A fleet of high-altitude balloons could be used to scatter the sulphur high overhead, or it could even be fired into the atmosphere using heavy artillery shells, said Professor Crutzen, a researcher at the Max Planck Institute for Chemistry in Germany.
His plan is modelled partly on the Mount Pinatubo volcanic eruption in 1991, when thousands of tons of sulphur were ejected into the atmosphere causing global temperatures to fall. Pinatubo generated sulphate aerosols in the atmosphere which cooled the Earth by 0.5C on average in the following year. The sulphate particles did this by acting like tiny mirrors, preventing a portion of incoming sunlight from reaching the ground.Some scientists aren't too happy with the plan, lest it encourage people to keep driving Hummers and leaving their VCRs on standby, secure in the knowledge that they can always spray some sulphur into the upper atmosphere if things get too bad.
This is only one of several proposed "geo-engineering" ideas to remedy the symptoms of climate change by technological means; others involve boosting the growth of CO2-swallowing plankton and floating white plastic islands on oceans to replace all the highly reflective sea ice that has melted. (Speaking of sending the wrong message, one can't top the last one; I wonder how many people will use it as an excuse for throwing plastic bags into drains.)