I haven't seen any chemtrail believers talking about this yet - usually they are all over any actual geo-enginering science like a rash as soon as anything is published - reported in the BBC today :
As per most research the conclusions are pretty much that you don't want to be doing geo-engineering bacuase hte results are a bit unpredictable and might last a lot longer than you want:
Prof Ken Caldeira, of Stanford University, presented research at a major conference on the climate risks and impacts of geoengineering.
These techniques have been hailed by some as a quick fix for climate change.
But the impacts of geoengineering on oceans, the water cycle and land environments are hotly debated.
They have been discussed at a meeting this week of 12,000 scientists in Vienna.
Researchers are familiar with the global cooling effects of volcanic eruptions, seen both historically and even back into the deep past of the rock record.
With this in mind, some here at the European Geosciences Union General Assembly have been discussing the possible worldwide consequences of pumping sulphate aerosols into the stratosphere to attempt to reflect sunlight back into space and cool the planet.
"Deploying solar radiation management methods would lead to a completely new climate state with enhanced greenhouse effect and reduced solar radiation," said Korhonen, adding: "There are great uncertainties, related especially to the regional climate impacts of solar radiation management."
Commenting on the results, Helene Muri, of the University of Oslo, said: "These modelling experiments have highlighted the new risks associated with solar radiation management. The safest option is, of course, to reduce greenhouse gas emissions and aim for a more sustainable way of living and managing the planet."
It is not at all obvious what the other consequences of global geoengineering approaches might be. For example, Patrick Applegate from Pennsylvania State University, reported that solar radiation management may yet fail to prevent sea-level rise from melting ice sheets, which respond on much longer time scales than the temperature effects of solar shielding.