Alvia Let me emphasize John's point about keeping her steady as she goes.
I think that any dimethyl sulphide in sea water will get through the spray system and go up along with the salt residues to do its stuff with clouds. The size range should be ideal for transport by turbulence so that a higher fraction will be lofted than the water from breaking waves, much of which falls back rapidly. But given that figure 5 of the wave sink paper shows that such a large fraction of the oceans is empty of phytoplankton, will there by any dimethyl sulphide to spray? This engineer needs help from marine biologists. Stephen Emeritus Professor of Engineering Design School of Engineering and Electronics University of Edinburgh Mayfield Road Edinburgh EH9 3JL Scotland tel +44 131 650 5704 fax +44 131 650 5702 Mobile 07795 203 195 s.sal...@ed.ac.uk http://www.see.ed.ac.uk/~shs John Latham wrote: > Hello All, > > I think this is an interesting and seemingly authoritative > observational study, with some so far limited modelling support.It > will be valuable to ascertain whether the findings - at the moment > limited to low clouds over the NE Pacific - are reproduced globally, > and confirmed in other models.. > > If we assume that they are, it is pertinent to ask what the > implications are vis-a-vis solar radiation management geoengineering > schemes. If, as with our cloud albedo enhancement scheme, the idea is > - as far as possible - to stabilise the Earth's average surface > temperature, probably at current values, by varying the cooling in > concert with the warming, the cloud cover / temperature positive > feedback relationship would not come in to play. If, for any reason, > we wished to produce an overall smallish cooling - for example to > cool ocean waters in order to try to reduce the energy of hurricanes > that subsequently form in those regions - the positive feedback should > reinforce the geo-engineered cooling. > > So Steve should not sigh too deeply. > > All Best, John. > > > > > Quoting Alvia Gaskill <agask...@nc.rr.com>: > > > > > From reading the paper, it seems that the reason for less clouds > with higher > > SST due to CO2 forcing is due in part to a much quieter ocean, i.e., > less > > wind and less waves. The way that CCN from DMS from marine bacteria and > > salt particles get into the atmosphere is in part due to breaking of > waves. > > If you heat the water gently, without disturbing it, you may get > more water > > vapor into the atmosphere, but without the accompanying CCN. Better put > > some big assed propellers on those cloud boats, Salter as your > mission may > > have just been expanded. > > > > > > ----- Original Message ----- > > From: "Tom Wigley" <wig...@ucar.edu> > > To: <s.sal...@ed.ac.uk> > > Cc: "Climate Intervention" <climateintervent...@googlegroups.com>; > > "geoengineering" <geoengineering@googlegroups.com> > > Sent: Sunday, July 26, 2009 6:07 AM > > Subject: [geo] Re: [clim] Yet another positive feedback > > > > > >> > >> The real issue is the total magnitude of feedbacks, as > >> characterized by (e.g.) the equilibrium global-mean warming > >> for 2xCO2 (DT2x). > >> > >> The breakdown of the feedbacks is not directly relevant to > >> this -- although it is of interest in model validation. > >> > >> This paper tells us nothing about DT2x or its uncertainty. > >> My comment -- so what. > >> > >> Tom. > >> > >> +++++++++++++++++ > >> > >> Stephen Salter wrote: > >>> Hi All > >>> > >>> Science July 24 from > >>> http://www.sciencemag.org/cgi/reprint/325/5939/460.pdf has a > >>> something about a positive feedback between sea temperature and cloud > >>> cover. I had thought that warmer seas would increase evaporation > and so > >>> cloud cover but drying them out seems to win. > >>> > >>> Sigh. > >>> > >>> Stephen > >>> > >> > >> > >> > >> > > > > > > > > > > > > > -- > John Latham > > lat...@ucar.edu & john.latha...@manchester.ac.uk > > Tel. 303-444-2429 (H) & 303-497-8182 (W) > -- 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 To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en -~----------~----~----~----~------~----~------~--~---
