Hi Andrew--Ah yes, reality. I was not being quite so serious about this as your comments suggest I was thinking, but this pumice is sort of a natural analog for having anything, hopefully better designed, floating on the ocean as a way to increase reflectivity.
Aside from the issues you raise, another problem with such an approach, illustrated by the waste from the Japanese tsunami, is that the debris tends to concentrate in the eddies where water is descending, so actually, having any such material have a finite lifetime would be useful so it would eventually sink. As Seitz has suggested, of course, the optimal material (from a contamination sense) would be air bubbles--it is just that their lifetime would likely be too short to be practical (but still to be determined). In any case, quite an interesting phenomenon. Mike On 8/8/12 10:02 AM, "Andrew Lockley" <[email protected]> wrote: > Mike > > It occurs to me that there a few issues with this idea: > > Pumice is intermittently produced in the environment, so the presence > of a pumice layer on the ocean surface can be considered with a > source/reservoir/sink model. The sinks would seem to be dominant, as > there is no extant, visible layer. Pumice is less dense than water > purely because of gaseous inclusions in the rock. Over time, it would > appear reasonable that there is a loss of this gas by dissolution or > ebullition into the water column. Pumice would then join the general > marine snow, and should be detectable in the sediment layer. An > alternative model for the fate of pumice is mechanical destruction of > the particles by collision (wave action) or chemical dissolution of > the surrounding rock structure. As these processes progress, it is > likely that the albedo of the material would appreciably change, > potentially leading to a near neutral albedo effect. > > Furthermore, the radius of the pumice particles is likely non-optimal > for geoengineering use. The micron-sized particles proposed for SRM > have MT/yr fluxes. Larger particle sizes would require larger fluxes. > These substantial fluxes could negatively affect the marine > environment. > > Best, > > A > > On 8 August 2012 14:25, Mike MacCracken <[email protected]> wrote: >> Now here is an idea we have not considered‹covering all or part of the ocean >> in pumice. >> >> Mike MacCracken >> >> >> From: Robert Drew [mailto:[email protected]] >> Sent: Wednesday, August 08, 2012 6:31 AM >> To: Robert Drew >> Subject: FW: AMAZING SIGHT IN THE SOUTH PACIFIC >> >> You have to see this! From a sailing mate. >> >> >> >> >> >> AMAZING SIGHT IN THE SOUTH PACIFIC >> >> The yacht 'Maiken' was traveling in the south Pacific when the crew came >> across a weird sight. >> It was sand in the water, and the sand was floating ON TOP of the waves... >> Look at these photos and try to imagine the feeling, the thrill of >> experiencing this phenomenon close-up. >> >> >> >> >> >> >> This is not a beach, it is volcanic stones floating on the water! >> >> >> >> >> >> >> >> >> >> The trail left by the yacht... through the sand >> And then this was spotted... just behind them... ash and steam rising from >> the ocean... >> >> >> And, while they were watching... >> >> >> >> >> A plume of black ash... >> >> >> >> >> >> >> >> >> >> >> >> >> A brand new island formed... >> >> >> >> >> >> >> Awesome! >> Can you imagine the thrill of being the first & only people to see a new >> island being created... where there was nothing before? >> >> Then, can you imagine thinking -- >> "Gee if I been a few minutes later, I might have gone up in that explosion >> of >> black volcanic ash when the eruption occurred" >> >> -- Now there's a scary thought!!! >> >> >> >> >> -- >> 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.
