Renaud et.al., I'm 100% behind any effort to stop *any *particulates from being released. However, the current levels of BC/S seems to be keeping the atmospheric moisture levels (i.e. global tempurature) artificially low (up to 10% per S. Solomon <http://eaps-www.mit.edu/people/solos>) through the BC/S wetting process. At this time, I can not find the study in which she described this phenomena, yet I'm sure I can eventually find it if you need.
Has the proposed particulate cleaning/trans-boundary injection method considered the overall climate temperature implications of reducing the BC/S wetting (i.e. moisture reduction/global temperature) factor? Best regards, Michael On Friday, August 1, 2014 5:53:56 AM UTC-7, Renaud de_Richter wrote: > > Currently, anthropogenic tropospheric aerosols present both Dr Jekyll and > Mr Hyde faces. > > > > On the one hand, tropospheric aerosols play an important role on climate, > with a net cooling radiative forcing effect. > > On the other hand, tropospheric aerosols affect terrestrial ecosystems > and human health and are associated with increased heart, lung and > respiratory diseases, which lead to disablement and numerous premature > human deaths (Shindell et al, 2012). > > > > Consequently, reducing anthropogenic tropospheric aerosols emissions, on > the one hand will lead to a positive forcing (warming) at local and > regional scale, and on the other hand will save numerous lives and > significantly reduce health costs. > > > > *What is proposed is to investigate means whereby the cooling effect of > current emissions is kept unchanged and their deleterious effects are > reduced,* using only modifications of existing industrial aerosols > emitters. Key advantages of such investigations are that they avoid most of > the roadblocks associated with SRM. > So, what is proposed is a Win-Win research program that will at the same > time allow indirect geoengineering research, and reduce tropospheric > pollution. > > *(Important remark: it is not proposed to perform CCS, or CDR).* > > > > This is so, because the current anthropogenic tropospheric sulphate > aerosol emissions are estimated to be *almost two orders of magnitude > larger* than requested by Stratospheric Particle Injection geoengineering > schemes to offset the effects of a 2 X CO2 (carbon dioxide concentration > doubling in the atmosphere). > > Thus the strategy to reduce current sulphate *tropos*pheric emissions and > at the same time to keep their current cooling effects will be like > performing indirect climate engineering without the need to artificially > inject > sulphates in the *strato*sphere. > > > > Now, the radiative forcing due to sulphate aerosols is estimated to be > −0.4 W/m2 with a range of −0.2 to −0.8 W/m2. > On a global average basis, the sum of direct and indirect radiative > forcing at the top of atmosphere by anthropogenic aerosols is estimated to > be −1.2 W/m2 [−2.4 to −0.6 W/m2] (*cooling*) over the period of 1750 - > 2000. This is significant when compared to the positive (*warming*) > forcing of +2.63 [±0.26] W/m2 by anthropogenic long-lived greenhouse > gases over the same period [Forster et al., 2007]. > In heavily polluted regions, aerosol cooling overwhelms greenhouse warming > [Ramanathan et al., 2001; Li et al., 2010]. > > > > The tropospheric aerosol lifetimes are approximately 1 to 2 weeks, which > is quite shorter. Therefore, these current human made aerosols have an > uneven distribution, both horizontally and vertically, and are more > concentrated near their source regions over continents and in the boundary > layer. > > *Emission reductions of aerosols in the troposphere will lead to a > positive forcing (warming), unless the sulphates lifetimes are increased > and their horizontal and vertical distribution are improved. **Whilst the > particulates are removed, some part of the sulphates can be lofted higher > to where they can act as a solar-reflective shield to cool larger regions.* > > > > To do so, what is proposed is to model the effects of a theoretical > fivefold aerosols emission reduction (80% removal of sulphates, NOx, and > > 95% removal of soot, black carbon, ash…) by adding filters or electrostatic > precipitators to the flue stack of a majority of fossil fuel fired power > plants, for adequate particulate filtering and scrubbing, and *at the > same time increasing the height release of sulphates for a reduced number > of other power plant stacks in order to allow these (20% SOx) emissions to > over pass the boundary layer and stay longer in the atmosphere*. > > > > This can be performed by the use of taller chimneys allowing the flue > gases to pass the boundary layer, so that the impact of a regional emission > reduction is not confined to the region itself, by allows intercontinental > transport (long-range transport) of these sulphates *produced by existing > anthropogenic aerosols*. > Several other possibilities exist to increase the height release and > dilution of gas emissions from flue stacks. > > > > This strategy was proposed in page 818-819 of an *open access article* > http://www.sciencedirect.com/science/article/pii/S1364032113008460 > Fighting global warming by climate engineering. > > > > *Two figures are attached to summarize this research proposal* > > > Public perception of SRM climate engineering is often presented as Ulysses > choices between the perils of Scylla and Charybdis, despite the very good > cooling potential to mitigate global warming, and the high effectiveness > and accessibility of geoengineering schemes consisting of the > stratospheric injection of sulphate aerosols. > > The Win-Win strategy proposed here may change this perception at the same > time as helping to advance CE research... > > > Renaud de_Richter, PhD > > http://www.solar-tower.org.uk/ > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. 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