Comment: I suppose it would be the

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I suppose it would be the

I suppose it would be the correct term if it was actually being done:

"The ability of stratospheric sulfate aerosols to create a global dimming effect has made them a possible candidate for use in geoengineering projects[1] to limit the effect and impact of climate change due to rising levels of greenhouse gases.[2] Delivery of precursor sulfide gases such as sulfuric acid,[3] hydrogen sulfide (H2S) or sulfur dioxide (SO2) by artillery, aircraft[4] and balloons has been proposed.[5]"

...and...

"Various techniques have been proposed for delivering the aerosol precursor gases (H2S and SO2).[2] The required altitude to enter the stratosphere is the height of the tropopause, which varies from 11 km (6.8 miles/36,000 feet) at the poles to 17 km (11 miles/58,000 feet) at the equator.
Aircraft such as the F15-C variant of the F-15 Eagle have the necessary flight ceiling, but limited payload. Military tanker aircraft such as the KC-135 Stratotanker and KC-10 Extender also have the necessary ceiling and have greater payload.[4]
Modified Artillery might have the necessary capability,[39] but requires a polluting and expensive gunpowder charge to loft the payload.
High-altitude balloons can be used to lift precursor gases, in tanks, bladders or in the balloons' envelope. Balloons can also be used to lift pipes and hoses, but no moored balloon has ever been deployed to the necessary altitude."

http://en.wikipedia.org/wiki/Stratospheric_sulfate_aerosols_(geoengineering)

And with regard to "geoengineering":

"To date, no large-scale geoengineering projects have been acknowledged publicly, excepting one conducted outside the scientific mainstream by Russ George. Almost all research has consisted of computer modelling or laboratory tests, and attempts to move to real-world experimentation has proved controversial. Some limited tree planting[10] and cool roof[11] projects are already underway. Ocean iron fertilization has been given small-scale research trials.[12] Field research into sulfur aerosols has also started.[13]"

http://en.wikipedia.org/wiki/Geoengineering

"SAG" is not currently being performed by anyone.