Isn't all of this excessive political correctness over potential geoengineering experiments likely to make it more difficult to do experiments aimed at better understand aerosol forcing?
Can somebody who believes that a certain class of experiments requires exceptional treatment by virtue of being a 'climate engineering experiment' or 'geoengineering experiment' please provide me with an operational definition that would allow a potential regulator to unambiguously determine whether a proposed experiment aimed at understanding climate consequences of aerosols does or does not constitute a 'climate engineering experiment' or 'geoengineering experiment' ? On Fri, Aug 22, 2014 at 11:41 AM, Andrew Lockley <[email protected]> wrote: > Poster's note : those pesky clouds are still proving a source of much > debate. Dealing with changes in forcings as aerosols are cleaned out in > coming decades will be a major challenge. This could be the tipping point > for SRM adoption. > > > http://onlinelibrary.wiley.com/doi/10.1002/2014JD021670/abstract?utm_content=buffer8dee2&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer > > Keywords: > > aerosol;satellite-based estimate;direct forcing;indirect forcing > > Large uncertainties exist in estimations of aerosol direct radiative > forcing (DRF) and indirect radiative forcing (IRF), and the values derived > from global modeling differ substantially with satellite-based > calculations. Following the approach of Quaas et al. (2008; hereafter named > Quaas2008), we reassess satellite-based clear- and cloudy-sky radiative > forcings and their seasonal variations by employing updated satellite > products from 2004 to 2011 in combination with the anthropogenic aerosol > optical depth (AOD) fraction obtained from model simulations using the > GEOS-Chem-APM. Our derived annual mean aerosol clear-sky forcing (-0.59 > Wm-2) is lower while the cloudy-sky forcing (-0.34 Wm-2) higher than the > corresponding results (-0.9 Wm-2 and -0.2 Wm-2, respectively) reported in > Quaas2008. Our study indicates that the derived forcings are sensitive to > the anthropogenic AOD fraction and its spatial distribution but insensitive > to the temporal resolution used to obtain the regression coefficients, i.e. > monthly or seasonal-based. The forcing efficiency (i.e. the magnitude per > anthropogenic AOD) for the clear-sky forcing based on this study is 19.9 > Wm-2, which is about 5% smaller than Quaas2008's value of 21.1 Wm-2. In > contrast, the efficiency for the cloudy-sky forcing of this study (11 Wm-2) > is more than a factor of two larger than Quaas2008's value of 4.7 Wm-2. > Uncertainties tests indicate that anthropogenic fraction of AOD strongly > affect the computed forcings while using aerosol index (AI) instead of AOD > from satellite data as aerosol proxy does not appear to cause any > significant differences in regression slopes and derived forcings. > > -- > 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/d/optout. > -- 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/d/optout.
