Hi Andrew: Agreed. Speculating a bit, if, as Jennifer Francis hypothesis is right that the jet stream has become wavier as the equator-pole gradient has been reduced, then one would expect for the jet to be pushed back toward the more zonal flow of the past, but that certainly needs to be a question that is researched. Do remember that without doing anything, global warming will continue to go on essentially unabated.
Mike On 9/3/13 4:23 PM, "Andrew Lockley" <[email protected]> wrote: > Speaking as a periodically soaked/parched and frozen/boiled brit, I think > that the effect of polar only SRM on the jet stream would need to be > thoroughly investigated before anyone seriously proposed it. > > A > > On Sep 3, 2013 9:17 PM, "Mike MacCracken" <[email protected]> wrote: >> Hi Bill‹That is a good question to look closely at. I would suggest, without >> having done the studies, so doing so speculatively, that in that the complex >> pattern of geography, land-sea, etc. currently lead to energy being added now >> to the atmosphere in an uneven way, and so I am not convinced having some >> moderate unevenness would be a problem, etc. Yes, in detail, the weather >> would be affected, but the question is whether the statistics of the weather >> (i.e., the climate) is altered. But, indeed, research is needed on this. >> >> Mike >> >> >> >> >> On 9/3/13 2:51 PM, "William H. Calvin" <[email protected] >> <http://[email protected]> > wrote: >> >>> Re the more detailed model: Both high haze and MCB have a problem, that of >>> uneven application and its probable consequences. >>> >>> Big perturbations in seasonal delivery of moisture to a region result in >>> drought and/or deluge. Indeed, one states' drought may be another state's >>> deluge, simply because of a detour in the precip pipeline. What can cause a >>> detour? >>> >>> The current example comes from the land warming twice as fast as the ocean >>> surface, the excess high pressure systems over land forcing a rearrangement >>> in flow patterns. Uneven external forcing is another way, cooling one region >>> to create denser air while not doing the same to its neighbors. Winds >>> rearrange. >>> >>> Thus my concern about uneven application of shadows. But shadows have >>> penumbrias that vary with the length of the shadow. In our eyes, shadows >>> caused by debris floating around can be seen only if the obstruction is >>> close to the retina. If the debris is halfway back to the lens, its shadow >>> will be too fuzzy to register. >>> >>> Thus I see uniform sunlight reduction as necessary to avoid additional >>> drought and deluge, and see the most likely way of achieving uniformity to >>> involve sunscreens that are far above the atmosphere. >>> >>> Of course, success in reducing solar input would do nothing for reducing >>> ocean acidification since dimming will not get rid of the growing excess of >>> CO2. Air capture of CO2 is the only thing I know that could back us out of >>> the danger zone for extreme weather and acidification. >>> >>> Cheers, >>> -Bill >>> >>> On Monday, September 2, 2013 7:49:54 AM UTC-7, Mike MacCracken wrote: >>>> A new paper by myself, Ho-Jeong Shin, Ken Caldeira, and George Ban-Weiss >>>> that provides a conceptual look at the notion of polar SRM is available for >>>> free download at http://www.earth-syst-dynam.net/4/301/2013/ >>>> >>>> The results suggest that a much more detailed model evaluation of this >>>> possible approach to limiting the amplified climate change in high >>>> latitudes >>>> is merited. >>>> >>>> Mike MacCracken >>>> >>>> -- 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 [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/groups/opt_out.
