes (Nc). As the air is saturated, the droplets grow large and rain out. In dirty air, this doesn't work.
This is either a useful side effect, or the basis of Cirrus stripping technology, depending on how you look at it. Off thread, and in response to the post this AM, It's worth considering the injection height for trop sulfur. The lower the injection, the swifter the deposition. This can be dry particulate deposition, or rained out by dissolution in precip. Any trop intervention would likely be at height, eg from tall stacks or aircraft. A On Mar 21, 2012 11:59 AM, "Stephen Salter" <[email protected]> wrote: > Ken > > But if sulphate aerosols spread to lower levels would they not act as > cloud condensation nuclei and so form a blanket of drop large enought to > reflect the long waves? > > Stephen > > Ken Caldeira wrote: > >> If we are talking about Latham's proposal, there would be no reason to >> make clouds in winter. >> If stratospheric sulfate aerosols in the right size range they should be >> too small to have a big impact on outgoing long wave. >> So, seems likely to be a non-issue. >> Ken Caldeira >> [email protected].**edu <[email protected]> >> +1 650 704 7212 >> http://dge.stanford.edu/labs/**caldeiralab<http://dge.stanford.edu/labs/caldeiralab> >> >> Sent from a limited-typing keyboard >> >> On Mar 20, 2012, at 21:55, Michael Hayes <[email protected]> wrote: >> >> >> >>> Folks, >>> As the Arctic situation is the weakest of the weak links in our >>> environment and Stratospheric Particle Injection is a front runner of SRM >>> methods, I believe this is a profoundly important issue. Will a cloud of >>> SRM particles mimic a Winter Time Polar Stratospheric Cloud's ability to >>> trap IR energy? >>> Andrew has blocked my previous efforts to raise this question and I ask >>> that he simply stop censoring this group. >>> Michael >>> -- >>> Michael Hayes >>> 360-708-4976 >>> http://www.voglerlake.com >>> >>> >> >> >> > > -- > The University of Edinburgh is a charitable body, registered in > Scotland, with registration number SC005336. > > -- > 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<[email protected]> > . > To unsubscribe from this group, send email to geoengineering+unsubscribe@* > *googlegroups.com <geoengineering%[email protected]>. > 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 [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.
