| Yes, this has been studied quite a bit (but not "extensively"). I am (guardedly) a fan of managing the earth's albedo, but not on a global scale and especially not with a toxic compound like SO2. Some of the most important issues: * It's not just SO2, but soot and other particulates that reflect sunlight, in particular IR. * SO2 (and soot etc, for that matter) have other side effects; its not that they were eliminated for no reason. And the point of any ecological activity (not just climate intervention) is to make the environment more supportive to human life and ativity. Stratospheric SO2 advocates tend to dismiss these issues. * solar radiation adjustment has other consequences (on agriculture, for example).
In the case of SO2 the frequencies reflected by SO2 are not all ones we want to do without -- we need some UV to get through. * Stratospheric SO2 injection (AKA "SAI") is hard to switch off, so if we are unhappy with the results (widespread reduction in agriculture, if that's what happens) we would be waiting years, possibly decades, to get things back on track. Solar radiation can also be managed at a more local level in the troposphere through marine cloud brightening for example, and can be done with more benign chemicals than SO2 (e.g. water), and can be switched on and off quite rapidly (days). It will use more energy and activity, but also provide greater control (in some locations on the water you may not want increased shade because of microscopic marine life). Note I am working on removal of ambient greenhouse gas (CH4) and so am quite sensitive to the safety and consequences of intervention. |